Cooling device and method for current collecting assembly

Abstract

The present invention relates to the technical field of water turbines, and in particular to a cooling device and method for a current collector assembly. The cooling device of the current collector assembly includes a cold source structure and a plurality of thermoelectric generating elements, wherein the thermoelectric generating elements are arranged between the cold source structure and the first side of the carbon brush; a circulating cooling portion, including a heat dissipation structure and a driving pump, wherein the driving pump is electrically connected to the thermoelectric generating element, and a portion of the heat dissipation structure is arranged on the second side of the carbon brush and has a heat dissipation circulation loop. The present invention arranges a thermoelectric generating portion and a circulating cooling portion on a plurality of carbon brushes. As the carbon brushes gradually heat up during operation, a temperature difference is formed between the cold source structure and the carbon brushes, and the thermoelectric generating element generates electricity. The generated electric energy is supplied to the driving pump, so that the heat dissipation structure cools the carbon brushes. A sealed heat dissipation system is used to automatically cool and dissipate heat. While achieving a better heat dissipation effect, dust can also be avoided in the collector ring chamber, effectively solving the problem of poor safety and reliability of the heat dissipation method of the current collector assembly in the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of water turbines, and in particular to a cooling device and method for a current collecting assembly. Background Art

[0002] Collector rings and carbon brushes are devices for dynamic and static contact and energy exchange between generators, and are important components of the excitation system of turbines or pumped storage units. Carbon brushes are devices for transferring electrical energy between the fixed and rotating parts of a generator. They are generally made of pure carbon and graphite with a coagulant, and are usually rectangular and stuck on the brush holder. Due to the friction loss between the carbon brushes and the collector rings and their own electrical loss, the temperature of the carbon brushes and collector rings is extremely high, which can easily cause the carbon brushes and brush holders to burn out, the collector rings to be damaged, and the generator to be forced to shut down.

[0003] At present, the existing collector components generally dissipate heat by setting up a ventilation structure or a fan structure, opening ventilation holes on the carbon brush holder or setting a fan in the collector ring chamber. Since there is carbon powder generated by the friction between the carbon brush and the collector ring in the collector ring chamber, a large amount of dust will be generated when the heat is dissipated in the above manner, which is easy to cause dust accumulation and ignition. The accumulation of carbon powder on electrical components will also affect their insulation performance. Therefore, the heat dissipation method of the existing collector components still has the problem of poor safety and reliability. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of poor safety and reliability of the heat dissipation method of the current collector assembly in the prior art, thereby providing a cooling device and method for the current collector assembly.

[0005] In order to solve the above problems, the present invention provides a cooling device for a collector assembly, the collector assembly includes a collector ring and a plurality of carbon brushes, the plurality of carbon brushes are circumferentially arranged on the outside of the collector ring, the cooling device also includes: a temperature difference power generation part, including a cold source structure and a plurality of temperature difference power generation elements, the temperature difference power generation element is arranged between the cold source structure and the first side of the carbon brush, the cold source structure and the carbon brush are suitable for serving as the low temperature end and the high temperature section of the temperature difference power generation element, respectively, so that the temperature difference power generation element generates electricity; a circulating cooling part, including a heat dissipation structure and a driving pump, the driving pump is electrically connected to the temperature difference power generation element, part of the heat dissipation structure is arranged on the second side of the carbon brush and has a heat dissipation circulation loop, the temperature difference power generation element is suitable for powering the driving pump, and the driving pump drives the heat-conducting cooling medium to flow in the heat dissipation circulation loop to cool the carbon brush.

[0006] Optionally, the heat dissipation control unit includes a controller and a temperature detector, the controller is electrically connected to the drive pump and the temperature detector, and the controller is suitable for controlling the flow rate of the heat-conducting cooling medium according to the temperature of the carbon brush detected by the temperature detector.

[0007] Optionally, the cooling device further includes an adjustable boost / step-up module, and the driving pump is electrically connected to the temperature difference power generation element via the adjustable boost / step-up module.

