![]() Interleaved converter
专利摘要:
The purpose of the invention is to obtain an interleaved converter having a converter efficiency that can be more improved by efficiently utilizing an inductor even in a low power load and capable of being operated at a higher efficiency. The interleaved converter (50) is constituted by connecting a plurality of switching converter circuits in parallel and comprises: an inter-inductor switch (103a) that selects whether or not to connect inductors (5a, 5b) in series; an input-side switch (101a) that is connected to the connection point between the inductor (5a) and the inter-inductor switch (103a) and selects whether or not to supply power from a rectifier circuit (2) to the side of the inductor (5a); an output-side switch (102a) that is connected to the connection point between the inductor (5b) and the inter-inductor switch (103a) and selects whether or not to supply power from the inductor (5b) to the side of a diode (7b); and a control circuit that controls the inter-inductor switch (103a), the input-side switch (101a), and the output-side switch (102a). 公开号:AU2012368602A1 申请号:U2012368602 申请日:2012-07-13 公开日:2014-08-14 发明作者:Shinichiro URA 申请人:Mitsubishi Electric Corp; IPC主号:H02M3-155
专利说明:
Docket No. PMDA-13240-PCT 1 DESCRIPTION INTERLEAVED CONVERTER 5 Field [0001] The present invention relates to an interleaved converter in which two or more switching converter circuits are connected in parallel. 10 Background [0002] According to a market request for energy saving in these days, there are electrical appliances that continuously operate at extremely low power consumption with respect to the rated power consumption. In electrical 15 appliances including converter circuits, there is a demand for efficient power conversion even during continuous operation at low power consumption. [0003] In particular, in a switching converter in which a semiconductor switch is used, in low power consumption of 20 a load (i.e., a low load), compared with high power consumption of the load (i.e., a high load), the ratio of the power loss of the converter to the input power increases and the converter efficiency is deteriorated. Therefore, various proposals have been made to suppress the 25 converter efficiency deterioration during the low load. [0004] For example, there is proposed a technology for performing control for, when a load requests a relatively low power level, detecting the state of the load, disabling one or more switches among two or more switches according 30 to the detected state to thereby reduce the switching loss and, when additional electric power is required, restoring the one or more already-disabled switches to an operation state to satisfy the power request (e.g., Patent Literature Docket No. PMDA-13240-PCT 2 1). Citation List Patent Literature 5 [0005] Patent Literature 1: Japanese Translation of International Patent Application No. 2003-523156 Summary Technical Problem 10 [0006] In the technology described in Patent Literature 1, an inductor connected to a switch disabled, that is, changed to a stop state during a low load is not energized. Therefore, the inductor does not contribute to efficient power conversion. In such an operation method for stopping 15 a switch in a low-power load, an inductor not energized in the low-power load is not significant. In particular, when an operation time in the low-power load is long, effective utilization of the inductor is requested even in the low power load. However, a literature referring to the 20 effective utilization of the inductor in the low-power load is not laid open to the public. [0007] The present invention has been devised in view of the above and it is an object of the present invention to provide an interleaved converter capable of effectively 25 utilizing inductors even in a low-power load to further improve converter efficiency and enabling more highly efficient operation. Solution to Problem 30 [0008] To solve the above problems and achieve the object, an interleaved converter that is configured by connecting in parallel a plurality of switching converter circuits configured by inductors, switching elements, and Docket No. PMDA-13240-PCT 3 diodes, that rectifies, with a rectifier circuit, an alternating-current voltage supplied from an alternating current power supply, and that switches, with the switching elements, an output voltage of the rectifier circuit via 5 the inductors to perform one or both of power factor improvement and a boosting operation and to supply electric power to a load, the interleaved converter including: an inter-inductor switch that makes it possible to select whether the inductors are connected in series; an input 10 side switch that is connected to a connection point of the inductor and the inter-inductor switch and makes it possible to select whether electric power is supplied from the rectifier circuit to the inductor side; an output side switch that is connected to a connection point of the 15 inductor and the inter-inductor switch and makes it possible to select whether electric power is supplied from the inductor to the diode side; and a control circuit that controls the inter-inductor switch, the input side switch, and the output side switch. 20 Advantageous Effects of Invention [0009] According to the present invention, there is an effect in that it is possible to effectively utilize an inductor even in a low-power load to further improve 25 converter efficiency and enable more highly efficient operation. Brief Description of Drawings [0010] FIG. 1 is a diagram of a configuration example of 30 an interleaved converter according to a first embodiment. FIG. 2 is a diagram of the configuration of first switching converter circuits during a high-load operation mode of the interleaved converter according to the first Docket No. PMDA-13240-PCT 4 embodiment. FIG. 3 is a diagram of current waveforms and PWM signal waveforms for causing switching elements to operate during the high-load operation mode of the interleaved 5 converter according to the first embodiment. FIG. 4 is a diagram of a full-wave rectified voltage waveform, a load voltage waveform, and a supply voltage waveform to a load during the high-load operation mode of the interleaved converter according to the first embodiment. 10 FIG. 5 is a diagram of the configuration of a second switching converter circuit during a low-load operation mode of the interleaved converter according to the first embodiment. FIG. 6 is a diagram of current waveforms and PWM 15 signal waveforms for causing the switching elements to operate during the high-load operation mode of the interleaved converter according to the first embodiment. FIG. 7 is a diagram of a full-wave rectified voltage waveform, a load voltage waveform, and a supply voltage 20 waveform to the load during the low-load operation mode of the interleaved converter according to the first embodiment. FIG. 8 is a diagram for explaining operation mode switching conditions corresponding to the magnitude of the load power in the interleaved converter according to the 25 first embodiment. FIG. 9 is a flowchart explaining an example of operation mode switching control in the interleaved converter according to the first embodiment. FIG. 10 is a diagram of a configuration example of an 30 interleaved converter according to a second embodiment. FIG. 11 is a diagram of the configuration of first switching converter circuits during a high-load operation mode of the interleaved converter according to the second Docket No. PMDA-13240-PCT 5 embodiment. FIG. 12 is a diagram of the configuration of a second switching converter circuit during a low-load operation mode of the interleaved converter according to the second 5 embodiment. FIG. 13 is a diagram of a configuration example of an interleaved converter according to a third embodiment. FIG. 14 is a diagram explaining operation mode switching conditions corresponding to the magnitude of the 10 load power in the interleaved converter according to the third embodiment. FIG. 15 is a diagram of the configuration of a second switching converter circuit during a low-load operation mode of the interleaved converter according to the third 15 embodiment. FIG. 16 is a diagram of the configuration of third switching converter circuits during an intermediate-load operation mode of the interleaved converter according to the third embodiment. 20 Description of Embodiments [0011] An interleaved converter according to embodiments of the present invention will be explained below with reference to the accompanying drawings. Note that the 25 present invention is not limited by the embodiments explained below. [0012] First Embodiment. FIG. 1 is a diagram of a configuration example of an interleaved converter according to a first embodiment. As 30 shown in FIG. 1, an interleaved converter 50 according to the first embodiment is configured as a two-circuit parallel interleaved converter and includes two switching converter circuits (hereinafter referred to as "first Docket No. PMDA-13240-PCT 6 switching converter circuits") 501 and 502 connected in parallel, a rectifier circuit (a diode bridge) 2 that full wave rectifies an alternating-current voltage output from an alternating-current power supply 1, a smoothing 5 capacitor 3 that smooths a voltage applied to a load 10, and a control circuit 4. [0013] The first switching converter circuit 501 is configured to include an inductor 5a, a switching element 6a, and a diode 7a. The high-voltage side output end of 10 the rectifier circuit 2 and one end of the inductor 5a are connected via an input side switch 101a. The other end of the inductor 5a and the anode of the diode 7a are connected. The switching element 6a is connected between the connection point of the other end of the inductor 5a and 15 the anode of the diode 7a and the GND. [0014] The first switching converter 502 is configured to include an inductor 5b, a switching element 6b, and a diode 7b. The high-voltage side output end of the rectifier circuit 2 and one end of the inductor 5b are 20 connected. The other end of the inductor 5b and the anode of the diode 7b are connected via an output side switch 102a. The switching element 6b is connected between the connection point of the output side switch 102a and the anode of