• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to a superconducting rotor (Rotor) for generators and motors, the superconducting field coil 100 for generating a rotating magnetic field by an external drive source; A field coil support part 110 for supporting the field coil 100; A torque tube (120) connected to the field coil support part (110) for transmitting rotational force from the outside to the field coil (100); A rotor inner cylinder (130) surrounding the field coil support (110) including at least the field coil (100); A rotor outer cylinder 140 surrounding the rotor inner cylinder 130; A heat shield plate 160 installed between the rotor inner cylinder 130 and the rotor outer cylinder 140; A refrigerant supply pipe (170) connected to the rotor inner cylinder (130) for supplying a refrigerant into the rotor inner cylinder (130); A refrigerant coagulation device (180) for solidifying the refrigerant supplied in the rotor inner cylinder (130); And an excitation device 190 for exciting the field coil and operating in a quasi-permanent current mode, by cooling the field coil with a solidified refrigerant to superconduct the field coil, thereby increasing reliability in long-term operation and The current density is greatly increased, and the superconducting field coil is operated in a semi-permanent current mode, which has the advantage of having a permanent magnet motor.
    公开号:KR20000060116A
    申请号:KR1019990008191
    申请日:1999-03-12
    公开日:2000-10-16
    发明作者:권영길；류강식；오상수；성기철；윤문수
    申请人:윤문수；한국전기연구소；
    IPC主号:
    专利说明:

    Superconducting Rotor for Generator and Motor}
    BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting rotor (Rotor) for generators and motors, and more particularly to a superconducting rotor for generators and motors, which enables superconducting the field coil of a superconducting motor with a simpler structure.
    In general, a generator consisting of a field coil using a superconducting wire instead of a copper wire is called a superconducting generator, and FIG. 1 illustrates a configuration of a conventional superconducting rotor.
    Conventional superconducting rotor, as shown in Figure 1, the superconducting field coil 10 for generating a rotating magnetic field by an external drive source; A field coil support part 11 for supporting the field coil 10; A torque tube (12) connected to the field coil support part (11) for transmitting rotational force from the outside to the field coil (10); A rotor inner cylinder (13) surrounding at least the field coil support (11) including the field coil (10); A rotor outer cylinder (14) surrounding the rotor inner cylinder (13); A heat shield plate (15) installed between the rotor inner cylinder (13) and the rotor outer cylinder (14); A slip ring 16 and a current inflow line 17 for supplying and exciting current to the field coil 10; And a coolant supply / recovery device 20 for supplying and recovering a coolant for superconducting the field coil 10 into and out of the rotor inner cylinder 13. In addition, the rotor outer cylinder 14 and the rotor inner cylinder 13 is formed of a high vacuum layer 18 for thermal insulation from the outside.
    The coolant supply / recovery device 20 is installed to cool the field coil 10 and maintains the superconducting state. The coolant supply / recovery device 20 is connected to the rotor inner cylinder 13 to supply refrigerant to the inside of the rotor inner cylinder 13. It is configured to include an inner tube 21 and three multiple tubes 22 concentrically installed on the outer side of the inner tube 21 and each having a gas discharge port, and the outer surface of the inner tube 21. Between the multiple pipes 22 is formed of a vacuum layer 23 for thermal insulation.
    Further, when the refrigerant supply / recovery device 20, which is the non-rotating part, is connected to the rotating part side provided with the inner / outer cylinders 13 and 14 of the rotor, the vacuum layer 23 and the non-rotating part side of the rotating part side are provided. In order to keep the vacuum layer 18 continuously in a vacuum state, a FERRO-FLUID MAGNETIC SEALING device 30 is provided.