[0008] Optionally, a heat-conducting insulating layer is provided between the first side of the carbon brush and the temperature difference power generation element, a heat-conducting insulating layer is provided between the second side of the carbon brush and the heat dissipation structure, and / or the heat-conducting cooling medium is liquid metal.

[0009] Optionally, the cold source structure includes an annular cold source tube, the heat dissipation structure includes an annular heat dissipation tube, and the carbon brush is fixed between the cold source tube and the heat dissipation tube.

[0010] Optionally, the cold source pipe is fixedly connected to the heat dissipation pipe via a plurality of fixing parts.

[0011] The present invention also provides a cooling method for a current collector assembly, which uses the above-mentioned cooling device, and the cooling method comprises:

[0012] Step S10: The temperature difference between the cold source structure of the temperature difference power generation unit and the carbon brush is used to make the temperature difference power generation element of the temperature difference power generation unit generate electricity;

[0013] Step S20: The driving pump of the circulating cooling unit is driven by the temperature difference power generation element to drive the heat-conducting cooling medium to flow in the heat dissipation circulation loop of the heat dissipation structure to cool the carbon brushes.

[0014] Optionally, after step S20, the cooling method further includes:

[0015] Step S30: obtaining the temperature of the carbon brush;

[0016] Step S40: controlling the flow rate of the heat-conducting cooling medium according to the temperature of the carbon brush.

[0017] Optionally, step S40 includes:

[0018] Step S41: determining whether the temperature of the carbon brush reaches a preset temperature;

[0019] Step S42: if the temperature of the carbon brush reaches the preset temperature, increase the flow rate of the heat-conducting cooling medium; if the temperature of the carbon brush does not reach the preset temperature, reduce the flow rate of the heat-conducting cooling medium, or keep the flow rate of the heat-conducting cooling medium unchanged.

[0020] Optionally, step S42 includes the following steps: if the temperature of the carbon brush reaches a preset temperature, increasing the output voltage of the adjustable buck-boost module so that the driving pump increases the flow rate of the heat-conducting cooling medium; if the temperature of the carbon brush does not reach the preset temperature, reducing the output voltage of the adjustable buck-boost module so that the driving pump reduces the flow rate of the heat-conducting cooling medium; or, maintaining the output voltage of the adjustable buck-boost module so that the driving pump keeps the flow rate of the heat-conducting cooling medium unchanged.

[0021] The present invention has the following advantages:

[0022] 1. A temperature difference power generation unit and a circulating cooling unit are arranged on a plurality of carbon brushes. As the carbon brushes gradually heat up during operation, a temperature difference is formed between the cold source structure and the carbon brushes, and the temperature difference power generation unit generates electricity. The generated electric energy is supplied to a driving pump, so that the heat dissipation structure cools the carbon brushes. The heat source in the collector assembly is fully utilized to form a self-sustaining power supply. No external power supply is required, and a sealed heat dissipation system is used to automatically cool down and dissipate heat. While achieving a better heat dissipation effect, dust can be avoided in the collector ring room, effectively solving the problem of poor safety and reliability of the heat dissipation method of the collector assembly in the prior art.

[0023] 2. The connection method of several thermoelectric power generation devices is cascade. Through the mixed method of series connection and parallel connection, multiple thermoelectric power generation devices can increase the voltage in series, and can increase the current in parallel, so that several thermoelectric power generation devices can become a stable power source sufficient to drive the drive pump.

[0024] 3. The controller automatically adjusts the flow rate of the heat-conducting cooling medium to keep the carbon brushes within the ideal operating temperature range. While dissipating the heat of the carbon brushes, the collector assembly can also maintain a good working condition.

[0025] 4. In order to accurately determine whether the flow rate of the liquid metal increases, or to more accurately control the heat dissipation temperature, a flow rate sensor is also provided in the heat dissipation circulation loop. The controller detects the flow rate of the liquid metal through the flow rate sensor, thereby controlling the overall heat dissipation process more sensitively and accurately.