the diode 7a and the GND. 25 [0015] The connection point of the input side switch 101a and the inductor 5a and the connection point of the inductor 5b and the output side switch 102a are connected via an inter-inductor switch 103a. [0016] The control circuit 4 includes a function of 30 subjecting the switching elements 6a and 6b to switching control and controlling the input side switch 101a, the output side switch 102a, and the inter-inductor switch 103a according to operation mode request information, load Docket No. PMDA-13240-PCT 7 voltage information, and information for load power calculation received from the outside. [0017] In this embodiment, the operation mode includes, as operation modes corresponding to load power ranges, a 5 high-load operation mode applied when a power supply amount to the load 10 (hereinafter simply referred to as "load power") is large and a low-load operation mode applied when the load power is smaller than the load power in the high load operation mode. Note that, in this embodiment, 10 switching of the operation mode is carried out according to the magnitude of the load power or operation mode request information. Note that the operation mode request information is information that a user requests, using, for example, a remote controller (not shown in the figure), an 15 apparatus mounted with the interleaved converter 50 according to the first embodiments to provide. [0018] In this embodiment, the load voltage information indicates an average V2 per predetermined time of a load voltage applied to the load 10 (hereinafter simply referred 20 to as "load voltage V2"). The information for load power calculation is information used in calculating load power and includes instantaneous values of a load voltage applied to the load 10 and a load current flowing into the load 10, instantaneous values of an input voltage and an input 25 current input from the alternating-current power supply 1, or the like. The load voltage, the load current, the input voltage, the input current, and the like are detected by a voltage detecting unit and a current detecting unit that are not shown in the figure. Note that the present 30 invention is not limited by a detection method for the voltages and the electric currents by the voltage detecting unit and the current detecting unit and a calculation method for the load power. Docket No. PMDA-13240-PCT 8 [0019] Operations during respective operation modes and operation mode switching control in the interleaved converter 50 according to the first embodiment are explained. First, an operation during the high-load 5 operation mode is explained with reference to FIG. 1 to FIG. 4. FIG. 2 is a diagram of the configuration of the first switching converter circuits during the high-load operation mode of the interleaved converter according to the first embodiment. FIG. 3 is a diagram of current waveforms and 10 PWM signal waveforms for causing switching elements to operate during the high-load operation mode of the interleaved converter according to the first embodiment. FIG. 4 is a diagram of a full-wave rectified voltage waveform, a load voltage waveform, and a supply voltage 15 waveform to a load during the high-load operation mode of the interleaved converter according to the first embodiment. [0020] During the high-load operation mode, as shown in FIG. 2, the control circuit 4 subjects the input side switch 101a and the output side switch 102a to ON control 20 and subjects the inter-inductor switch 103a to OFF control. That is, during the high-load operation mode, as shown in FIG. 1, the first switching converter circuit 501 is configured by the inductor 5a, the switching element 6a, and the diode 7a, the first switching converter circuit 502 25 is configured by the inductor 5b, the switching element 6b, and the diode 7b, and electric currents flow through the paths shown in FIG. 2. In an example shown in FIG. 2, an alternating current flowing into the rectifier circuit 2 from the alternating-current power supply 1 is represented 30 by I, a full-wave rectified current rectified by the rectifier circuit 2 is represented by Il, an electric current flowing to the inductor 5a is represented by Ill, and an electric current flowing to the inductor 5b is Docket No. PMDA-13240-PCT 9 represented by 112. [0021] In this case, as shown in FIG. 3, the control circuit 4 outputs a PWM signal SG11 to the switching element 6a and outputs a PWM signal SG12 to the switching 5 element 6b such that the electric current Ill flowing to the inductor 5a and the electric current 112 flowing to the inductor 5b have a phase difference of 1800 relative to each other. Consequently, a so-called interleave operation is performed in which each of the switching element 6a and 10 the switching element 6b is turned on at every 1800. Therefore, the alternating current I0 flowing into the rectifier circuit 2 from the alternating-current power supply 1 is formed in a sine wave shape while the peaks of the electric current Ill flowing to the inductor 5a and the 15 electric current 112 flowing to the inductor 5b have a phase difference of 1800 relative to each other and thus the power supply power factor is improved. [0022] In this case, a counter electromotive force is generated by switching the electric currents Ill and 112 20 flowing to the inductors 5a and 5b with the switching elements 6a and 6b. Therefore, it is possible to boost the load voltage V2 with respect to a rectified voltage V1. Note that the control circuit 4 includes a function of changing the carrier frequencies of the PWM signals SG11 25 and SG12 to thereby adjust the load voltage V2 to fall within a range of a target load voltage set in advance. [0023] An operation during the low-load operation mode in the interleaved converter 50 according to the first embodiment is explained with reference to FIG. 5 to FIG. 7. 30 FIG. 5 is a diagram of the configuration of a second switching converter circuit during the low-load operation mode of the interleaved converter according to the first Docket No. PMDA-13240-PCT 10 embodiment. FIG. 6 is a diagram of current waveforms and PWM signal waveforms for causing the switching elements to operate during the high-load operation mode of the interleaved converter according to the first embodiment. 5 FIG. 7 is a diagram of a full-wave rectified voltage waveform, a load voltage waveform, and a supply voltage waveform to a load during the low-load operation mode of the interleaved converter according to the first embodiment. [0024] During the low load operation mode, as shown in 10 FIG. 5, the control circuit 4 subjects the input side switch 101a and the output side switch 102a to OFF control and subjects the inter-inductor switch 103a to ON control. That is, during the low-load operation mode, as shown in FIG. 5, a series inductor circuit 8a is configured by 15 connecting the inductor 5a and the inductor 5b in series, a second switching converter circuit 601 is configured by the series inductor circuit 8a, the switching element 6a, and the diode 7a, and the electric current Il flows through the path shown in FIG. 5. 20 [0025] In this case, as shown in FIG. 6, the control circuit 4 outputs the PWM signal SG11 to the switching element 6a to cause the switching element 6a to perform an ON/OFF operation. The control circuit 4 stops the output of the PWM signal SG12 to the switching element 6b to 25 disable the switching element 6b. Consequently, it is possible to attain a reduction in the switching loss while effectively utilizing the inductors 5a and 5b. The control circuit 4 includes a function of changing the carrier frequency of the PWM signal SG11 to thereby adjust the load 30 voltage V2 to fall within the range of the target load voltage set in advance as in the high-load operation mode. The control circuit 4 includes a function of causing the pulse width of the PWM signal SG11 variable to thereby Docket No. PMDA-13240-PCT 11 change the DUTY ratio of the PWM signal SG11. Consequently, it is possible to bring the alternating current I0 flowing into the rectifier circuit 2 from the alternating-current power supply 1 close to a sine wave and improve the power 5 supply power factor. [0026] As explained above, in this embodiment, in the high-load operation mode, power supply to the load 10 is performed by a so-called interleave operation by the two first switching converter circuits 501 and 502. In the 10 low-load operation mode, power supply to the load 10 is performed by connecting the inductors 5a and 5b in series to configure the series inductor circuit 8a and configuring the second switching converter circuit 601 and causing the second switching converter circuit 601 to operate. 15 Consequently, in the low-load operation mode, the switching element 6b can be disabled. Therefore, it is possible to attain a reduction in the switching loss while effectively utilizing the inductors 5a and 5b and perform appropriate power supply while further reducing the switching loss than 20 in the high-load operation mode. An inductance value of a current path is increased by connecting the two inductors 5a and 5b in series. Therefore, it is possible to improve the boosting ability. Further, it is possible to reduce the carrier frequency of the PWM signal SG11 without 25 reducing the load voltage V2. Therefore, it is possible to realize a further reduction in the switching loss. [0027] Switching control for the high-load operation mode and the low-load operation mode in the interleaved converter according to the first embodiment is explained. 