Converter liquid cooling device

Abstract

A liquid cooling device for a converter comprises a liquid cooling plate and a liquid cooling pipeline, a plurality of power module areas are sequentially arranged on the upper surface of the liquid cooling plate at intervals, the liquid cooling pipeline is a serial pipeline and can achieve absolutely balanced flow of the whole pipeline, and effective cleaning of the pipeline can be achieved through high-pressure water injection; the liquid cooling pipeline passes through the projection areas of the power module areas one by one according to a positive sequence in the flowing direction of a liquid cooling medium, then enters the liquid cooling row, turns round after being discharged from the liquid cooling row, and passes through the projection areas of the power module areas one by one according to a reverse sequence, and the liquid cooling pipeline is of a multi-section curve structure in the projection areas of the power module areas; and the passing according to the positive sequence and the passing according to the negative sequence are staggered, so that reliable temperature equalization of the power module can be realized; furthermore, a two-layer small air conditioner is configured to increase the refrigerating capacity and is ingeniously coupled with the one-layer main liquid cooling system, and the low-temperature efficient heat dissipation function of the heating power module and the function of efficient heat dissipation from the outside of the one-layer main liquid cooling system to the space are achieved.

Description

Technical Field

[0001] This utility model relates to the field of energy storage technology, and in particular to a converter liquid cooling device. Background Technology

[0002] A PCS (Power Conversion System) controls the charging and discharging process of a battery, converting AC to DC power, and can directly supply power to AC loads in the absence of a power grid. A PCS consists of a DC / AC bidirectional converter, a control unit, etc., and the converter includes multiple IGBT modules. With the rapid increase in heat flux density of the electronic components in the IGBT modules, the resulting heat dissipation is also increasing dramatically. Simultaneously, the demand for higher power ratings and miniaturization of IGBT modules has led to an increase in the power density of the PCS, resulting in increasingly prominent heat dissipation problems. To solve the converter heat dissipation problem, improve converter cooling efficiency, ensure the stable and reliable operation of high-power converters, and provide technical support for the further development of converter cooling technology, it is necessary to strengthen IGBT module heat dissipation. Existing IGBT module heat dissipation methods include natural cooling, forced air cooling, and liquid cooling technology.

[0003] 1) Natural air cooling uses air as the heat exchange medium and cools through air convection and radiation. However, due to the low specific heat capacity and density of air, its heat dissipation capacity is not high and cannot meet the heat dissipation requirements of power modules.

[0004] 2) Forced air cooling uses a fan to increase the airflow velocity across the heatsink, thereby achieving efficient cooling. Compared to natural cooling, it greatly improves heat dissipation efficiency. The advantages of forced air cooling are simple structure and low cost, and it can be used for devices with relatively high temperatures. However, once the heat dissipation capacity of forced air cooling reaches a certain limit, it cannot further improve the performance of thermal systems such as inverters, and it is noisy.

[0005] 3) Liquid cooling technology requires the fabrication of a heat dissipation substrate. A liquid medium is circulated within a heat dissipation plate made of aluminum, copper, or similar materials to concentrate heat dissipation for power devices, thereby improving heat dissipation performance. Liquid cooling of converters is an effective method for increasing the power density of power modules. Conventional designs use parallel flow channels, which can dissipate heat from the entire liquid cooling plate or from the surface-mounted power heat points on the liquid cooling plate. However, due to issues with pipe length, power heat dissipation point design, and long-term pipe fouling and blockage, flow deviations can occur in the parallel flow channels. Furthermore, design flaws in flow resistance can lead to uneven heat dissipation in the power modules. Power modules with poor heat dissipation become bottlenecks in the long-term reliability of the converter. Additionally, in cases of partial blockage in the parallel flow channels, the liquid cooling medium will flow through areas with lower flow resistance, preventing the original blockage from being flushed. In contrast, serial flow channels can achieve absolutely balanced flow throughout the pipeline, and high-pressure water injection can effectively clean the liquid cooling pipeline. Therefore, this converter liquid cooling heat dissipation system adopts the serial liquid cooling pipeline method. However, the initial temperature at the water inlet gradually increases as the water passes through heat-generating points such as power modules. Even after passing through each heat-generating point such as power modules, reliable temperature uniformity cannot still be achieved.

[0006] The information disclosed in this background section is included only to enhance the understanding of the context of this disclosure, and therefore may contain information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0007] The technical problem to be solved by this utility model is to provide a converter liquid cooling device to address the above-mentioned shortcomings of the prior art in achieving reliable temperature uniformity.

[0008] The technical solution adopted by this utility model to solve its technical problem is: to construct a converter liquid cooling device, including at least one heat dissipation system, the heat dissipation system including a liquid cooling plate and a liquid cooling pipe disposed inside the liquid cooling plate for circulating liquid cooling medium, the upper surface of the liquid cooling plate is provided with a plurality of power module areas for installing power modules and a cooling radiator area for installing liquid cooling radiators for dissipating heat from the internal environment of the device, the plurality of power module areas are arranged sequentially at intervals;

[0009] The liquid cooling pipeline is a serial pipeline; the liquid cooling pipeline passes through the projection areas of multiple power module regions one by one in the forward sequence along the flow direction of the liquid cooling medium before entering the liquid cooling duct, and after exiting the liquid cooling duct, it turns around and passes through the projection areas of multiple power module regions one by one in the reverse sequence.