    In the conventional superconducting rotor of FIG. 1, the cooling mechanism for superconducting the field coil 10 may include liquid helium (4.2 Kelvin, -269 ° C.) or liquid nitrogen (77 Kelvin, -196 ° C.), which is a cryogenic refrigerant. And the inner tube 21 are supplied into the rotor inner cylinder 13, and the superconducting field coil 10 is cooled by the liquid refrigerant to be in a superconducting state. In addition, the refrigerant vaporized while cooling the field coil 10 is discharged through the three multi-pipes 22, and the heat shield plate 15, the torque tube 12, And the current inflow line 17 and the like generated while supplying current to the field coil 10 are cooled.
    1, the cryogenic refrigerant is continuously supplied to the inner rotor tube 13 to superconduct the field coil 10, and the vaporized refrigerant evaporated from the refrigerant is discharged through the multi-pipe 22. . At the same time, when the current continues to be energized through the slip ring 16 and the current inflow line 17 from an external power source, the field coil 10 is excited to generate a strong magnetic field, and the strong field of the field coil 10 Rotation force is transmitted through the torque tube 12 by the field generation, and generates a current in the armature by the generated magnetic field, or vice versa to generate a rotation force by applying a current to the armature.
    The superconducting generators and motors using the conventional superconducting rotors described above can reduce the loss by more than 50% compared to the conventional phase conducting generators and motors, and can carry a large amount of current through the field coil. It can be more than doubled or the size can be reduced by half at the same capacity, which has the advantage of large capacity and / or miniaturization. Therefore, a superconducting generator using the superconducting rotor of FIG. 1 generally has an economic advantage in comparison with a conventional generator at a large capacity, and a superconducting wire of a metal type having a very low use temperature (liquid helium temperature) is used as a superconducting wire for a field coil. Recently, an oxide superconducting wire having a relatively high use temperature (liquid nitrogen temperature) is used for small and medium capacity generators and industrial motors.
    However, the conventional superconducting rotor as shown in FIG. 1 requires a coolant supply / recovery device 20 having a complex multi-cylindrical structure for superconducting the field coil 10, and a vacuum state of the rotating part and the non-rotating part. Because a device such as FERRO-FLUID MAGNETIC SEALING 30 is necessary to maintain the; Due to the difference in heat shrinkage due to the temperature difference of each cylinder of the multiple pipe 22 of the refrigerant supply / recovery device 20, vibration may be caused during rotation, and the rotation part and the non-rotation part may be connected while maintaining a high vacuum. There is a disadvantage that a problem may occur in the reliability when prolonged operation in the site.
    The present invention was created in order to solve the conventional problems as described above, the object of which is to enable the superconductivity of the field coil without the refrigerant supply / recovery device of a complicated structure, the generator is able to reliably maintain high vacuum at the required part And to provide a superconducting rotor for the motor.
    Another object of the present invention is to provide a superconducting rotor for generators and motors to improve the reliability of long-term operation by enabling the use of solidified nitrogen as a cooling medium of the field coil to cool the field coil for a long time. will be.
    Another object of the present invention is to provide a superconducting rotor for a generator and a motor to operate the superconducting field coil in a semi-permanent current mode.
    1 is a longitudinal sectional view of a conventional superconducting rotor,
    2 is a longitudinal sectional view of a superconducting rotor for a generator and a motor according to the present invention;
    3 is a view of adding the embodiment of the cooling system according to the present invention to the rotor of FIG.
    4 is a view of another embodiment of the cooling system according to the invention to the rotor of FIG.