[0026] 5. The cold source tube is fixedly connected to the heat dissipation tube through a number of fixings. The cold source tube and the heat dissipation tube can replace part of the structure in the original carbon brush bracket, play a bearing role on the carbon brush, and make the overall structure more streamlined. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A schematic structural diagram of a cooling device of a current collecting assembly according to an embodiment of the present invention is shown;

[0029] Figure 2 Shows Figure 1 An enlarged schematic diagram of a carbon brush of a cooling device of a current collector assembly;

[0030] Figure 3 A schematic diagram showing the steps of a current collector assembly cooling method according to an embodiment of the present invention is shown.

[0031] Description of reference numerals:

[0032] 10. Temperature difference power generation device; 11. Cold source pipe; 12. Cold source box; 21. Driving pump; 22. Adjustable buck-boost module; 23. Heat dissipation pipe; 24. Heat exchange box; 30. Controller; 31. Temperature sensor; 32. Flow rate sensor; 40. Fixing part; 41. Thermal insulation layer; 51. Carbon brush; 52. Collector ring. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] like Figures 1 to 3As shown, the cooling device of the collector assembly of this embodiment includes a collector ring 52 and a plurality of carbon brushes 51, and the plurality of carbon brushes 51 are circumferentially arranged on the outer side of the collector ring 52. The cooling device also includes: a temperature difference power generation unit and a circulation cooling unit. The temperature difference power generation unit includes a cold source structure and a plurality of temperature difference power generation elements 10. The temperature difference power generation element 10 is arranged between the cold source structure and the first side of the carbon brush 51. The cold source structure and the carbon brush 51 are suitable for serving as the low temperature end and the high temperature section of the temperature difference power generation element 10, respectively, so that the temperature difference power generation element 10 generates electricity; the circulation cooling unit includes a heat dissipation structure and a drive pump 21, the drive pump 21 is electrically connected to the temperature difference power generation element 10, a portion of the heat dissipation structure is arranged on the second side of the carbon brush 51 and has a heat dissipation circulation loop, the temperature difference power generation element 10 is suitable for supplying power to the drive pump 21, and the drive pump 21 drives the heat-conducting cooling medium to flow in the heat dissipation circulation loop to cool the carbon brush 51.

[0038] The cooling device of this embodiment is applied, and a temperature difference power generation part and a circulating cooling part are set on a plurality of carbon brushes 51. As the carbon brushes 51 gradually heat up during operation, a temperature difference is formed between the cold source structure and the carbon brushes 51, and the temperature difference power generation element 10 generates electricity. The generated electric energy is supplied to the drive pump 21, so that the heat dissipation structure cools the carbon brushes 51, and the heat source in the collector assembly is fully utilized to form a self-sustaining power supply. No external power supply is required, and a sealed heat dissipation system is used to automatically cool and dissipate heat. While achieving better heat dissipation effect, dust can be avoided in the collector ring room, effectively solving the problem of poor safety and reliability of the heat dissipation method of the collector assembly in the prior art.

[0039] In addition, ventilation and heat dissipation through fan structures and the like will cause carbon powder to float in the collector ring chamber, polluting the indoor hygiene. The cooling device of this embodiment can also maintain the hygiene of the collector ring chamber.

[0040] Specifically, the connection method of several thermoelectric power generation devices 10 is cascade. By mixing series and parallel connection, multiple thermoelectric power generation devices 10 can increase voltage in series and increase current in parallel, so that several thermoelectric power generation devices 10 can become a stable power source sufficient to drive the drive pump 21.