[0010] The liquid cooling pipeline has a multi-segment curved structure within the projection area of ​​the power module area, and the pipeline alternates between passing through in the forward sequence and passing through in the reverse sequence.

[0011] Furthermore, in the converter liquid cooling device of this utility model, the upper surface of the liquid cooling plate is also provided with an inductor region for mounting inductor units, and the liquid cooling pipeline enters and passes through the projection regions of the inductor region in reverse order after passing through the projection regions of multiple power module regions.

[0012] Furthermore, in the converter liquid cooling device described in this utility model, the liquid cooling plate is divided into upper and lower layers. The upper layer is configured with a liquid cooling system including the liquid cooling pipeline, and the lower layer is configured with a small air conditioning system. The small air conditioning system is coupled to the upper liquid cooling system through the liquid cooling plate.

[0013] The small air conditioning system is used to achieve low-temperature cooling of the power module area, radiator area, or inductor area when an abnormal temperature occurs in the power module area, radiator area, or inductor area.

[0014] Furthermore, in the converter liquid cooling device described in this utility model, a heating area is also allocated on the upper surface of the liquid cooling plate. The liquid cooling pipeline is connected to the liquid cooling medium inlet terminal before passing through the projection areas of multiple power module areas in the forward sequence. After exiting the inductor area, the liquid cooling pipeline enters the projection area of ​​the heating area nearby, and after exiting the projection area of ​​the heating area, it is connected to the liquid cooling medium outlet terminal.

[0015] The small air conditioning system includes a first air conditioning pipe, a compressor, a second air conditioning pipe, and a throttling expansion valve. The compressor and the throttling expansion valve are mounted on the upper surface of the liquid cooling plate. The outlet and inlet of the first air conditioning pipe pass through the liquid cooling plate from bottom to top and are respectively connected to the compressor and the throttling expansion valve. The outlet and inlet of the second air conditioning pipe pass through the liquid cooling plate from bottom to top and are respectively connected to the throttling expansion valve and the compressor.

[0016] The first air conditioning pipe passes through the projection area of ​​multiple power module regions to act as a simulated evaporator to cool the power module located directly above it; the second air conditioning pipe passes through the projection area of ​​the heating region to act as a simulated condenser to heat the liquid cooling pipe located directly above it.

[0017] Furthermore, in the converter liquid cooling device of this utility model, the liquid cooling pipeline in the projection area of ​​the power module area is two serpentine intersecting pipelines, the liquid cooling pipeline forms a serpentine pipeline in the liquid cooling duct, the liquid cooling pipeline forms a serpentine pipeline in the projection area of ​​the inductor area, and the liquid cooling pipeline forms a serpentine pipeline in the projection area of ​​the heating area.

[0018] The first air conditioning pipe forms a serpentine pipe within the projection area of ​​the multiple power module areas, and the second air conditioning pipe forms a serpentine pipe within the projection area of ​​the heating area.

[0019] Furthermore, in the converter liquid cooling device of this utility model, the plurality of power module regions are evenly spaced along a first horizontal direction, the inductor region and the plurality of power module regions are located on the same side of the radiator region, and the plurality of power module regions as a whole are spaced along a second horizontal direction with the inductor region and the heating region.

[0020] Furthermore, in the converter liquid cooling device of this utility model, power module temperature detection points are respectively arranged on both sides of the power module area to monitor the temperature difference on both sides of the power module. All the power module temperature detection points are arranged at intervals parallel to the first horizontal direction, where the first horizontal direction refers to the arrangement direction of the multiple power module areas.

[0021] Temperature detection points for inductor units are respectively arranged on both sides of the inductor region to monitor the temperature difference between the two sides of the inductor unit. The temperature detection points for inductor units on both sides are arranged at intervals parallel to the first horizontal direction. The inductor unit includes multiple inductors, and multiple inductor temperature detection points are arranged around the inductor below each inductor to monitor the temperature difference between the two sides of the inductor.

[0022] Furthermore, in the converter liquid cooling device described in this utility model, the converter controller is used to analyze the detection results of the power module temperature detection point and the inductor unit temperature detection point:

[0023] If the temperature difference between the two sides of the power module is detected to be greater than the first high temperature threshold, it is considered that the heat generation is too large, and the internal abnormality of the power module is further judged by combining the internal temperature monitoring of the power module.

[0024] If the temperature difference between the two sides of the power module is less than the first low temperature threshold, the internal temperature monitoring of the power module is further assessed. If the internal temperature of the power module does not meet the normal operating conditions, it is determined that the power module is not started. If the internal temperature of the power module meets the normal operating conditions, it is determined that the power module is not properly attached to the liquid cooling plate or that the thermal grease is not properly applied.

[0025] If the temperature difference across the inductor unit is detected to be greater than the second high temperature threshold, the inductor is considered to be heating abnormally. Based on the temperature detection result of the inductor unit itself, it is determined whether a false alarm has occurred. If there is no false alarm, then: based on the current detection of the inductor unit, it is determined whether it is caused by overcurrent, and based on the flow detection, it is determined whether it is caused by leakage due to reduced flow.

[0026] If the temperature difference between the two sides of the inductor unit is less than the second low temperature threshold, the temperature detection result of the inductor unit body will be used to determine whether the problem is with the inductor assembly or the application of thermal paste.