30 [0028] In this embodiment, as explained above, the switching of the operation mode is carried out according to the magnitude of the load power or the operation mode request information. First, operation mode switching Docket No. PMDA-13240-PCT 12 conditions corresponding to the magnitude of the load power are explained with reference to FIG. 8. FIG. 8 is a diagram explaining the operation mode switching conditions corresponding to the magnitude of the load power in the 5 interleaved converter according to the first embodiment. [0029] As explained above, the control circuit 4 calculates the load power using the information for load power calculation including the instantaneous values of the load voltage applied to the load 10 and the load current 10 flowing into the load 10 or the instantaneous values of the input voltage and the input current input from the alternating-current power supply 1. The control circuit 4 compares the calculated load voltage with a first load power threshold PL and a second load power threshold PH 15 shown in FIG. 8 to thereby determine whether the switching of the operation mode is performed (hereinafter referred to as "operation mode switching determination"). [0030] As shown in FIG. 8, during the high-load operation mode, when the load power falls below the first 20 load power threshold PL set in advance, the operation mode shifts to the low-load operation mode. On the other hand, during the low-load operation mode, when the load power exceeds the second load power threshold PH set in advance, the operation mode shifts to the high-load operation mode. 25 When the load power does not meet both the conditions, the operation mode is not changed. In this embodiment, the first load power threshold PL for shifting the operation mode from the high-load operation mode to the low-load operation mode is set to a value lower than the second load 30 power threshold PH for shifting the operation mode from the low-load operation mode to the high-load operation mode (PL<PH). By setting the first load power threshold PL and the second load power threshold PH in this way, it is Docket No. PMDA-13240-PCT 13 possible to prevent the high-load operation mode and the low-load operation mode from being frequently switched. It is possible to perform stable switching control for the operation mode. 5 [0031] Operation mode switching control in the interleaved converter 50 according to the first embodiment is explained with reference to FIG. 9. FIG. 9 is a flowchart explaining an example of the operation mode switching control in the interleaved converter according to 10 the first embodiment. [0032] At the start of control of the interleaved converter 50, the control circuit 4 acquires operation mode request information (step ST101) and determines the presence or absence of an operation mode request (step 15 ST102). [0033] When the operation mode request is present (Yes at step ST102), that is, when the operation mode is changed from the present operation mode, the control circuit 4 shifts to the requested operation mode (step ST103), 20 controls the input side switch 101a, the output side switch 102a, and the inter-inductor switch 103a, and performs switching control in the operation modes. [0034] That is, when shifting the operation mode from the high-load operation mode to the low-load operation mode, 25 the control circuit 4 controls the input side switch 101a and the output side switch 102a to switch from ON to OFF and controls the inter-inductor switch 103a to switch from OFF to ON to configure the second switching converter circuit 601, outputs the PWM signal SG11 to the switching 30 element 6a to cause the switching element 6a to perform an ON/OFF operation, and stops the output of the PWM signal SG12 to the switching element 6b to disable the switching element 6b. Docket No. PMDA-13240-PCT 14 [0035] When shifting the operation mode from the low load operation mode to the high-load operation mode, the control circuit 4 controls the input side switch 101a and the output side switch 102a to switch from OFF to ON and 5 controls the inter-inductor switch 103a to switch from ON to OFF to configure the first switching converter circuits 501 and 502, outputs the PWM signal SG11 to the switching element 6a, and outputs the PWM signal SG12 to the switching element 6b. 10 [0036] When the operation mode request is absent (No at step ST102), that is, when the operation mode is not changed from the present operation mode, the control circuit 4 acquires the information for load power calculation (step ST104) and calculates the load power 15 (step ST105). Then, the control circuit 4 carries out the operation mode switching determination described above and determines whether the operation mode switching conditions shown in FIG. 8 are met (step ST106). [0037] When the operation mode switching conditions are 20 not met (No at step ST106), the control circuit 4 determines whether the operation mode switching control is to be ended (step ST110). When the operation mode switching control is to be ended (Yes at step ST110), the control circuit 4 ends the operation mode switching control 25 (step ST111). When the operation mode switching control is not to be ended (No at step ST110), the control circuit 4 returns to the processing at step ST101 and repeatedly carries out the processing at step ST101 to step ST110. Note that the present invention is not limited by this 30 operation mode switching control end determining method at step ST110. [0038] When the operation mode switching conditions are met (Yes at step ST106), the control circuit 4 shifts the Docket No. PMDA-13240-PCT 15 operation mode to the requested operation mode (step ST103). [0039] After the shift of the operation mode (step ST103), the control circuit 4 acquires the load voltage information (step ST107) and determines whether the load 5 voltage V2 is within a target load voltage range set in advance (step ST108). [0040] When the load voltage V2 is outside the target load voltage range (No at step ST108), the control circuit 4 changes the carrier frequencies of the PWM signals SG11 10 and SG12 (step ST109), returns to the processing at step ST107, and repeatedly carries out the processing at step ST107 and step ST108 until the load voltage V2 falls within the target load voltage range (Yes at step ST108). [0041] When the load voltage V2 is within the target 15 load voltage range (Yes at step ST108), the control circuit 4 determines whether the operation mode switching control is to be ended (step ST110). When the operation mode switching control is to be ended (Yes at step ST110), the control circuit 4 ends the operation mode switching control 20 (step ST111). When the operation mode switching control is not to be ended (No at step ST110), the control circuit 4 returns to the processing at step ST101 and repeatedly carries out the processing at step ST101 to step ST110. [0042] As explained above, with the interleaved 25 converter according to the first embodiment, as the operation mode, the high-load operation mode in which the load power is large and the low-load operation mode in which the load power is smaller than the load power in the high-load operation mode are provided. In the high-load 30 operation mode, two first switching converter circuits are each configured by one inductor, one switching element, and one diode. These two first switching converter circuits are caused to perform an interleave operation to perform Docket No. PMDA-13240-PCT 16 power supply to the load. In the low-load operation mode, two inductors are connected in series to configure one series inductor circuit. One second switching converter circuit is configured by this series inductor circuit, one 5 switching element, and one diode. This second switching converter circuit is caused to operate to perform power supply to the load. Therefore, it is possible to effectively utilize the inductors even in the low-power load. 10 [0043] In the low-load operation mode, one switching element not configuring the second switching converter circuit can be disabled. Therefore, it is possible to perform appropriate power supply while further reducing the switching loss than in the high-load operation mode. 15 [0044] The inductance value of the current path is increased by connecting two inductors in series. Therefore, it is possible to improve the boosting ability. It is possible to reduce the carrier frequency of the PWM signal for causing the switching element configuring the second 20 switching converter circuit to operate without reducing the load voltage. Therefore, it is possible to further reduce the switching loss. [0045] Therefore, it is possible to further improve converter efficiency in the low-power load and obtain an 25 interleaved converter that enables a more highly efficient operation. [0046] As the conditions for switching the operation mode, the first load power threshold PL for shifting the operation mode from the high-load operation mode to the 30 low-load operation mode is set to the value lower than the second load power threshold PH for shifting the operation mode from the low-load operation mode to the high-load operation mode (PL<PH). Therefore, it is possible to Docket No. PMDA-13240-PCT 17 prevent the high-load operation mode and the low-load operation mode from being frequently switched and perform stable switching control for the operation mode. [0047] The user can also select the operation mode. 5 Therefore, it is possible to perform a more flexible operation. For example, the user can intentionally reduce the load power and operate the interleaved converter. [0048] Second Embodiment. In the example explained in the first embodiment, the 10 interleaved converter is configured by two switching converter circuits connected in parallel. In the present embodiment, an example is explained in which an interleaved converter is configured by three switching converter circuits connected in parallel. 