[0041] Preferably, the thermoelectric power generation element 10 is a thermoelectric power generation sheet. The specific material and structure can refer to the existing thermoelectric power generation sheets. The specific number is selected according to the heat generation state of the on-site collector assembly and the required power consumption. Only one thermoelectric power generation sheet can be placed between each carbon brush 51 and the cold source structure, or multiple thermoelectric power generation sheets can be stacked. Among them, the general size of the thermoelectric power generation element 10 is 60*60*5 cubic millimeters, the open circuit voltage is 5V to 18V, and the current is 0.5A to 5A.

[0042] In this embodiment, the heat dissipation control unit includes a controller 30 and a temperature detector. The controller 30 is electrically connected to the drive pump 21 and the temperature detector. The controller 30 is suitable for controlling the flow rate of the heat-conducting cooling medium according to the temperature of the carbon brush 51 detected by the temperature detector. The flow rate of the heat-conducting cooling medium is automatically adjusted by the controller 30, so that the carbon brush 51 is maintained within an ideal operating temperature range. While dissipating the heat of the carbon brush 51, the current collector assembly can also be kept in a good working state.

[0043] Specifically, the temperature detector is a temperature sensor 31. The specific model and detection method of the temperature detector are not limited. It can be a patch type, contact wired, contact wireless, infrared measurement and other detection methods. In order to ensure the safe and stable operation of the collector assembly and avoid overheating damage to the equipment, the hydropower station generally needs to control the temperature of the carbon brush 51 below 80 degrees. Therefore, when the controller 30 detects that the temperature of the carbon brush 51 exceeds 80 degrees, it will speed up the flow rate of the heat-conducting cooling medium to improve the cooling efficiency. It should be noted that Figure 1 The arrangement of the patch temperature sensor 31 is merely illustrated, and is not limited to being arranged on the carbon brush 51 . It is sufficient for the controller 30 to be able to obtain the temperature of the carbon brush 51 .

[0044] Furthermore, there is no limitation on the specific material of the heat-conducting cooling medium, and a commonly used stable medium with strong heat conductivity can be selected, preferably a liquid cooling medium, such as liquid metal, which has a thermal conductivity of up to 39W / (m·K) and can better dissipate heat through circulation. Wherein W is watt, m is meter, and K is Kelvin.

[0045] In this embodiment, the cooling device also includes an adjustable buck-boost module 22, and the drive pump 21 is electrically connected to the temperature difference power generation element 10 through the adjustable buck-boost module 22. The adjustable buck-boost module 22 is introduced, and the input voltage at both ends of the drive pump 21 is adjusted according to the operating temperature of the carbon brush 51 by the controller 30, thereby changing the flow rate of the liquid metal in the heat dissipation structure, and then changing its heat dissipation capacity. It can be understood that if the working stability of the drive pump 21 is not considered, the adjustable buck-boost module 22 may not be set, but in order to enable the controller 30 to effectively control the input voltage of the drive pump 21, the controller 30 needs to have a voltage regulating module itself. At the same time, if in order to reduce the complexity of the overall heat dissipation structure, the temperature difference power generation unit may not be set, and the drive pump 21 and the controller 30 are powered by an external power supply. It should be noted that since the cooling device structure used by the collector components of different sizes is also different, when the input voltage of the drive pump 21 is controlled by the controller 30 according to the temperature, it is necessary to perform a test in advance to establish the corresponding relationship between the input voltage of the drive pump 21 and the carbon brush 51.

[0046] Specifically, since the power generation process of the thermoelectric power generation device 10 may be accompanied by instability and low voltage, an adjustable buck-boost module 22 is provided to increase the output voltage of the thermoelectric power generation device 10 so that the driving pump 21 can maintain a stable working state. The two ends of the thermoelectric power generation device 10 can achieve a temperature difference of 60 to 90 degrees to achieve voltage output. When the system temperature difference is low and the power generation voltage is small, the output voltage can be stabilized with the help of the adjustable buck-boost module 22; the adjustable buck-boost module 22 can use the existing adjustable boost module. Since the flow rate of the liquid metal will change accordingly with the input voltage at both ends of the driving pump 21, the flow rate of the liquid metal can be adjusted accordingly by adjusting the input voltage of the driving pump 21; the driving pump 21 is a normal liquid metal DC electromagnetic driving pump.