[0027] Furthermore, in the converter liquid cooling device of this utility model, the liquid cooling radiator is vertically erected on the liquid cooling plate and perpendicular to the arrangement direction of the multiple power module areas, and multiple heat dissipation fins perpendicular to the heat dissipation surface are protruding on the heat dissipation surface on both sides of the liquid cooling radiator.

[0028] The liquid cooling pipeline passes through the projection areas of multiple power module regions in a forward sequence and enters the liquid cooling radiator near the first vertical side. It then moves vertically upwards within the liquid cooling radiator to the top of the radiator, and then follows a serpentine path to the bottom of the radiator. Finally, it exits the radiator from the second vertical side.

[0029] Furthermore, in the converter liquid cooling device described in this utility model, columnar temperature sensors are also embedded in the liquid cooling plate in an array to form a two-dimensional temperature gradient cloud map, and the depth of the columnar temperature sensors from the upper surface of the liquid cooling plate does not exceed 1 mm.

[0030] The converter liquid cooling device of this utility model has the following beneficial effects: On the one hand, the liquid cooling pipeline is a serial pipeline, which can achieve an absolutely balanced flow rate of the entire pipeline, and the liquid cooling pipeline can be effectively cleaned by high-pressure water injection; on the other hand, the liquid cooling pipeline passes through the projection areas of multiple power module regions one by one in the forward sequence along the flow direction of the liquid cooling medium before entering the liquid cooling drain. After exiting the liquid cooling drain, it turns around and passes through the projection areas of multiple power module regions one by one in the reverse sequence. Moreover, the liquid cooling pipeline has a multi-segment curved structure in the projection areas of the power module regions, and the forward and reverse sequences are staggered, thus achieving reliable temperature uniformity of the power modules. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] Figure 1 This is a top view of one layer of the liquid cooling system in the heat dissipation system;

[0033] Figure 2 This is a top view of a two-story small air conditioning system for heat dissipation.

[0034] Figure 3 This is a front view of the internal double-layer structure of the heat dissipation system;

[0035] Figure 4 This is a left view of the internal double-layer structure of the heat dissipation system;

[0036] Figure 5 This is a top view of the internal double-layer structure of the heat dissipation system;

[0037] Figure 6 This is a schematic diagram of the extended heat dissipation system in the converter;

[0038] Figure 7 This is a schematic diagram of the heat dissipation circulation principle of a two-story small air conditioning system;

[0039] The following are the labeling elements in the figure:

[0040] 1. Liquid cooling medium inlet terminal;

[0041] 2. Liquid cooling piping;

[0042] 3. Placement hole for liquid cooling pipeline inlet temperature sensor;

[0043] 4. Liquid cooling plate;

[0044] 5. Power module;

[0045] 6. Power module;

[0046] 7. Power module;

[0047] 8. Heat dissipation fins;

[0048] 9. Liquid cooling radiator;

[0049] 10. Metal tubes inside the liquid cooling radiator;

[0050] 11. Temperature sensor on the right side of power module 5;

[0051] 12. Temperature sensor on the left side of power module 5;

[0052] 13. Temperature sensor on the right side of power module 6;

[0053] 14. Temperature sensor on the left side of power module 6;

[0054] 15. Temperature sensor on the right side of power module 7;

[0055] 16. Temperature sensor on the left side of power module 7;

[0056] 17. Inductor unit;

[0057] 18. Temperature sensor on the right side of the inductor unit;

[0058] 19. Temperature sensor on the left side of the inductor unit;

[0059] 20. Liquid cooling medium outlet terminal;

[0060] 21. The first air conditioning duct forms a simulated evaporator area;

[0061] 22. First air conditioning duct;

[0062] 23. Temperature sensor between the throttling expansion valve and the simulated evaporator;

[0063] 24. Simulate the temperature sensor between the evaporator and the compressor;

[0064] 25. The second air conditioning duct forms a simulated condenser area;

[0065] 26. Second air conditioning duct;

[0066] 27. Throttling expansion valve;

[0067] 28. Miniature compressor;

[0068] 29. One layer of liquid cooling plate;

[0069] 30. Metal casing for the inductor unit;

[0070] 31. The connecting pipeline for the throttling expansion valve on the second floor;

[0071] 32. The connecting pipeline for the throttling expansion valve on the second floor;

[0072] 33. The connecting pipes for the miniature compressor leading out from the second layer;

[0073] 34. The connecting pipes for the miniature compressor leading out from the second floor;

[0074] 35. Placement hole for liquid cooling pipeline outlet temperature sensor;

[0075] 36. Two-layer liquid cooling plate;

[0076] 37. Piping of the small air conditioning system on the second floor. Detailed Implementation

[0077] To address the shortcomings of existing liquid cooling technologies in achieving reliable temperature uniformity, this invention provides a converter liquid cooling device. Firstly, the liquid cooling pipeline is a serial pipeline, enabling absolutely balanced flow throughout the entire pipeline. High-pressure water injection is sufficient for effective cleaning of the liquid cooling pipeline. Secondly, the liquid cooling pipeline flows sequentially through the projection areas of multiple power module regions in the forward direction of the liquid cooling medium before entering the liquid cooling outlet. After exiting the outlet, it reverses direction and again passes through the projection areas of multiple power module regions sequentially. Furthermore, the liquid cooling pipeline exhibits a multi-segment curved structure within the projection areas of the power module regions, and the forward and reverse flow is staggered, thus achieving reliable temperature uniformity of the power modules.