    ※ Explanation of code for main part of drawing
    100: superconducting field coil 110: field coil support
    120: torque tube 130: rotor inner cylinder
    140: rotor outer cylinder 150: vacuum portion
    160: heat shield 170: refrigerant supply pipe
    180: coagulation supply device 181: heat exchange tube
    182: supply supply pipe 183: heat exchange fin
    190: excitation device 191: current inlet wire connection
    192: permanent current switch 210: liquid nitrogen tank
    220: liquid helium tank 230: helium gas tank
    310: cryogenic freezer 320: cooling stage
    330: heat exchange pipe 335: heat insulation pipe
    340: vacuum container
    350: FERRO-FLUID MAGNETIC SEALING Device
    In order to achieve the above object, a superconducting rotor for a generator and a motor according to the present invention includes: a superconducting field coil for generating a rotating magnetic field by an external driving source; A field coil support for supporting the field coil; A torque tube connected to the field coil support to transfer the rotational force generated by the field coil to the outside; A rotor inner cylinder surrounding the field coil support including at least the field coil; A rotor outer cylinder surrounding the rotor inner cylinder; A heat shield plate installed between the rotor inner cylinder and the rotor outer cylinder; A refrigerant supply pipe connected to the rotor inner cylinder to supply a refrigerant into the rotor inner cylinder; Refrigerant solidification means for solidifying the refrigerant supplied into the rotor inner cylinder; And exciting means for exciting the field coil and operating in a (quasi) permanent current mode.
    According to such a configuration, since the superconducting field coil can be superconducted by cooling the superconducting field coil with a solidified refrigerant at low temperature, the heat transfer between the solidified refrigerant and the field coil becomes heat transfer between the solids, so that the heat transfer is better than that of the conventional liquid refrigerant. In addition, it is possible to increase the energizing current of the field coil due to the coolant solidified to further lower the temperature.
    The refrigerant solidification means may include a heat exchange tube installed inside the rotor inner cylinder; And a refrigerant supply pipe helically installed on an outer surface of the heat exchange tube to circulate a solidification medium capable of solidifying the refrigerant, and a plurality of heat exchange fins protruding circumferentially on the outer surface of the heat exchange tube. It facilitates heat exchange between the condensation and the refrigerant.
    The coagulation medium is used as a medium having a temperature below the freezing point of the refrigerant,
    The refrigerant is liquid nitrogen and the coagulation medium is helium gas.
    The refrigerant coagulation means is connected to the coagulation supply pipe, and a cryogenic freezer for cooling the coagulation medium is added to cool the coagulation medium to be maintained at a constant low temperature even during long time operation.
    The excitation means includes: a current inlet wire connecting portion connected to the field coil so that each of the windings of the field coil is LAB-JOINTING, and a current inlet wire for supplying current to the field coil is detachable; And a permanent current switch connected to the field coil so as to switch the field coil into a permanent current mode, and after the field coil is excited, the permanent current switch is turned off and the current inlet is removed. Operate in permanent current mode.
    The rotor outer cylinder is provided with a vacuum port for maintaining a space between the inner surface of the rotor outer cylinder and the outer surface of the rotor outer cylinder in a vacuum state.
    Hereinafter, a superconducting rotor for a generator and a motor according to a preferred embodiment of the present invention with reference to the accompanying drawings will be described in detail.
    2 is a cross-sectional view showing the configuration of a superconducting rotor according to an embodiment of the present invention.
    2, there is a superconducting field coil 100 that generates a rotating magnetic field by an external drive source, and the field coil 100 is supported by a field coil support 110. The superconducting field coil 100 is preferably composed of an oxide-based superconducting wire. Both ends of the field coil support 110 are integrally connected to a torque tube 120 for transmitting the rotational force generated by the field coil 100 to the outside, and the rotor inner cylinder 130 is The field coil support part 110 including the field coil 100 is installed to surround the rotor outer cylinder 140 and surrounds the rotor inner cylinder 130. Between the rotor inner cylinder 130 and the rotor outer cylinder 140 is formed of a vacuum unit 150 in a high vacuum state to minimize heat intrusion from the outside, radiant heat intrusion from the outside in the vacuum unit 150 The heat shield 160 is provided to block the heat shield 160, and a plurality of super insulation (SUPERINSULATION) (not shown) is installed around the heat shield 160 to minimize heat transfer by radiation. The rotor outer cylinder 140 has a vacuum port 145 is formed to maintain the vacuum state of the vacuum unit 150.