[0047] It should be noted that if there is a lot of liquid metal in the heat dissipation circulation loop, the electromagnetic drive pump can be connected in series to increase the driving force of the electromagnetic drive pump.

[0048] In this embodiment, in order to accurately determine whether the flow rate of the liquid metal increases, or to more accurately control the heat dissipation temperature, a flow rate sensor 32 is also provided in the heat dissipation circulation loop. The controller 30 detects the flow rate of the liquid metal through the flow rate sensor 32, thereby more sensitively and accurately controlling the overall heat dissipation process.

[0049] Specifically, there is no limitation on the specific location of the flow velocity sensor 32 , and it only needs to be located on the heat dissipation circulation loop and be able to measure the flow velocity.

[0050] In this embodiment, a thermally conductive insulating layer 41 is provided between the first side of the carbon brush 51 and the temperature difference power generation element 10, and a thermally conductive insulating layer 41 is provided between the second side of the carbon brush 51 and the heat dissipation structure. The thermally conductive cooling medium is liquid metal, which prevents current from being transmitted from the carbon brush 51 to the heat dissipation structure and the temperature difference power generation element 10, thereby ensuring the safety of the structure.

[0051] Specifically, the material of the liquid metal may be gallium-based, indium-based or gallium-indium-tin alloy, etc. High thermal conductivity nanoparticles may also be added to the liquid metal to increase the specific heat capacity of the liquid metal, thereby improving the heat dissipation capacity of the system.

[0052] In this embodiment, the cold source structure includes an annular cold source tube 11, the heat dissipation structure includes an annular heat dissipation tube 23, and the carbon brush 51 is fixed between the cold source tube 11 and the heat dissipation tube 23. The structure is simple and easy to process. The cold source tube 11 is attached to the upper end surface of the carbon brush 51 through the temperature difference power generation element 10, and the heat dissipation tube 23 is attached to the lower end surface of the temperature difference power generation element 10. The annular cold source tube 11 and the heat dissipation tube 23 can better fit with the carbon brush 51, thereby improving the heat conduction and heat dissipation area. Among them, the upper end surface refers to Figure 1 The arrow in the middle points to the "upward" end face, and the lower end face refers to Figure 1It is understood that, as an alternative embodiment, the cold source tube 11 can also be bonded to the lower end surface of the carbon brush 51 through the temperature difference power generation element 10, and the heat dissipation tube 23 can be bonded to the upper end surface of the temperature difference power generation element 10.

[0053] Specifically, the cold source structure also includes a cold source box 12 for storing the cold source, and the inflow end and the outflow end of the cold source pipe 11 are respectively connected to the cold source box 12. The cold source box 12 can be placed in the hood, and the specific size can be determined in combination with the on-site conditions; since the cold source in the cold source pipe 11 cannot automatically complete the cycle, a cold source drive pump is also provided on the cold source circulation loop, and the cold source drive pump is electrically connected to the controller 30, and the controller 30 can simultaneously control the cold source drive pump and the drive pump 21, thereby respectively controlling the flow rate of the cold source and the flow rate of the liquid metal; the specific material of the cold source pipe 11 can use a lightweight material with good thermal conductivity such as aluminum alloy; the cold source in the cold source pipe 11 is the technical cooling water of the power station, which is extracted from the technical water tank of the power station by an external water pump, and continuously updated and flowed, and can be intercommunication with the technical water in the bearing cooling. The cooling water needs to be processed into deionized water to improve the insulation capacity; the gap between the temperature difference power generation element 10 and the cold source pipe 11 is also filled with a high thermal conductivity material to prevent the gap from reducing the thermal conductivity efficiency. Among them, the technology uses cooling water as the cold end, and can also take away part of the heat of the carbon brush 51 through heat conduction, and can also play a role in synchronous heat dissipation. It should be noted that Figure 1 The specific position of the cold source driving pump is not shown in the figure, and it can be set on the cold source circulation loop.