15 [0049] FIG. 10 is a diagram showing a configuration example of an interleaved converter according to the second embodiment. Note that components same as or equivalent to the components in the first embodiment are denoted by the same reference numerals and signs and detailed explanation 20 of the components is omitted. [0050] As shown in FIG. 10, in an interleaved converter 51 according to the second embodiment, the interleaved converter 50 according to the first embodiment is configured as a three-circuit parallel interleaved 25 converter. In addition to the configuration explained in the first embodiment, the interleaved converter 51 includes a first switching converter circuit 503 configured to include an inductor 5c, a switching element 6c, and a diode 7c. In the first switching converter circuit 503, the 30 high-voltage side output terminal of the rectifier circuit 2 and one end of the inductor 5c are connected via an input side switch 101b, the other end of the inductor 5c and the anode of the diode 7c are connected via an output side Docket No. PMDA-13240-PCT 18 switch 102b, and the switching element 6c is connected between the connection point of the other end of the inductor 5c and the anode of the diode 7c and the GND. [0051] The connection point of the input side switch 5 101a and the inductor 5a and the connection point of the inductor 5c and the output side switch 102b are connected via the inter-inductor switch 103a. The connection point of the input side switch 101b and the inductor 5c and the connection point of the inductor 5b and the output side 10 switch 102a are connected via an inter-inductor switch 103b. [0052] A control circuit 4a includes a function of subjecting the switching elements 6a, 6b, and 6c to switching control and controlling the input side switches 101a and 101b, the output side switches 102a and 102b, and 15 the inter-inductor switches 103a and 103b according to operation mode request information, load voltage information, and information for load power calculation received from the outside. [0053] Operations during respective operation modes in 20 the interleaved converter 51 according to the second embodiment are explained. First, an operation during the high-load operation mode is explained with reference to FIG. 11. FIG. 11 is a diagram of the configuration of the first switching converter circuits during the high-load operation 25 mode of the interleaved converter according to the second embodiment. [0054] During the high-load operation mode, as shown in FIG. 11, the control circuit 4a subjects the input side switches 101a and 101b and the output side switches 102a 30 and 102b to ON control and subjects the inter-inductor switches 103a and 103b to OFF control. That is, during the high-load operation mode, as shown in FIG. 11, the first switching converter circuit 501 is configured by the Docket No. PMDA-13240-PCT 19 inductor 5a, the switching element 6a, and the diode 7a, the first switching converter circuit 502 is configured by the inductor 5b, the switching element 6b, and the diode 7b, the first switching converter circuit 503 is configured by 5 the inductor 5c, the switching element 6c, and the diode 7c, and electric currents flow through the paths shown in FIG. 11. In an example shown in FIG. 11, an alternating current flowing into the rectifier circuit 2 from the alternating current power supply 1 is represented by I, a full-wave 10 rectified current rectified by the rectifier circuit 2 is represented by Il, an electric current flowing to the inductor 5a is represented by Ill, an electric current flowing to the inductor 5b is represented by 112, and an electric current flowing to the inductor 5c is represented 15 by 113. [0055] In this case, the control circuit 4a outputs the PWM signal SG11 to the switching element 6a, outputs the PWM signal SG12 to the switching element 6b, and outputs a PWM signal SG13 to the switching element 6c such that the 20 electric current Ill flowing to the inductor 5a, the electric current 112 flowing to the inductor 5b, and the electric current 113 flowing to the inductor 5c have a phase difference of 1200 relative to each other. Consequently, a so-called interleave operation is performed 25 in which each of the switching element 6a, the switching element 6b, and the switching element 6c is turned on at every 1200. Therefore, the alternating current I0 flowing into the rectifier circuit 2 from the alternating-current power supply 1 is formed in a sine wave shape while the 30 peaks of the electric current Ill flowing to the inductor 5a, the electric current 112 flowing to the inductor 5b, and the electric current 113 flowing to the inductor 5c Docket No. PMDA-13240-PCT 20 have a phase difference of 1200 relative to each other and thus the power supply power factor is improved. [0056] In this case, a counter electromotive force is generated by switching the electric currents Ill, 112, and 5 113 flowing to the inductors 5a, 5b, and 5c with the switching elements 6a, 6b, and 6c. Therefore, it is possible to boost the load voltage V2 with respect to the rectified voltage V1. Note that the control circuit 4a includes a function of changing the carrier frequencies of 10 the PWM signals SG11, SG12, and SG13 to thereby adjust the load voltage V2 to fall within a range of a target load voltage set in advance. [0057] An operation during the low-load operation mode in the interleaved converter 51 according to the second 15 embodiment is explained with reference to FIG. 12. FIG. 12 is a diagram of the configuration of a second switching converter circuit during the low-load operation mode of the interleaved converter according to the second embodiment. [0058] During the low-load operation mode, as shown in 20 FIG. 12, the control circuit 4a subjects the input side switches 101a and 101b and the output side switches 102a and 102b to OFF control and subjects the inter-inductor switches 103a and 103b to ON control. That is, during the low-load operation mode, as shown in FIG. 12, a series 25 inductor circuit 8b is configured by connecting the inductor 5a, the inductor 5b, and the inductor 5c in series, a second switching converter circuit 602 is configured by the series inductor circuit 8b, the switching element 6a, and the diode 7a, and the electric current Il flows through 30 the path shown in FIG. 12. [0059] In this case, the control circuit 4a outputs the PWM signal SG11 to the switching element 6a to cause the switching element 6a to perform an ON/OFF operation. The Docket No. PMDA-13240-PCT 21 control circuit 4a stops the output of the PWM signals SG12 and SG13 to the switching elements 6b and 6c to disable the switching elements 6b and 6c. Consequently, it is possible to attain a reduction in the switching loss while 5 effectively utilizing the inductors 5a, 5b, and 5c. The control circuit 4a includes a function of changing the carrier frequency of the PWM signal SG11 to thereby adjust the load voltage V2 to fall within the range of the target load voltage set in advance as in the high-load operation 10 mode. The control circuit 4a includes a function of causing the pulse width of the PWM signal SG11 variable to thereby change the DUTY ratio of the PWM signal SG11. Consequently, it is possible to bring the alternating current I0 flowing into the rectifier circuit 2 from the 15 alternating-current power supply 1 close to a sine wave and improve the power supply power factor. [0060] As explained above, in this embodiment, in the high-load operation mode, power supply to the load 10 is performed by a so-called interleave operation by the three 20 first switching converter circuits 501, 502, and 503. In the low-load operation mode, power supply to the load 10 is performed by connecting the inductors 5a, 5b, and 5c in series to configure the series inductor circuit 8b and configuring the second switching converter circuit 602 and 25 causing the second switching converter circuit 602 to operate. Consequently, in the low-load operation mode, the switching elements 6b and 6c can be disabled. Therefore, it is possible to attain a reduction in the switching loss while effectively utilizing the inductors 5a, 5b, and 5c 30 and perform appropriate power supply while further reducing the switching loss than in the high-load operation mode. An inductance value of a current path is increased by connecting the three inductors 5a, 5b, and 5c in series. Docket No. PMDA-13240-PCT 22 Therefore, it is possible to improve the boosting ability. Further, it is possible to reduce the carrier frequency of the PWM signal SG11 without reducing the load voltage V2. Therefore, it is possible to realize a further reduction in 5 the switching loss. [0061] Note that switching control for the high-load operation mode and the low-load operation mode in the interleaved converter according to the second embodiment is the same as the switching control in the first embodiment. 10 Therefore, explanation of the switching control is omitted. [0062] As explained above, with the interleaved converter in the second embodiment, it is possible to obtain effects same as the effects in the first embodiment even when the interleaved converter is configured as the 15 three-circuit parallel interleaved converter by three switching converter circuits connected in parallel. [0063] Third Embodiment. In the examples explained in the first embodiment and the second embodiment, the interleaved converter is 20 configured by two or three switching converter circuits connected in parallel. In the present embodiment, an example is explained in which an interleaved converter is configured by four or more switching converter circuits connected in parallel. 25 [0064] FIG. 13 is a diagram showing a configuration example of an interleaved converter according to the third embodiment. Note that components same as or equivalent to the components in the first embodiment or the second embodiment are denoted by the same reference numerals and 30 signs and detailed explanation of the components is omitted. In the example shown in FIG. 13, a case where the number of first switching converter circuits is four is illustrated. [0065] In the example shown in FIG. 13, an interleaved Docket No. PMDA-13240-PCT 23 converter 52 according to the third embodiment is configured as a four-circuit parallel interleaved converter. In addition to the configuration explained in the second embodiment, the interleaved converter 52 includes a first 5 switching converter circuit 504 configured to include an inductor 5d, a switching element 6d, and a diode 7d. In the first switching converter circuit 504, the high-voltage side output terminal of the rectifier circuit 2 and one end of the inductor 5d are connected via an input side switch 10 101c, the other end of the inductor 5d and the anode of the diode 7d are connected via an output side switch 102c, and the switching element 6d is connected between the connection point of the other end of the inductor 5d and the anode of the diode 7d and the GND. 15 [0066] The connection point of the input side switch 101a and the inductor 5a and the connection point of the inductor 5d and the output side switch 102c are connected via the inter-inductor switch 103a. The connection point of the input side switch 101c and the inductor 5d and the 20 connection point of the inductor 5c and the output side switch 102b