[0078] To facilitate understanding of this utility model, a more comprehensive description will be given below with reference to the accompanying drawings. The drawings illustrate typical embodiments of this utility model. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of this utility model more thorough and complete. It should be understood that the embodiments of this utility model and the specific features thereof are detailed descriptions of the technical solutions of this application, and not limitations thereof. Where there is no conflict, the embodiments of this utility model and the technical features thereof can be combined with each other.

[0079] refer to Figure 1-5 The converter liquid cooling device of this utility model includes a heat dissipation system, which includes a liquid cooling plate 4, a liquid cooling radiator 9, and liquid cooling pipes 2. The converter's circuit composition includes power modules and other circuit structures.

[0080] refer to Figure 3-5 The liquid cooling plate 4 is divided into upper and lower layers. The upper liquid cooling plate 29 is located near the power module side, and its upper surface is used to house the power module and other circuit structures. The lower liquid cooling plate 36 is located away from the power module side. The upper liquid cooling plate is equipped with a liquid cooling system including the liquid cooling pipes, such as... Figure 1 As shown. The lower liquid-cooled plate is equipped with a small air conditioning system, such as... Figure 2 As shown. The small air conditioning system on the second floor is coupled to the liquid cooling system on the first floor via liquid cooling plate 4. Of course, the small air conditioning system on the second floor is not mandatory, but it can be a preferred option. The liquid cooling system on the first floor will be introduced first, followed by the small air conditioning system on the second floor.

[0081] refer to Figure 1The liquid cooling system has liquid cooling pipes 2 installed inside the liquid cooling plate 4 (specifically, a liquid cooling plate 29) for circulating the liquid cooling medium. It can be understood that the portion of the liquid cooling pipes 2 outside the liquid cooling plate 4 is a welded metal pipe, while the portion inside the liquid cooling plate 4 is a milled groove. The upper surface of the liquid cooling plate 4 is configured with multiple power module areas, radiator areas, inductor areas, and heating areas. The power module areas are used to install power modules. The radiator areas are used to install liquid cooling radiators 9, whose function is to dissipate heat from the internal environment of the device. The inductor areas are used to install inductor units 17. The heating areas are used to heat the discharged liquid cooling medium, improving heat exchange efficiency.

[0082] The power module regions are arranged sequentially at intervals. According to the flow direction of the liquid cooling medium in the liquid cooling pipeline 2, the order in which the power modules gradually move closer to the liquid cooling row 9 is defined as the forward order, and the order in which the power modules gradually move away from the liquid cooling row 9 is defined as the reverse order.

[0083] In this embodiment, the inductor region and the multiple power module regions are located on the same side of the radiator region. The multiple power module regions, as a whole, are arranged at intervals along a second horizontal direction with the inductor region and the heating region. The multiple power module regions are arranged sequentially and evenly at intervals along a first horizontal direction. In this embodiment, the liquid cooling plate 4 is a rectangular plate placed horizontally. The first horizontal direction can be understood as the left-right direction, and the second horizontal direction as the front-back direction. The multiple power module regions, the inductor region, and the heating region are arranged at intervals from front to back, with the radiator region located on the left side of the liquid cooling plate 4. In this embodiment, the inlet of the liquid cooling pipe 2 is connected to the liquid cooling medium inlet terminal 1, and the outlet is connected to the liquid cooling medium outlet terminal 20. Both the liquid cooling medium inlet terminal 1 and the liquid cooling medium outlet terminal 20 are on the right side of the radiator 4. The liquid cooling medium inlet terminal 1 is near the front of the radiator 4, and the liquid cooling medium outlet terminal 20 is near the rear of the radiator 4. Therefore, the multiple power modules are arranged in ascending order from right to left, and in descending order from left to right.

[0084] In this embodiment, the power module specifically consists of three IGBTs, designated as power module 5, 6, and 7, which are arranged in a straight line with even spacing from right to left. It is understood that the number of power modules is not limited to three, nor is the arrangement limited to a straight line; this embodiment uses a straight line arrangement for the purpose of compact layout.

[0085] In this embodiment, the liquid cooling pipeline is a serial pipeline, thus achieving absolutely balanced flow throughout the entire pipeline. High-pressure water injection is sufficient for effective cleaning of the liquid cooling pipeline. However, the initial temperature at the inlet of liquid cooling pipeline 2 gradually increases after passing through heat-generating points such as power modules 5-7, making reliable temperature uniformity impossible. Therefore, in this embodiment, the liquid cooling pipeline 2 is designed to flow in the forward direction through the projection areas of multiple power module regions (i.e., sequentially through power modules 5, 6, and 7) before entering the liquid cooling radiator 9. After exiting the liquid cooling radiator 9, it reverses direction and again passes through the projection areas of multiple power module regions (i.e., sequentially through power modules 7, 6, and 5). Furthermore, the liquid cooling pipeline 2 exhibits a multi-segment curved structure within the projection areas of the power module regions, and the forward and reverse flow sequences are staggered. It is understood that, unless otherwise specified, the pipelines within the same layer of the liquid cooling plate are on the same plane or at the same height.