    In addition, a refrigerant supply pipe 170 is connected to the rotor inner cylinder 130 to supply a refrigerant into the rotor inner cylinder 130, and is used to solidify the refrigerant supplied into the rotor inner cylinder 130 to a low temperature. The coolant solidification device 180 is installed, and the coolant solidification device 180 is spirally bonded to the heat exchange tube 181 installed inside the rotor inner cylinder 170 and the outer surface of the heat exchange tube 181. And a solidification supply pipe 182 to circulate a solidification medium capable of solidifying the refrigerant, and a plurality of heat exchange fins 183 protrudes circumferentially on the outer surface of the heat exchange tube 181 to form a solid and It facilitates the heat exchange of the refrigerant. The coagulation medium should be used having a temperature below the freezing point of the refrigerant, preferably the refrigerant uses liquid nitrogen having a freezing point of 63 Kelvin, and the coagulation medium uses a helium gas having a temperature of about 20 to 40 Kelvin. .
    In addition, an exciting device 190 for exciting the field coil 100 and operating in a quasi-permanent current mode is connected to the field coil 100. The excitation device 190 is LAB-JOINTING to a length sufficient to minimize the connection resistance of each winding of the field coil 100, while removing the current inlet wire for supplying current to the field coil (100) It is connected to the current inlet wire connection unit 191 and connected to the field inlet coil 100, so that the superconducting field coil 100 is switched to the semi-permanent current mode so as to be able to It is composed of a permanent current switch 192, the excitation of the field coil 100 after the permanent current switch 192 is turned off (OFF) and removing the current inlet line the field coil 100 is a semi-permanent current To operate in mode.
    Next, the operation of the present invention will be described.
    First, the liquid nitrogen is supplied to the rotor inner cylinder 130 through the refrigerant supply pipe 170 to be filled, and the helium gas having a temperature below the freezing point (63 Kelvin) of the liquid nitrogen is circulated through the refrigerant supply pipe 182. The heat exchange between the helium gas and the liquid nitrogen is performed through the heat exchange tube 181 having the heat exchange fins 183, wherein the liquid nitrogen is solidified. The solidified nitrogen is used as a cooling medium of the superconducting field coil 100. Nitrogen can absorb a lot of heat when it melts because the latent heat during coagulation is large, so that the field coil 100 can be cooled and superconducted for a long time. In addition, by the vacuum unit 150 and the heat shield plate 160 to minimize the heat intrusion into the inside of the rotor inner cylinder 130, and the rotor outer cylinder 140 by installing a vacuum port 145 to the vacuum unit ( Maintain the vacuum of 150). In addition, by connecting the current inlet wire connected to the external power supply to the current inlet wire connection unit 191 to excite the field coil 100, by turning off the permanent current switch 192 and removing the current inlet wire While the intrusion is reduced, the heat generation of the current inlet line is completely eliminated, and the field coil 100 is operated in a quasi-permanent mode with little attenuation of the current by turning off the permanent current switch 192 to generate a stable high magnetic field. Let's do it.
    The solidified nitrogen used as the refrigerant of the field coil 100 can operate for a long time when the solid state is lower than the liquid state because the heat capacity is very large, and directly with the superconducting wire of the field coil 100. The heat transfer efficiency is also very good because conducting heat transfer between the solid and the solid occurs at the contacting portion. In addition, the superconducting wire can further increase the current carrying density when the temperature of the cooling medium used is lowered, thereby further highlighting the advantages of the large-capacity, high-efficiency superconducting generator. Therefore, when using solid nitrogen of 20 to 40 Kelvin as the cooling medium according to the present invention, it is possible to increase the conduction current by three times or more compared to the conventional than using 77 Kelvin of liquid nitrogen as in the prior art.