[0054] Specifically, the heat dissipation structure also includes a heat exchange box 24, and the heat dissipation pipe 23 passes through the heat exchange box 24. The heat exchange box 24 can cool the liquid metal in the heat dissipation pipe 23; the heat exchange box 24 can be air-cooled or directly cooled by the water source of the hydropower station itself; there is no limitation on the specific material of the heat dissipation pipe 23, and it can be made of materials such as stainless steel and copper that have good thermal conductivity and will not be corroded by liquid metal; the wall thickness of the heat dissipation pipe 23 and the cold source pipe 11 can be adjusted according to the actual heat dissipation situation, and no strict limitation is made here.

[0055] In this embodiment, the cold source tube 11 is fixedly connected to the heat dissipation tube 23 through a plurality of fixing members 40. The cold source tube 11 and the heat dissipation tube 23 can replace part of the structure in the original carbon brush bracket, play a bearing role for the carbon brush 51, and make the overall structure more streamlined.

[0056] The present invention also provides a cooling method for a current collector assembly, which uses the above-mentioned cooling device, and the cooling method comprises:

[0057] Step S10: The temperature difference between the cold source structure of the temperature difference power generation unit and the carbon brush is used to make the temperature difference power generation element 10 of the temperature difference power generation unit generate electricity;

[0058] Step S20 : ​​The driving pump of the circulating cooling unit is driven by the temperature difference power generation element 10 to drive the heat-conducting cooling medium to flow in the heat dissipation circulation loop of the heat dissipation structure to cool the carbon brush 51 .

[0059] Making full use of the heat source and heat flow on site not only reduces the temperature of the heat source, but also maintains a suitable temperature difference between the high and low ends. No external power supply or external fan is required, reducing the consumption of electricity and the economic investment in the fan.

[0060] In this embodiment, after step S20, the cooling method further includes:

[0061] Step S30: obtaining the temperature of the carbon brush 51;

[0062] Step S40 : controlling the flow rate of the heat-conducting cooling medium according to the temperature of the carbon brush 51 .

[0063] The temperature of the carbon brush 51 and the flow rate of the heat-conducting cooling medium are accurately detected, so that the heat dissipation temperature control is more accurate and effective.

[0064] In this embodiment, step S40 includes:

[0065] Step S41: determining whether the temperature of the carbon brush 51 reaches a preset temperature;

[0066] Step S42: if the temperature of the carbon brush 51 reaches the preset temperature, increase the flow rate of the heat-conducting cooling medium; if the temperature of the carbon brush 51 does not reach the preset temperature, reduce the flow rate of the heat-conducting cooling medium, or keep the flow rate of the heat-conducting cooling medium unchanged.

[0067] The temperature of the carbon brush 51 is maintained at about 80 degrees, which increases the service life of the equipment, reduces the sparking of the carbon brush 51, the wear of the collector ring 52, and the short circuit of the excitation system, and avoids the shutdown of the unit and the impact on the power generation efficiency of the power station.

[0068] In this embodiment, step S42 includes the following steps:

[0069] If the temperature of the carbon brush 51 reaches the preset temperature, the output voltage of the adjustable buck-boost module 22 is increased so that the driving pump 21 increases the flow rate of the heat-conducting cooling medium. If the temperature of the carbon brush 51 does not reach the preset temperature, the output voltage of the adjustable buck-boost module 22 is reduced so that the driving pump 21 reduces the flow rate of the heat-conducting cooling medium. Alternatively, the output voltage of the adjustable buck-boost module 22 is maintained so that the driving pump 21 keeps the flow rate of the heat-conducting cooling medium unchanged.