[0086] The multi-segment curved structure here mainly emphasizes that the piping in the projection area of ​​the power module region is not a straight pipe, but a curve divided into multiple segments. For example, multiple straight bends also belong to the multi-segment curved structure mentioned in this article, as do irregular bends. Specifically, in this embodiment, the liquid cooling pipe 2 in the projection area of ​​the power module region is a serpentine pipe traveling along the first horizontal direction. That is, the overall trend is still along the first horizontal direction (from right to left before the radiator 9, and from left to right after the radiator 9) passing through the projection area of ​​the power module region, but it does not pass through in a straight line, but repeatedly meanders through, roughly in the form of a serpentine pipe. The serpentine pipe can be in the shape of a sine wave, a rectangular wave, etc., and there are no restrictions on the shape. In this embodiment, the serpentine piping is specifically formed by repeatedly turning and changing direction with straight pipes perpendicular to the direction of travel. For example, a serpentine piping traveling from left to right involves a straight pipe traveling from back to front, turning left (before entering radiator 9) / right (after exiting radiator 9) when approaching the front boundary of the area, then traveling from front to back, turning left / right again when approaching the rear boundary of the area, and so on. This serpentine piping can fully fill the projection area of ​​the power module region and ensure consistency with the overall flow trend of the liquid cooling medium as much as possible. Because in this embodiment, the liquid cooling pipe 2 passes through the projection area of ​​the power module region twice, that is, the pipes of the liquid cooling pipe 2 within the projection area of ​​the power module region are two serpentine intersecting pipes. The term "intersecting" means that one side maintains a fixed distance from the other (the distance may have errors and fluctuations, especially in the turning and changing parts), and they do not intersect. We refer to the pipes that pass through the power module area in the forward sequence as pipe A, and the pipes that pass through the power module area in the reverse sequence as pipe B. It should be noted that the parts of pipe A and pipe B outside the projection area of ​​the power module area generally travel in a straight line along the first horizontal direction. Pipes A and B are kept as far apart as possible. For example, the part of pipe A outside the projection area of ​​the power module area is as close as possible to the front boundary of the power module area, and the part of pipe B outside the projection area of ​​the power module area is as close as possible to the rear boundary of the power module area.

[0087] In addition, it can be understood that the projection area of ​​a certain region on the upper surface of the liquid cooling plate 4 refers to the space inside the liquid cooling plate 4 directly below that certain region, and whose boundary is completely consistent with the shape of that certain region.

[0088] The liquid cooling radiator 9 is connected in series in the main liquid cooling system. Its primary function is to dissipate heat from the internal environment of the converter. Specifically, the liquid cooling pipe 2 forms a serpentine pipe pattern within the liquid cooling radiator 9, such as... Figure 4 As shown in metal tube 10. (Reference) Figure 3-4The liquid cooling radiator 9 is vertically positioned on the left side of the liquid cooling plate 4, perpendicular to the arrangement direction of the multiple power modules 5-7. A fan (not shown) is located on the right side of the liquid cooling radiator 9. Numerous heat dissipation fins 8 are arranged at intervals on the heat dissipation surfaces of the left and right sides of the liquid cooling radiator 9. The heat dissipation fins 8 are perpendicular to the heat dissipation surfaces. Each heat dissipation fin 8 is a sheet-like structure extending vertically, and the heat dissipation fins 8 on the same side are arranged in the front-back direction. Alternatively, each heat dissipation fin 8 can be a sheet-like structure extending in the front-back direction, and the heat dissipation fins 8 on the same side can be arranged vertically. The liquid cooling pipe 2 passes through the projection areas of the multiple power module areas in sequence and enters the liquid cooling radiator 9 near the first vertical edge. It then moves vertically upwards within the liquid cooling radiator 9 to the top position, and then follows a serpentine path from top to bottom to the bottom position within the liquid cooling radiator 9. Finally, it exits the liquid cooling radiator 9 from the second vertical edge. The first vertical edge and the second vertical edge are defined as follows: the first vertical edge refers to the vertical edge that is relatively closer to the power module (front edge), and the second vertical edge refers to the vertical edge that is relatively closer to the inductor module (rear edge).

[0089] Continue to refer to Figure 1 The liquid cooling pipeline 2 connects to the liquid cooling medium inlet terminal 1 before passing through the projection areas of multiple power module regions in a forward sequence, passes through the liquid cooling radiator 9, then passes through the projection areas of multiple power module regions in a reverse sequence, enters and passes through the projection area of ​​the inductor region, exits the inductor region, enters the projection area of ​​the heating zone, and exits the projection area of ​​the heating zone to connect to the liquid cooling medium outlet terminal 20. The heating zone works in conjunction with the small air conditioning system on the second floor to improve heat exchange efficiency by raising the temperature in this area. The placement holes 3 and 35 are used to place sensors to detect the inlet and outlet water temperatures, ensuring that the inlet and outlet water temperatures are within the operating range.

[0090] The spans of the inductor region and the heating region in the left-right direction are approximately the same as the span of the region formed by all the power module regions. The liquid cooling pipe 2 forms a serpentine pipe running from front to back within the projection area of ​​the inductor region. The bridge arm side inductor unit 17 can be integrated or placed independently. Due to the good temperature characteristics of the inductor, in this embodiment, the inductor unit 17 is planned to be three inductors integrated into a metal shell 30, fixed by filling medium, with the inductor heat dissipation surface attached to the liquid cooling plate 4. The liquid cooling pipe 2 also forms a serpentine pipe running from front to back within the projection area of ​​the heating region.

[0091] The principle behind achieving uniform temperature in this embodiment is explained below.