are connected via the inter-inductor switch 103c. The connection point of the input side switch 101b and the inductor 5c and the connection point of the inductor 5b and the output side switch 102a are connected 25 via the inter-inductor switch 103b. [0067] A control circuit 4b includes a function of subjecting the switching elements 6a, 6b, 6c, and 6d to switching control and controlling the input side switches 101a, 101b, and 101c, the output side switches 102a, 102b, 30 and 102c, and the inter-inductor switches 103a, 103b, and 103c according to operation mode request information, load voltage information, and information for load power calculation received from the outside. Docket No. PMDA-13240-PCT 24 [0068] FIG. 14 is a diagram explaining operation mode switching conditions corresponding to the magnitude of the load power in the interleaved converter according to the third embodiment. In this embodiment, in addition to the 5 high-load operation mode and the low-load operation mode explained in the first embodiment, the operation mode includes an intermediate-load operation mode in which the load power range is lower than a load power range in the high-load operation mode and higher than a load power range 10 in the low-load operation mode. [0069] As shown in FIG. 14, during the high-load operation mode, when the load power falls below a first load power threshold PHM set in advance, the operation mode shifts to the intermediate-load operation mode. On the 15 other hand, during the intermediate-load operation mode, when the load power exceeds a second load power threshold PHH set in advance, the operation mode shifts to the high load operation mode. During the intermediate-load operation mode, when the load power falls below a third 20 load power threshold PLL set in advance, the operation mode shifts to the low-load operation mode. On the other hand, during the low-load operation mode, when the load power exceeds a fourth load power threshold PLM set in advance, the operation mode shifts to the intermediate-load 25 operation mode. When the load power does not meet all the conditions, the operation mode is not changed. [0070] In this embodiment, the first load power threshold PHM for shifting the operation mode from the high-load operation mode to the intermediate-load operation 30 mode is set to a value lower than the second load power threshold PHH for shifting the operation mode from the intermediate-load operation mode to the high-load operation mode (PHM<PHH). The third load power threshold PLL for Docket No. PMDA-13240-PCT 25 shifting the operation mode from the intermediate-load operation mode to the low-load operation mode is set to a value lower than the fourth load power threshold PLM for shifting the operation mode from the low-load operation 5 mode to the intermediate-load operation mode (PLL<PLM). [0071] By setting the first load power threshold PHM, the second load power threshold PHH, the third load power threshold PLL, and the fourth load power threshold PLM in this way, it is possible to prevent the operation modes 10 adjacent to each other (i.e., the high-load operation mode and the intermediate-load operation mode and the intermediate-load operation mode and the low-load operation mode) from being frequently switched. It is possible to perform stable switching of the operation mode. 15 [0072] Operations during the respective operation modes in the interleaved converter 52 according to the third embodiment are explained. First, an operation during the high-load operation mode is explained with reference to FIG. 13. 20 [0073] During the high-load operation mode, as shown in FIG. 13, the control circuit 4b subjects the input side switches 101a, 101b, and 101c and the output side switches 102a, 102b, and 102c to ON control and subjects the inter inductor switches 103a, 103b, and 103c to OFF control. 25 That is, during the high-load operation mode, as shown in FIG. 13, the first switching converter circuit 501 is configured by the inductor 5a, the switching element 6a, and the diode 7a, the first switching converter circuit 502 is configured by the inductor 5b, the switching element 6b, 30 and the diode 7b, the first switching converter circuit 503 is configured by the inductor 5c, the switching element 6c, and the diode 7c, and the first switching converter circuit 504 is configured by the inductor 5d, the switching element Docket No. PMDA-13240-PCT 26 6d, and the diode 7d. [0074] In this case, the control circuit 4b outputs the PWM signal SG11 to the switching element 6a, outputs the PWM signal SG12 to the switching element 6b, outputs the 5 PWM signal SG13 to the switching element 6c, and outputs a PWM signal SG14 to the switching element 6d such that the electric currents flowing to the inductors 5a, 5b, 5c, and 5d have a phase difference of 900 relative to each other. Consequently, a so-called interleave operation is performed 10 in which each of the switching element 6a, the switching element 6b, the switching element 6c, and the switching element 6d is turned on at every 900. Therefore, the alternating current flowing into the rectifier circuit 2 from the alternating-current power supply 1 is formed in a 15 sine wave shape while the peaks of the electric currents flowing to the inductors 5a, 5b, 5c, and 5d have a phase difference of 900 relative to each other and thus the power supply power factor is improved. [0075] In this case, a counter electromotive force is 20 generated by switching the inductors 5a, 5b, 5c, and 5d with the switching elements 6a, 6b, 6c, and 6d. Therefore, it is possible to boost the load voltage V2 with respect to the rectified voltage V1. Note that the control circuit 4b includes a function of changing the carrier frequencies of 25 the PWM signals SG11, SG12, SG13, and SG14 to thereby adjust the load voltage V2 to fall within a range of a target load voltage set in advance. [0076] An operation during the low-load operation mode in the interleaved converter 52 according to the third 30 embodiment is explained with reference to FIG. 15. FIG. 15 is a diagram of the configuration of a second switching converter circuit during the low-load operation mode of the Docket No. PMDA-13240-PCT 27 interleaved converter according to the third embodiment. [0077] During the low-load operation mode, as shown in FIG. 15, the control circuit 4b subjects the input side switches 101a, 101b, and 101c and the output side switches 5 102a, 102b, and 102c to OFF control and subjects the inter inductor switches 103a, 103b, and 103c to ON control. That is, during the low-load operation mode, as shown in FIG. 15, a series inductor circuit 8c is configured by connecting the inductor 5a, the inductor 5b, the inductor 5c, and the 10 inductor 5d in series, and a second switching converter circuit 603 is configured by the series inductor circuit 8c, the switching element 6a, and the diode 7a. [0078] In this case, the control circuit 4b outputs the PWM signal SG11 to the switching element 6a to cause the 15 switching element 6a to perform an ON/OFF operation. The control circuit 4b stops the output of the PWM signals SG12, SG13, and SG14 to the switching elements 6b, 6c, and 6d to disable the switching elements 6b, 6c, and 6d. Consequently, it is possible to attain a reduction in the 20 switching loss while effectively utilizing the inductors 5a, 5b, 5c, and 5d. The control circuit 4b includes a function of changing the carrier frequency of the PWM signal SG11 to thereby adjust the load voltage V2 to fall within the range of the target load voltage set in advance as in the high 25 load operation mode. The control circuit 4b includes a function of causing the pulse width of the PWM signal SG11 variable to thereby change the DUTY ratio of the PWM signal SG11. Consequently, it is possible to bring the alternating current flowing into the rectifier circuit 2 30 from the alternating-current power supply 1 close to a sine wave and improve the power supply power factor. [0079] An operation during the intermediate-load operation mode in the interleaved converter 52 according to Docket No. PMDA-13240-PCT 28 the third embodiment is explained with reference to FIG. 16. FIG. 16 is a diagram of the configuration of third switching converter circuits during the intermediate-load operation mode of the interleaved converter according to 5 the third embodiment. [0080] During the intermediate-load operation mode, as shown in FIG. 16, the control circuit 4b subjects the input side switches 101a and 101b, the output side switches 102a and 102c, and the inter-inductor switch 103c to OFF control 10 and subjects the input side switch 101c, the output side switch 102b, and the inter-inductor switches 103a and 103b to ON control. That is, during the intermediate-load operation mode, as shown in FIG. 16, a series inductor circuit 8d is configured by connecting the inductor 5a and 15 the inductor 5d in series and a third switching converter circuit 701 is configured by the series inductor circuit 8d, the switching element 6a, and the diode 7a. Moreover, a series inductor circuit 8e is configured by connecting the inductor 5b and the inductor 5c in series and a third 20 switching converter circuit 702 is configured by the series inductor circuit 8e, the switching element 6c, and the diode 7c. [0081] In this case, the control circuit 4b outputs the PWM signal SG11 to the switching element 6a to cause the 25 switching element 6a to perform an ON/OFF operation and outputs the PWM signal SG13 to the switching element 6c to cause the switching element 6c to perform an ON/OFF operation. The control circuit 4b stops the output of the PWM signals SG12 and SG14 to the switching elements 6b and 30 6d to disable the switching elements 6b and 6d. Consequently, during the intermediate-load operation mode also, it is possible to attain a reduction in the switching loss while effectively utilizing the inductors 5a, 5b, 5c, Docket No. PMDA-13240-PCT 29 and 5d. The control circuit 4b outputs the PWM signal SG11 to the switching element 6a and outputs the PWM signal SG13 to the switching element 6c such that the electric current flowing to the series inductor circuit 8d and the electric 5 current flowing to the series inductor circuit 8e have a phase difference of 1800 relative to each other. Consequently, a