    As such, after solidifying the liquid nitrogen as the cooling medium, the field coil 100 is excited and the permanent current switch 192 is turned off to operate in the semi-permanent current mode, and the current inlet wire is removed. At this time, the torque tube 120 Induced current is generated in the armature coil by the rotational force transmitted through the. The field coil 100 operates in a quasi-permanent current mode as if it is a permanent magnet type, so it is not necessary to continuously supply current from the outside.
    3, a liquid nitrogen tank 210 connected to the refrigerant supply pipe 170 of FIG. 2 to supply liquid nitrogen is installed, and a liquid helium connected to the refrigerant supply pipe 182 to supply helium gas. The tank 220 and the helium gas tank 230 are provided. Such a cooling system solidifies the liquid nitrogen filled in the rotor inner cylinder 130 using helium gas of an appropriate temperature vaporized from the liquid helium tank 220, and then removes the liquid helium tank 220, and integrates it from the outside. Without the supply of additional refrigerant, the solidified nitrogen can be operated with a permanent magnet rotating field generator or motor until the temperature rises to a certain temperature. It is very advantageous to apply such cooling systems to motors that run intermittently.
    Figure 4 shows that the cryogenic refrigeration apparatus for a long-term continuous operation is installed in the present invention of Figure 2, the cryogenic cooling device, the cryocooler 310 to lower the temperature of the refrigerant to cryogenic; Cooling stage 320 in which the temperature is lowered to the cryogenic temperature in the freezer to heat transfer with the coagulant; A heat exchange pipe 330 wound around the cooling stage 320 a plurality of times and connected to both ends of the condensation supply pipe 182 to exchange heat between the circulating solidification medium and the cooling stage 320; And a vacuum container 340 for blocking heat intrusion from the outside by making the periphery of the heat exchange pipe 330 including the cooling stage 320 in a high vacuum state. Both ends of the heat exchanging pipe 330 exposed to the outside of the vacuum container 340 are made of a heat insulating pipe 335 and are connected to both ends of the coagulation supply pipe 182, and the heat insulating pipe 335 and the coagulation supply pipe The connection portion 182 is firmly connected by the FERRO-FLUID MAGNETIC SEALING device 350 so that the rotor, which is a rotating part, and the cryogenic cooling device, which is a non-rotating part, are connected while maintaining airtightness. Therefore, the coagulation medium circulating through the coagulation supply pipe 182 is cooled by the cryogenic cooling device to maintain and circulate the coagulation medium at a constant low temperature even during long time operation. Such a cooling system is a closed-loop system capable of long-term continuous operation, it is preferable to use a high efficiency Gifford McMahon cryogenic freezer to cool the circulating helium gas, the cooling stage 320 of the heat exchange pipe 330 and the freezer 310 The heat exchange pipe 330 is wound around the cooling stage 320 several times so that sufficient heat exchange occurs at the contact portion of the c). The solidified nitrogen, which is a cooling medium, may have a temperature increase due to thermal intrusion into the inner rotor 130 from the outside, and may vary depending on the operating temperature, but the solidified nitrogen may be present locally in a liquid state. Thus, when the generator or motor is operated continuously for a long time without intermittent operation, when the temperature of the solidified nitrogen rises above a certain temperature, the refrigerator 310 of FIG. 4 is operated to maintain the temperature of the solid nitrogen. . On the other hand, in order to configure the closed circuit cooling system as shown in Figure 4, the FERRO-FLUID MAGNETIC SEALING device 350 is required to maintain the airtight while connecting the rotor and the non-rotating cooling system, the device 350 is Unlike that 30 provided in the conventional superconducting rotor of FIG. 1, the structure is simple and does not have any problem in reliability because it does not need to maintain a high vacuum and merely functions to prevent the helium gas from leaking.
    As described in detail above, according to the superconducting rotor for a generator and the motor according to the present invention, it is possible to superconduct the field coil without the complicated refrigerant supply / recovery device, thereby simplifying the structure and reliably maintaining high vacuum at the required portion. The new concept of using solidified nitrogen as a cooling medium for field coils increases the reliability of long-term operation, greatly increases the field current density of field coils, and makes superconducting field coils semi-permanent current mode. It is effective to have the advantages of the permanent magnet motor by operating as.