[0092] like Figure 1As shown, the liquid cooling medium enters the liquid cooling pipe 2 through the liquid cooling medium inlet terminal 1, and sequentially passes through power modules 5, 6, and 7, absorbing some heat before entering the liquid cooling radiator 9. A fan on the right side of the liquid cooling radiator 9 exchanges heat with the space. The heat dissipation fins 8 increase the heat exchange efficiency of the liquid cooling medium. The metal pipe 10 is the liquid cooling pipe within the liquid cooling radiator 9, which functions as the evaporator in the air conditioning system. After passing through the liquid cooling radiator 9, the liquid cooling medium passes through the three power modules in reverse order, i.e., through modules 7, 6, and 5, forming an alternating position with the initially counter-clockwise flowing liquid cooling medium, achieving a uniform temperature distribution across the power modules. Let T5, T6, and T7 represent the temperatures on the right side of modules 5, 6, and 7, and Ts5, Ts6, and Ts7 represent the temperatures on the left side of modules 5, 6, and 7. The temperatures of each power module satisfy the following relationship:

[0093]

[0094] Wherein, ΔT1 is the temperature rise of the liquid cooling medium of module 6 caused by the heat generated by module 5, ΔT2 is the temperature rise of the liquid cooling medium of module 7 caused by the heat generated by module 6, ΔT3 is the temperature rise of the liquid cooling medium generated by the heat from the internal environment of the converter module by the liquid cooling busbar, ΔT4 is the temperature rise of the liquid cooling medium of module 6 caused by the heat generated by module 7, and ΔT5 is the temperature rise of the liquid cooling medium of module 5 caused by the heat generated by module 6.

[0095] Among them, ΔT1≈ΔT2≈ΔT4≈ΔT5=ΔT, substituting relationship (1): T5+Ts5=T5+T5+ΔT1+ΔT2+ΔT3+ΔT4+ΔT5=2*T5+ΔT3+ΔT1+ΔT2+ΔT4+ΔT5; T6+Ts6=T5+ΔT1 +T5+ΔT1+ΔT2+ΔT3+ΔT4=2*T5+ΔT3+ΔT1+ΔT1+ΔT2+ΔT4; T7+Ts7=T5+ΔT1+ΔT2+T5+ΔT1+ΔT2+ΔT3=2*T5+ΔT3+ΔT1+ΔT2+ΔT1+ΔT2;

[0096]

[0097] As can be seen, this method can achieve uniform temperature distribution in the power module. After passing through the power module, the liquid cooling medium is connected to the first layer of piping in the inductor area on the bridge arm side. After passing through the inductor on the bridge arm side, it enters the heating area for heat exchange in the second-layer simulated condenser. Finally, it flows out through the liquid cooling medium outlet terminal 20, completing the circulation of the liquid cooling medium in the first layer of piping.

[0098] Furthermore, in this embodiment, power module temperature detection points are respectively configured on the left and right sides of the power module area to monitor the temperature difference between the left and right sides of the power module. All the power module temperature detection points are arranged at intervals parallel to the left and right direction. Figure 1In the diagram, points 11, 12, 13, 14, 15, and 16 are temperature detection points beside the IGBT power module, detecting temperatures T11, T12, T13, T14, T15, and T16 respectively. These can be used to determine the temperature differences between T16 and T15, T14 and T13, and T12 and T11. If the detected temperature difference between the two sides of the power module exceeds the first high-temperature threshold TY1, it is considered that the heat generation is excessive, and the internal temperature monitoring of the power module is further combined to determine the internal abnormality of the power module. If the detected temperature difference between the two sides of the power module is less than the first low-temperature threshold TY0, the internal temperature monitoring of the power module is further assessed. If the internal temperature of the power module does not conform to normal operating conditions (normal operating conditions have a certain temperature and will not be too low), it is determined that the power module has not started. If the internal temperature of the power module conforms to normal operating conditions, it is determined that the power module and the liquid cooling plate are not properly bonded, indicating ineffective module fixation, or that improper application of thermal grease has increased thermal resistance, requiring shutdown and inspection.

[0099] Furthermore, in this embodiment, inductor unit temperature detection points are respectively arranged on the left and right sides of the inductor region to monitor the temperature difference between the left and right sides of the inductor unit. The inductor unit temperature detection points on the left and right sides are arranged at intervals parallel to the left and right direction. For example Figure 1 Points 18 and 19 are temperature detection points on the left and right sides of the inductor unit on the bridge arm side. If the temperature difference between the two sides of the inductor unit is greater than the second high temperature threshold TYL1 (i.e., the temperature difference between T19 and T18 is greater than the threshold TYL1), the inductor is considered to be abnormally overheating. Combined with the temperature detection results of the inductor unit itself, it is determined whether a false alarm has occurred. If no false alarm occurs, then: further, the current detection of the inductor unit is used to determine whether it is caused by overcurrent, and the flow rate detection is used to determine whether it is caused by leakage due to reduced flow. If the temperature difference between the two sides of the inductor unit is less than the second low temperature threshold TYL0, then, combined with the temperature detection results of the inductor unit itself, it is determined whether there is an inductor assembly problem, a silicone grease application problem, etc. In addition, multiple inductor temperature detection points are arranged around the inductor below each inductor in the inductor unit to monitor the temperature difference between the two sides of the inductor. Based on this, the temperature difference between each inductor can be determined, the temperature difference between each phase can be determined, and combined with current and voltage detection, it can be determined whether any abnormal operating conditions have occurred in each phase.