so-called interleave operation is performed in which each of the switching element 6a and the switching element 6c is turned on at every 1800. Therefore, the 10 alternating current flowing into the rectifier circuit 2 from the alternating-current power supply 1 is formed in a sine wave shape while the peaks of the electric current flowing to the series inductor circuit 8d and the electric current flowing to the series inductor circuit 8e have a 15 phase difference of 1800 relative to each other and thus the power supply power factor is improved. [0082] As explained above, in this embodiment, in the high-load operation mode, power supply to the load 10 is performed by a so-called interleave operation by the four 20 first switching converter circuits 501, 502, 503, and 504. In the low-load operation mode, power supply to the load 10 is performed by connecting the inductors 5a, 5b, 5c, and 5d in series to configure the series inductor circuit 8c and configuring the second switching converter circuit 603 and 25 causing the second switching converter circuit 603 to operate. Consequently, in the low-load operation mode, the switching elements 6b, 6c, and 6d can be disabled. Therefore, it is possible to attain a reduction in the switching loss while effectively utilizing the inductors 5a, 30 5b, 5c, and 5d and perform appropriate power supply while further reducing the switching loss than in the high-load operation mode. An inductance value of a current path is Docket No. PMDA-13240-PCT 30 increased by connecting the four inductors 5a, 5b, 5c, and 5d in series. Therefore, it is possible to improve the boosting ability. Further, it is possible to reduce the carrier frequency of the PWM signal SG11 without reducing 5 the load voltage V2. Therefore, it is possible to realize a further reduction in the switching loss. [0083] Further, in this embodiment, in addition to the high-load operation mode and the low-load operation mode explained in the first embodiment, the operation mode 10 includes the intermediate-load operation mode in which the load power range is lower than the load power range in the high-load operation mode and higher than the load power range in the low-load operation mode. In the intermediate load operation mode also, the inductors 5a and 5d are 15 connected in series to configure the series inductor circuit 8d, the inductors 5b and 5c are connected in series to configure the series inductor circuit 8e, the two third switching converter circuits 701 and 702 are configured, and power supply to the load 10 is performed by a so-called 20 interleave operation by the two third switching converter circuits 701 and 702. Consequently, in the intermediate load operation mode, the switching elements 6b and 6d can be disabled. Therefore, it is possible to attain a reduction in the switching loss while effectively utilizing 25 the inductors 5a, 5b, 5c, and 5d. It is possible to perform more appropriate power supply according to the magnitude of the load power. [0084] Note that, in the example explained with reference to FIG. 13 to FIG. 16, the interleaved converter 30 52 according to the third embodiment is configured as the four-circuit parallel interleaved converter. However, the interleaved converter 52 can also be configured as an n circuit parallel interleaved converter configured by n (n Docket No. PMDA-13240-PCT 31 is an integer equal to or larger than 2) switching converter circuits connected in parallel. Operations during the respective operation modes in this case are explained below. 5 [0085] A control circuit includes a function of subjecting n switching elements to switching control and controlling input side switches, output side switches, and inter-inductor switches for configuring a first switching converter circuit in the high-load operation mode, a second 10 switching converter circuit in the low-load operation mode, and a third switching converter circuit in the intermediate-load operation mode according to operation mode request information, load voltage information, and information for load power calculation received from the 15 outside. [0086] During the high-load operation mode, the control circuit controls the input side switches, the output side switches, and the inter-inductor switches and configures n first switching converter circuits using one inductor, one 20 switching element, and one diode for each of the n first switching converter circuits. [0087] In this case, the control circuit outputs PWM signals respectively to the switching elements such that the electric currents flowing to n inductors have a phase 25 difference of (360 0 /n) relative to each other. Consequently, a so-called interleave operation is performed in which each of the switching elements is turned on at every (360 0 /n) . Therefore, an alternating current flowing into a rectifier circuit from an alternating-current power 30 supply is formed in a sine wave shape while the peaks of the electric currents flowing to the inductors have a phase difference of (360 0 /n) relative to each other and thus the Docket No. PMDA-13240-PCT 32 power supply power factor is improved. [0088] During the low-load operation mode, the control circuit controls the input side switches, the output side switches, and the inter-inductor switches, connects the n 5 inductors in series to configure one series inductor circuit, and configures one second switching converter using the series conductor circuit, one switching element, and one diode. [0089] In this case, the control circuit outputs a PWM 10 signal to the switching element configuring the second switching converter to cause the switching element to perform an ON/OFF operation and stops the output of PWM signals to the other switching elements to disable the switching elements. Consequently, it is possible to attain 15 a reduction in the switching loss while effectively utilizing the n inductors. The control circuit changes the carrier frequencies of the PWM signals to thereby adjust a load voltage to fall within a range of a target load voltage set in advance. The control circuit causes the 20 pulse width of the PWM signal variable to change the DUTY ratio of the PWM signal to bring the alternating current flowing into the rectifier circuit from the alternating current power supply close to a sine wave and improve the power supply power factor. 25 [0090] During the intermediate-load operation mode, the control circuit controls the input side switches, the output side switches, and the inter-inductor switches, connects m (m is 1 and divisors of n other than n) inductors in series to configure (n/m) series inductor 30 circuits, and configures (n/m) third switching converter circuits using one of the series inductor circuits, one switching element, and one diode for each of the third switching converter circuits. Docket No. PMDA-13240-PCT 33 [0091] In this case, the control circuit outputs PWM signals respectively to the switching elements configuring the (n/m) third switching converter circuits to cause the switching elements to perform an ON/OFF operation and stops 5 the output of PWM signals to the other switching elements to disable the switching elements. Consequently, during the intermediate-load operation mode also, it is possible to attain a reduction in the switching loss while effectively utilizing the n inductors. 10 [0092] The control circuit outputs the PWM signals respectively to the switching elements configuring the (n/m) third switching converter circuits such that the electric currents flowing to the series inductor circuits have a phase difference of (360 0 /(n/m)) relative to each 15 other. Consequently, a so-called interleave operation is performed in which each of the switching elements is turned on at every (3600/ (n/m) ). Therefore, an alternating current flowing into a rectifier circuit from an alternating-current power supply is formed in a sine wave 20 shape while the peaks of the electric currents flowing to the (n/m) series inductor circuits have a phase difference of (3600/ (n/m) ) relative to each other and thus the power supply power factor is improved. [0093] As explained above, with the interleaved 25 converter according to the third embodiment, when the interleaved converter is configured as the n-circuit parallel interleaved converter including n (n is an integer equal to or larger than 2) switching converter circuits connected in parallel, in addition to the high-load 30 operation mode and the low-load operation mode explained in the first embodiment and the second embodiment, the operation mode includes the intermediate-load operation Docket No. PMDA-13240-PCT 34 mode in which the load power range is lower than the load power range in the high-load operation mode and higher than the load power range in the low-load operation mode. In the high-load operation mode, n first switching converter 5 circuits are each configured by one inductor, one switching element, and one diode and the n first switching converter circuits are caused to perform the interleave operation to perform power supply to a load. In the low-load operation mode, n inductors are connected in series to configure one 10 series inductor circuit, one second switching converter is configured using the series inductor circuit, one switching element, and one diode, and the second switching converter circuit is caused to operate to perform power supply to the load. In the intermediate-load operation mode, m (m is 1 15 and divisors of n other than n) inductors are connected in series to configure (n/m) series inductor circuits, (n/m) third switching converter circuits are configured using one of the series inductor circuits, one switching element, and one diode for each of the (n/m) third switching converter 20 circuits, and the (n/m) third switching converter circuits are caused to operate to perform power supply to the load. Therefore, it is possible to effectively utilize the inductors in all the operation modes. [0094] During the intermediate-load operation mode also, 25 (n-(n/m)) switching elements not configuring the (n/m) third switching converter circuits can be disabled. Therefore, it is possible to attain a reduction in the switching loss while effectively utilizing the n inductors. [0095] During the intermediate-load operation mode