    权利要求:
    Claims (9)
    [1" claim-type="Currently amended] A superconducting field coil for generating energy by an external drive source;
    Field coil support means for supporting the field coil;
    A torque tube connected to the field coil support to transfer energy generated by the field coil to the outside;
    A rotor inner cylinder surrounding the field coil support means including the field coil;
    A rotor outer cylinder surrounding the rotor inner cylinder;
    A heat shield plate installed between the rotor inner cylinder and the rotor outer cylinder;
    A refrigerant supply pipe connected to the rotor inner cylinder to supply a refrigerant into the rotor inner cylinder;
    Refrigerant solidification means for solidifying the refrigerant supplied into the rotor inner cylinder; And
    And an exciting means for exciting the field coil and operating in the permanent current mode.
    [2" claim-type="Currently amended] The method of claim 1,
    The refrigerant solidification means,
    A heat exchange tube installed inside the rotor inner cylinder; And
    The superconducting rotor of the generator and the motor, characterized in that consisting of a supply pipe for circulating the solidification is installed on the outer surface of the heat exchange tube to circulate the solidification medium capable of solidifying the refrigerant.
    [3" claim-type="Currently amended] The method of claim 2,
    The superconducting rotor of the generator and motor, characterized in that a plurality of heat exchange fins protruding circumferentially formed on the outer surface of the heat exchange tube.
    [4" claim-type="Currently amended] The method of claim 2,
    The circulating solidification medium is a superconducting rotor of the generator and the motor, characterized in that the material having a temperature below the freezing point of the refrigerant.
    [5" claim-type="Currently amended] The method of claim 2,
    The refrigerant is liquid nitrogen, and the coagulation medium is helium gas.
    [6" claim-type="Currently amended] The method of claim 2,
    The superconducting rotor of the generator and motor, characterized in that it further comprises a cryogenic cooling device for cooling the circulating coagulation medium is installed connected to the coagulation supply pipe.
    [7" claim-type="Currently amended] The method of claim 6,
    The cryogenic cooling device,
    A freezer for lowering the temperature of the coagulant to cryogenic temperature;
    A cooling stage in which the temperature is lowered to a cryogenic temperature in the freezer and heat transfer with the coagulant occurs;
    A heat exchange pipe wound around the cooling stage a plurality of times and connected to both ends of the coagulation supply pipe to exchange heat between the coagulated medium and the cooling unit; And
    The superconducting rotor of the generator and the motor, characterized in that the vacuum container for making a high vacuum around the heat exchange pipe including the cooling unit.
    [8" claim-type="Currently amended] The method of claim 1,
    The woman means,
    A current inlet wire connecting part connected to the field coil so that a current inlet wire for supplying current to the field coil to which each of the windings is lap-joined is detachable; And
    The superconducting rotor of the generator and the motor, characterized in that it is connected to the current inlet wire connection portion configured to a permanent current switch for switching the field coil to the permanent current mode.
    [9" claim-type="Currently amended] The method of claim 1,
    The rotor outer cylinder is a superconducting rotor of the generator and motor, characterized in that the vacuum port for maintaining the space between the inner surface of the rotor outer cylinder and the outer surface of the rotor outer cylinder in a vacuum state is installed.
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    同族专利:
    公开号 | 公开日
    KR100310631B1|2001-10-17|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    1999-03-12|Application filed by 윤문수, 한국전기연구소
    1999-03-12|Priority to KR1019990008191A
    2000-10-16|Publication of KR20000060116A
    2001-10-17|Application granted
    2001-10-17|Publication of KR100310631B1
    优先权:
    申请号 | 申请日 | 专利标题
    KR1019990008191A|KR100310631B1|1999-03-12|1999-03-12|Superconducting Rotor for Generator and Motor|
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