[0100] Next, we will introduce the small air conditioning system.

[0101] The small air conditioning system of this utility model can be freely disassembled or assembled. When the temperature of the power module area, the radiator area, or the inductor area is abnormal, the small air conditioning system can achieve low-temperature cooling of the power module area, the radiator area, or the inductor area.

[0102] refer to Figure 2The small air conditioning system includes a two-layer small air conditioning system piping 37, a miniature compressor 28, and a throttling expansion valve 27. Piping 37 includes a first air conditioning piping 22 and a second air conditioning piping 26 located inside the second-layer liquid cooling plate 36, and piping 31-34 passing through the second-layer liquid cooling plate 36 and the first-layer liquid cooling plate 29. The compressor 28 and the throttling expansion valve 27 are installed on the entire upper surface of the liquid cooling plate 4. The outlet and inlet of the first air conditioning piping 22 pass through the liquid cooling plate 4 from bottom to top and are connected to the compressor 28 and the throttling expansion valve 27 respectively. The outlet and inlet of the second air conditioning piping 26 pass through the liquid cooling plate 4 from bottom to top and are connected to the throttling expansion valve 27 and the compressor 28 respectively. Figure 3 In the diagram, 31 is the connecting pipe for the second-layer throttling expansion valve, connected to the outlet of the throttling expansion valve. 32 is the connecting pipe for the second-layer throttling expansion valve, connected to the inlet of the throttling expansion valve. 33 is the connecting pipe for the second-layer miniature compressor, connected to the outlet of the miniature compressor. 34 is the connecting pipe for the second-layer miniature compressor, connected to the inlet of the miniature compressor.

[0103] The first air conditioning duct 22 passes through the projection area of ​​multiple power module regions to act as a simulated evaporator to cool the power module located directly above it, such as... Figure 2 As shown in region 21. The first air conditioning pipe 22 forms a serpentine pipe in region 21, and the direction of this serpentine pipe is the second horizontal direction (specifically from front to back according to the direction of medium flow). This can ensure that the three power modules 5-7 above achieve the same cooling effect and ensure that the power modules 5-7 have a uniform temperature.

[0104] The second air conditioning pipe 26 passes through the projection area of ​​the heating zone to act as a simulated condenser to heat the liquid cooling pipe located directly above it, such as... Figure 2 As shown in region 25. The second air conditioning duct also forms a serpentine duct within region 25, and the direction of travel of this serpentine duct is also the second horizontal direction (specifically from front to back according to the direction of medium flow).

[0105] refer to Figure 7The heat dissipation circulation direction of the two-layer small air conditioning system is from compressor 28 to the simulated condenser (pipeline of zone 25), through the throttling expansion valve 27, to the simulated evaporator (pipeline of zone 21), and then back to compressor 28. The compressor compresses the low-temperature, low-pressure gas into a high-temperature, high-pressure gaseous state. The condenser exchanges the heat of the high-temperature, high-pressure gaseous medium, turning it into a medium-temperature, high-pressure gaseous state. The throttling expansion valve throttles the medium-temperature, high-pressure gaseous state, turning it into a low-temperature, low-pressure liquid mist. The medium passes through the evaporator, absorbs the heat from the object being cooled, and returns to the compressor as a low-temperature, low-pressure gaseous state. Temperature sensor 23 is installed in the pipeline between the throttling expansion valve and the simulated evaporator, and temperature sensor 24 is installed in the pipeline between the simulated evaporator and the compressor. These temperature sensors work together to control the flow rate of the liquid cooling medium in the pipeline.

[0106] In this embodiment, the two-layer miniature air conditioning system is characterized by fully utilizing the liquid cooling plate's own flow channels to simulate the operation of the evaporator and condenser. It is designed in a stacked configuration with the single-layer liquid cooling system, requiring only the addition of a micro compressor 28 and a throttling expansion valve 27 to achieve the functions of a miniature air conditioning system. When abnormal operation occurs, such as excessively high temperatures in the power module 5-7, inductor unit 17, or space heat dissipation liquid cooling radiator 9, or localized excessively high temperatures, the control core issues a command to start the two-layer miniature air conditioning system. Through an independently circulating miniature air conditioning system, low-temperature cooling is achieved at the power module 5-7, inductor unit 17, and space heat dissipation liquid cooling radiator 9, improving cooling efficiency. Simultaneously, by simulating a condenser, the temperature of the liquid cooling medium in the simulated condenser region 25 of the liquid cooling pipe 2 is raised, i.e., the outlet temperature, achieving a large temperature difference between the outlet and inlet water temperatures. This improves the heat exchange efficiency of the external fan of the single-layer liquid cooling system. Since a complete heat exchange in a single layer includes external heat exchange components, the higher the liquid cooling medium temperature and the greater it exceeds the ambient temperature (i.e., a large temperature gradient), the better the heat exchange effect.