[0070] The adjustable step-up / step-down module 22 is used to adjust the input voltage at both ends of the electromagnetic pump according to the operating temperature of the carbon brush 51, thereby changing the flow rate of the liquid metal in the pipeline and changing the heat dissipation capacity of the system.

[0071] Specifically, the adjustable buck-boost module 22 in the cooling device can be replaced with an adjustable buck-boost module composed of a DC-AC module, a small transformer and an AC-DC module. Based on the average temperature of the carbon brush 51 and the transformer turns ratio as sample data, a relationship model is established using machine learning to establish a corresponding relationship between the temperature of the carbon brush 51 and the input voltage of the driving pump 21. The input voltage of the driving pump 21 is directly predicted based on the temperature of the carbon brush 51, and automatic control of the cooling system is achieved through a programmable logic controller.

[0072] The cooling principle of the cooling device of this embodiment is described below:

[0073] The temperature difference power generation element 10 generates electricity through the temperature difference formed by the carbon brush 51 and the cold source tube 11 and supplies energy to the controller 30. The controller 30 determines whether to increase or decrease the pressure according to the temperature measured by the temperature sensor 31, and then issues instructions to the adjustable buck-boost module 22. The adjustable buck-boost module 22 outputs the changed voltage, thereby changing the voltage at both ends of the driving pump corresponding to the conventional fluid or the electromagnetic pump corresponding to the liquid metal, thereby changing the flow rate and cooling capacity. The flow rate sensor 32 can be used as feedback to the controller to realize a closed loop.

[0074] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0075] 1. A temperature difference power generation unit and a circulating cooling unit are set on a plurality of carbon brushes 51. As the carbon brushes 51 are gradually heated up during operation, a temperature difference is formed between the cold source structure and the carbon brushes 51, and the temperature difference power generation unit 10 generates electricity. The generated electric energy is supplied to the driving pump 21, so that the heat dissipation structure cools the carbon brushes 51. The heat source in the collector assembly is fully utilized to form a self-sustaining power supply. No external power supply is required. A sealed heat dissipation system is used to automatically cool down and dissipate heat. While having a better heat dissipation effect, dust can also be avoided in the collector ring room.

[0076] 2. Introduce an adjustable step-up / step-down module 22, utilize the characteristics of liquid metal, and adjust the input voltage at both ends of the driving pump 21 through the controller 30 according to the operating temperature of the carbon brush 51, thereby changing the flow rate of the liquid metal in the heat dissipation structure, and then changing its heat dissipation capacity.

[0077] 3. Liquid metal cooling can avoid carbon ink dust caused by external fans, etc., and the noise is extremely low. The entire circulation system is sealed. Liquid metal has high thermal conductivity and is not prone to leakage. At the same time, liquid metal is not easy to react chemically with oxygen and water, and can be reused. The later operation and maintenance costs are much lower than water cooling or fan cooling, and the reliability is strong.

[0078] 4. The heat dissipation device in this solution can significantly reduce the temperature of the carbon brush 51, and will also slightly reduce the surface temperature of the collector ring 52, thereby increasing the service life of the equipment, reducing the sparking of the carbon brush 51, the wear of the collector ring 52, and the short circuit of the excitation system, thereby avoiding the shutdown of the unit and affecting the power generation efficiency of the power station.

[0079] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A cooling device for a current collecting assembly, the current collecting assembly comprising a collector ring (52) and a plurality of carbon brushes (51), wherein the plurality of carbon brushes (51) are circumferentially arranged outside the collector ring (52), characterized in that: The cooling device also includes: A temperature difference power generation unit comprises a cold source structure and a plurality of temperature difference power generation elements (10), wherein the cold source structure comprises a cold source tube (11), and the temperature difference power generation element (10) is arranged between the cold source structure and a first side of the carbon brush (51), and the cold source structure and the carbon brush (51) are respectively adapted to serve as a low temperature end and a high temperature section of the temperature difference power generation element (10), so that the temperature difference power generation element (10) generates electricity; A circulating cooling unit, comprising a heat dissipation structure and a driving pump (21), the heat dissipation structure comprising a heat dissipation pipe (23), the driving pump (21) being electrically connected to the temperature difference power generation element (10), a portion of the heat dissipation structure being arranged on the second side of the carbon brush (51) and having a heat dissipation circulation loop, the temperature difference power generation element (10) being suitable for supplying power to the driving pump (21), and the driving pump (21) driving a heat-conducting cooling medium to flow in the heat dissipation circulation loop to cool the carbon brush (51); Wherein, the heat-conducting cooling medium is a liquid cooling medium.