also, 30 an inductance value of a current path is increased by connecting the m inductors in series. Therefore, it is possible to improve the boosting ability. Further, it is possible to reduce the carrier frequencies of the PWM Docket No. PMDA-13240-PCT 35 signals for causing the switching elements configuring the third switching converter circuits to operate without reducing a load voltage. Therefore, it is possible to further reduce the switching loss. 5 [0096] That is, because the operation mode includes the intermediate-load operation mode, it is possible to obtain an interleaved converter that enables a more highly efficient operation. It is possible to perform more appropriate power supply according to the magnitude of the 10 load power. [0097] As conditions for switching the operation mode, the first load power threshold PHM for shifting the operation mode from the high-load operation mode to the intermediate-load operation mode is set to a value lower 15 than the second load power threshold PHH for shifting the operation mode from the intermediate-load operation mode to the high-load operation mode (PHM<PHH). The third load power threshold PLL for shifting the operation mode from the intermediate-load operation mode to the low-load 20 operation mode is set to a value lower than the fourth load power threshold PLM for shifting the operation mode from the low-load operation mode to the intermediate-load operation mode (PLL<PLM). Consequently, it is possible to prevent the operation mode from being frequently switched 25 and perform stable switching control for the operation mode. [0098] As in the first embodiment and the second embodiment, by allowing the user to select the operation mode, it is possible to perform a more flexible operation. For example, the user can intentionally reduce the load 30 power and operate the interleaved converter. [0099] In the examples explained in the embodiment explained above, the operation mode includes one intermediate load operation mode. However, the number of Docket No. PMDA-13240-PCT 36 intermediate-load operation modes is not limited to this. The operation mode can include two or more intermediate load operation modes. In this case, the configuration of the third switching converter circuit is not one either. 5 For example, by providing an intermediate-load operation mode in which (n/ml) third switching converter circuits are configured by connecting ml inductors in series and a plurality of (two) intermediate-load operation modes in each of which (n/m2) third switching converter circuits are 10 configured by connecting m2 (m2#ml) inductors in series, it is possible to perform more appropriate power supply corresponding to the magnitude of the load power. [0100] Note that the configurations explained in the embodiments are examples of the configuration of the 15 present invention. It goes without saying that the configurations can be combined with other publicly-known technologies or can be changed by, for example, omitting a part thereof without departing from the spirit of the present invention. 20 Reference Signs List [0101] 1 Alternating-current power supply 2 Rectifier circuit (diode bridge) 3 Smoothing capacitor 25 4, 4a, 4b Control circuit 5a, 5b, 5c, 5d Inductor 6a, 6b, 6c, 6d Switching element 7a, 7b, 7c, 7d Diode 8a, 8b, 8c, 8d, 8e Series inductor circuit 30 10 Load 50, 51, 52 Interleaved converter 101a, 101b, 101c Input side switch 102a, 102b, 102c Output side switch Docket No. PMDA-13240-PCT 37 103a, 103b, 103c Inter-inductor switch 501 to 504 First switching converter circuit 601 to 604 Second switching converter circuit 701, 702 Third switching converter circuit 5
权利要求:
Claims (14) [1] 1. An interleaved converter that is configured by connecting in parallel a plurality of switching converter circuits configured by inductors, switching elements, and 5 diodes, that rectifies, with a rectifier circuit, an alternating-current voltage supplied from an alternating current power supply, and that switches, with the switching elements, an output voltage of the rectifier circuit via the inductors to perform one or both of power factor 10 improvement and a boosting operation and to supply electric power to a load, the interleaved converter comprising: an inter-inductor switch that makes it possible to select whether the inductors are connected in series; an input side switch that is connected to a connection 15 point of the inductor and the inter-inductor switch and makes it possible to select whether electric power is supplied from the rectifier circuit to the inductor side; an output side switch that is connected to a connection point of the inductor and the inter-inductor 20 switch and makes it possible to select whether electric power is supplied from the inductor to the diode side; and a control circuit that controls the inter-inductor switch, the input side switch, and the output side switch. 25 [2] 2. The interleaved converter according to claim 1, wherein the control circuit controls the inter-inductor switch, the input side switch, and the output side switch according to electric energy supplied to the load. 30 [3] 3. The interleaved converter according to claim 2, wherein the control circuit includes, as an operation mode of the interleaved converter, a high-load operation mode and a low-load operation mode corresponding to a load power Docket No. PMDA-13240-PCT 39 range; in the high-load operation mode, configures n (n is an integer equal to or larger than 2) first switching converter circuits each with one of the inductors, one of the switching elements, and one of the diodes; and, in the 5 low-load operation mode, configures one series inductor circuit by connecting n pieces of the inductors in series and configures one second switching converter using the series inductor circuit, one of the switching elements, and one of the diodes. 10 [4] 4. The interleaved converter according to claim 3, wherein the control circuit calculates load power on a basis of a load voltage applied to the load and a load current flowing into the load or a voltage of the 15 alternating-current power supply and an input current input from the alternating-current power supply and switches the operation mode according to calculated load power. [5] 5. The interleaved converter according to claim 4, 20 wherein, as a condition for switching the operation mode, the control circuit sets a first load power threshold for shifting the operation mode from the high-load operation mode to the low-load operation mode to a value lower than a second load power threshold for shifting the operation mode 25 from the low-load operation mode to the high-load operation mode. [6] 6. The interleaved converter according to claim 3, wherein the control circuit further includes, as the 30 operation mode of the interleaved converter, an intermediate-load operation mode in which a load power range is lower than a load power range of the high-load operation mode and higher than a load power range of the Docket No. PMDA-13240-PCT 40 low-load operation mode and, in the intermediate load operation mode, configures (n/m) series inductor circuits by connecting m (m is 1 and divisors of n other than n) pieces of the inductors in series and configures (n/m) 5 third switching converter circuits using one of the series inductor circuits, one of the switching elements, and one of the diodes for each of the (n/m) third switching converter circuits. 10 [7] 7. The interleaved converter according to claim 6, wherein the control circuit calculates load power on a basis of a load voltage applied to the load and a load current flowing into the load or a voltage of the alternating-current power supply and an input current input 15 from the alternating-current power supply and switches the operation mode according to calculated load power. [8] 8. The interleaved converter according to claim 7, wherein, as a condition for switching the operation mode, 20 the control circuit sets a first load power threshold for shifting the operation mode from the high-load operation mode to the intermediate-load operation mode to a value lower than a second load power threshold for shifting the operation mode from the intermediate-load operation mode to 25 the high-load operation mode and sets a third load power threshold for shifting the operation mode from the intermediate-load operation mode to the low-load operation mode to a value lower than a fourth load power threshold for shifting the operation mode from the low-load operation 30 mode to the intermediate-load operation mode. [9] 9. The interleaved converter according to claim 3, wherein, in the high-load operation mode, the control Docket No. PMDA-13240-PCT 41 circuit drives n pieces of the switching elements such that electric currents flowing to n pieces of the inductors have a phase difference of (360 0 /n) relative to each other. 5 10. The interleaved converter according to claim 6, wherein, in the high-load operation mode, the control circuit drives n pieces of the switching elements such that electric currents flowing to n pieces of the inductors have a phase difference of (360 0 /n) relative to each other. [10] 10 [11] 11. The interleaved converter according to claim 6, wherein, in the intermediate-load operation mode, the control circuit drives (n/m) pieces of the switching elements configuring the (n/m) third switching converter 15 circuits such that electric currents flowing to (n/m) pieces of the inductors have a phase difference of (360 0 /(n/m)) relative to each other. [12] 12. The interleaved converter according to claim 10, 20 wherein, in the intermediate-load operation mode, the control circuit drives (n/m) pieces of the switching elements configuring the (n/m) third switching converter circuits such that electric currents flowing to (n/m) pieces of the inductors have a phase difference of 25 (360 0 /(n/m)) relative to each other. [13] 13. The interleaved converter according to claim 3, wherein the control circuit switches the operation mode according to operation mode request information input from 30 an outside. [14] 14. The interleaved converter according to claim 6, Docket No. PMDA-13240-PCT 42 wherein the control circuit switches the operation mode according to operation mode request information input from an outside.