2. The cooling device according to claim 1, characterized in that: The cooling device also includes a heat dissipation control unit, which includes a controller (30) and a temperature detector. The controller (30) is electrically connected to the drive pump (21) and the temperature detector. The controller (30) is suitable for controlling the flow rate of the heat-conducting cooling medium according to the temperature of the carbon brush (51) detected by the temperature detector.

3. The cooling device according to claim 1, characterized in that: The cooling device also includes an adjustable boost / step-up module (22), and the driving pump (21) is electrically connected to the temperature difference power generation element (10) via the adjustable boost / step-up module (22).

4. The cooling device according to any one of claims 1 to 3, characterized in that: A heat-conducting insulating layer (41) is provided between the first side of the carbon brush (51) and the temperature difference power generation element (10), and a heat-conducting insulating layer (41) is provided between the second side of the carbon brush (51) and the heat dissipation structure. and / or, The heat-conducting cooling medium is liquid metal.

5. The cooling device according to any one of claims 1 to 3, characterized in that: The cold source structure comprises an annular cold source tube (11), the heat dissipation structure comprises an annular heat dissipation tube (23), and the carbon brush (51) is fixed between the cold source tube (11) and the heat dissipation tube (23).

6. The cooling device according to claim 5, characterized in that: The cold source pipe (11) is fixedly connected to the heat dissipation pipe (23) via a plurality of fixing members (40).

7. A method for cooling a current collector assembly, characterized in that: Using the cooling device according to any one of claims 1 to 6, the cooling method comprises: Step S10: generating electricity through the temperature difference between the cold source structure of the temperature difference power generation unit and the carbon brush by the temperature difference power generation element (10) of the temperature difference power generation unit; Step S20: The driving pump of the circulating cooling unit is driven by the temperature difference power generation element (10), and the driving pump drives the heat-conducting cooling medium to flow in the heat dissipation circulation loop of the heat dissipation structure to cool the carbon brush (51).

8. The cooling method according to claim 7, characterized in that: After step S20, the cooling method further includes: Step S30: obtaining the temperature of the carbon brush (51); Step S40: controlling the flow rate of the heat-conducting cooling medium according to the temperature of the carbon brush (51).

9. The cooling method according to claim 8, characterized in that: The step S40 comprises: Step S41: determining whether the temperature of the carbon brush (51) reaches a preset temperature; Step S42: If the temperature of the carbon brush (51) reaches the preset temperature, the flow rate of the heat-conducting cooling medium is increased; if the temperature of the carbon brush (51) does not reach the preset temperature, the flow rate of the heat-conducting cooling medium is reduced, or the flow rate of the heat-conducting cooling medium is maintained unchanged.

10. The cooling method according to claim 9, characterized in that: The step S42 comprises the following steps: If the temperature of the carbon brush (51) reaches the preset temperature, the output voltage of the adjustable buck-boost module (22) is increased so that the drive pump (21) increases the flow rate of the heat-conducting cooling medium; if the temperature of the carbon brush (51) does not reach the preset temperature, the output voltage of the adjustable buck-boost module (22) is reduced so that the drive pump (21) reduces the flow rate of the heat-conducting cooling medium; or, the output voltage of the adjustable buck-boost module (22) is maintained so that the drive pump (21) maintains the flow rate of the heat-conducting cooling medium unchanged.

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