类似技术:
公开号 | 公开日 | 专利标题 AU2012368602B2|2015-04-09|Interleaved converter Han et al.2005|A new active clamping zero-voltage switching PWM current-fed half-bridge converter CN102447402B|2016-02-03|With the controller of the ON-OFF control circuit of interval US8531854B2|2013-09-10|Power factor correction converter and power factor correction conversion device US9263960B2|2016-02-16|Power converters for wide input or output voltage range and control methods thereof US8654551B2|2014-02-18|Supply device, and LED lighting equipment using the same WO2013035534A1|2013-03-14|Control device for switching power supply circuit, and heat pump unit CN105052245B|2017-09-01|Led drive circuit US8488350B2|2013-07-16|DC-AC inverters Kim et al.2013|On/off control of boost PFC converters to improve light-load efficiency in paralleled power supply units for servers CN103516196A|2014-01-15|Switching power-supply device TWI536709B|2016-06-01|Power systme and method for providing power US20140009972A1|2014-01-09|Control method for bidirectional DC-DC converters US8441237B2|2013-05-14|Power factor correction | circuit and method therefor EP2608381B1|2019-01-23|AC-DC converter US8437155B2|2013-05-07|Device for power factor correction in three phase power supply and control method thereof EP3503366B1|2020-12-16|Uninterruptible power supply apparatus JP2010172146A|2010-08-05|Switching power supply and power supply control semiconductor integrated circuit CN110707957B|2021-07-06|Current conversion device with overcurrent protection control EP2239835B1|2011-09-07|Converter device and corresponding method JP2006352959A|2006-12-28|Dc-dc converter Mino et al.2010|A front-end converter with high reliability and high efficiency CN109196768B|2021-01-15|AC-DC power converter and method for the same KR20180055266A|2018-05-25|Ac-dc converting apparatus for reducing a current ripple JP6783738B2|2020-11-11|converter
同族专利:
公开号 | 公开日 JP5611474B2|2014-10-22| AU2012368602B2|2015-04-09| CN104094510A|2014-10-08| US9231468B2|2016-01-05| AU2012368602A9|2015-04-09| WO2013114644A1|2013-08-08| EP2811635A1|2014-12-10| US20140347900A1|2014-11-27| JPWO2013114644A1|2015-05-11| EP2811635B1|2019-01-02| AU2012368602A2|2015-01-22| ES2710218T3|2019-04-23| EP2811635A4|2017-04-26| CN104094510B|2017-03-08|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题 JPH04211812A|1990-08-14|1992-08-03|Yokogawa Electric Corp|Active smoothing filter type switching power supply| US6452366B1|2000-02-11|2002-09-17|Champion Microelectronic Corp.|Low power mode and feedback arrangement for a switching power converter| JP2002247839A|2001-02-21|2002-08-30|Matsushita Electric Ind Co Ltd|Dc-dc converter and method of adjusting the same| JP2003348859A|2002-05-30|2003-12-05|Meidensha Corp|Charger for capacitor| US6967854B2|2003-10-30|2005-11-22|Asm Assembly Automation Ltd.|Configurable power supply system for machine components| JP4098299B2|2004-11-18|2008-06-11|本田技研工業株式会社|DC / DC converter| CN2821834Y|2005-02-03|2006-09-27|荣峰电子股份有限公司|Improved switching switch of power factor correcting circuit| JP5515326B2|2009-03-03|2014-06-11|富士ゼロックス株式会社|Power supply apparatus, image forming apparatus, and program| US8248040B2|2009-11-12|2012-08-21|Polar Semiconductor Inc.|Time-limiting mode for an interleaved power factor correction converter| JP5445507B2|2010-06-03|2014-03-19|株式会社デンソー|Power converter| JP2012016164A|2010-06-30|2012-01-19|Fuji Xerox Co Ltd|Power supply unit and image forming device having the same| US8917075B2|2010-11-01|2014-12-23|Anadigics, Inc.|Switched inductor DC-DC converter|KR101462777B1|2013-04-18|2014-11-20|삼성전기주식회사|Power supplying device| CN103887963B|2014-02-26|2018-08-21|常州信息职业技术学院|Critical conduction full load high power factor correcting circuit| DE102015221098A1|2015-10-28|2017-05-04|Dialog SemiconductorLimited|Switching power converter with configurable parallel / series inductor arrangement| JP6947504B2|2016-12-27|2021-10-13|株式会社京三製作所|Power supply unit and control method of power supply unit| KR102043216B1|2017-08-17|2019-11-11|엘지전자 주식회사|Power transforming apparatus, Method for controlling the same and Air conditioner including the power transforming apparatus| CN107425714A|2017-08-31|2017-12-01|湖北工业大学|The forward direction circuit topology and its control method of a kind of multiple-pole switch inductance| US10763668B2|2017-11-01|2020-09-01|Mediatek Inc.|Converter with inductors coupled in series| CN108092512B|2017-12-11|2020-06-09|三峡大学|Multi-working-condition high-gain multi-port DC/DC converter| CN108923678A|2018-06-28|2018-11-30|中国人民解放军空军工程大学|The airborne microsecond pulse plasma flow control power supply of multichannel|
法律状态:
2015-01-22| DA3| Amendments made section 104|Free format text: THE NATURE OF THE AMENDMENT IS AS SHOWN IN THE STATEMENT(S) FILED 17 NOV 2014 | 2015-04-09| SREP| Specification republished| 2015-08-06| FGA| Letters patent sealed or granted (standard patent)|
优先权:
[返回顶部]
申请号 | 申请日 | 专利标题 JP2012017949||2012-01-31|| JP2012-017949||2012-01-31|| PCT/JP2012/067991|WO2013114644A1|2012-01-31|2012-07-13|Interleaved converter| 相关专利
Sulfonates, polymers, resist compositions and patterning process
Washing machine
Washing machine
Device for fixture finishing and tension adjusting of membrane
Structure for Equipping Band in a Plane Cathode Ray Tube
Process for preparation of 7 alpha-carboxyl 9, 11-epoxy steroids and intermediates useful therein an
国家/地区
|