[0107] In this embodiment, the first-layer liquid cooling system is the main system of the converter, which consists of a dry cooler (the name of the liquid cooling unit, which can circulate water in the pipeline through an internal water pump), liquid cooling pipeline, upper liquid cooling plate, liquid cooling radiator, temperature and flow detection system, and a mixed medium of ethylene glycol and water flowing in the liquid cooling pipeline. This system can meet the requirements of most friendly operating conditions. The two-layer miniature air conditioning system consists of a lower-layer liquid-cooled plate, compressor, throttling expansion valve, and refrigerant flowing in the pipes, forming an independent system. It is coupled to the main system on the first floor via the liquid-cooled plate. The piping of the two-layer miniature air conditioning system can simulate the effects of a condenser and evaporator. On the first floor, some piping acts as the object of heat dissipation and a fan cooling device. Specifically, the upper layer of zone 21 and zone 17 are the objects of heat dissipation by the two-layer miniature air conditioning system. The upper layer piping of zone 25 simulates the fan that cools the condenser in zone 25. While a normal air conditioner would have a fan that forces airflow from the condenser into the space, this invention cleverly uses the corresponding piping on the upper layer of zone 25 to simulate the function of a fan, absorbing heat from the condenser in zone 25 and then releasing it into the space through the external dry cooler on the first floor. The two-layer liquid cooling system is independently configured in each converter, assisting the main liquid cooling system on the upper floor in operating under various harsh conditions, such as high-temperature environments like deserts and environments with harsh power grids.

[0108] Preferably, a semi-penetrating cylindrical liquid-cooled radiator with blind holes can also be designed. Numerous cylindrical temperature sensors are embedded in the blind holes, passing through the liquid cooling medium, with a depth of no more than 1 mm from the upper surface of the liquid cooling plate. The sensor array distribution can form an accurate two-dimensional temperature gradient cloud map, showing the combined temperature between the liquid cooling medium and the IGBT mounting liquid cooling plate at each point. Based on the temperature cloud map information, the electronic expansion valve can be adjusted via a control circuit to control the water flow rate, thereby achieving temperature uniformity.

[0109] refer to Figure 6 Once the independent liquid cooling system is designed, each liquid cooling plate can be connected through pipes to achieve series or / and parallel use, which can expand the power density of the converter itself.

[0110] In summary, the most significant benefits of this embodiment are:

[0111] 1. The uniform temperature characteristics of the IGBT power module are achieved through the serpentine interlacing design of the serial liquid cooling pipeline. Moreover, the serial pipeline design allows for the addition of high-pressure water flushing logic to the control logic, which is performed before power-on and after power-off. In this way, dirt can be cleaned through the sewage discharge device in the external circulation.

[0112] 2. This utility model adopts a dual-layer liquid cooling system design. The first-layer liquid cooling system is the main liquid cooling system, using ethylene glycol aqueous solution as the liquid cooling medium, which is highly efficient and low-cost. The second-layer liquid cooling system is an auxiliary liquid cooling system, which, through the design of the liquid cooling pipes on the liquid cooling plate itself, simulates the functions of a condenser and evaporator. This utility model integrates a small phase change refrigeration system into the water cooling system. If the first-layer liquid cooling system cannot meet the temperature uniformity or achieve cooling, the second-layer backup small air conditioner is activated to increase the cooling capacity. Moreover, the second-layer liquid cooling system is cleverly coupled with the first-layer main liquid cooling system through the liquid cooling plate, realizing the low-temperature and efficient heat dissipation function of the heat-generating power module, and raising the outlet water temperature to achieve the function of efficient heat dissipation from the outside of the first-layer main liquid cooling system to the space.

[0113] 3. This utility model, in conjunction with temperature detection at various points, can determine whether the power module and inductor module are incorrectly assembled, resulting in increased thermal resistance. It can also identify some severe operating conditions and make corresponding adjustments.

[0114] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," "front," "back," "up," "down," and similar expressions used in this document are for illustrative purposes only.

[0115] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0116] The terms "first," "second," and other ordinal terms used in this specification are used to describe various constituent elements, but these constituent elements are not limited by these terms. The purpose of using these terms is solely to distinguish one constituent element from others. For example, without departing from the scope of this utility model, a first constituent element may be named a second constituent element, and similarly, a second constituent element may be named a first constituent element. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0117] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0118] Similarly, it should be understood that, in order to simplify this disclosure and aid in understanding one or more of the various aspects of the invention, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the claims, the inventive aspect lies in fewer than all features of the single embodiment disclosed above. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0119] It should be noted that the above embodiments are illustrative of the present invention and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0120] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A converter liquid cooling device, characterized in that, The device comprises at least one heat dissipation system, the heat dissipation system comprises a liquid cooling plate and a liquid cooling pipeline arranged inside the liquid cooling plate for circulating liquid cooling medium, the upper surface of the liquid cooling plate is configured with a plurality of power module areas for mounting power modules and a cold row area for mounting a liquid cooling row for dissipating heat from the internal environment of the device, and the plurality of power module areas are sequentially and spacedly arranged; The liquid cooling pipeline is a serial pipeline; the liquid cooling pipeline sequentially passes through the projection areas of the plurality of power module areas in a forward order and then enters the liquid cooling row in a flow direction of the liquid cooling medium, and after exiting the liquid cooling row, the liquid cooling pipeline turns around and sequentially passes through the projection areas of the plurality of power module areas in a reverse order; The liquid cooling pipeline in the projection areas of the power module areas has a multi-segment curve structure, and the forward order passing and the reverse order passing are staggered.

2. The liquid cooling device for power converter according to claim 1, characterized in that, The upper surface of the liquid cooling plate is further configured with an inductor area for mounting an inductor unit, and the liquid cooling pipeline enters and passes through the projection area of the inductor area after sequentially passing through the projection areas of the plurality of power module areas in a reverse order.

3. The liquid cooling device for power converter according to claim 2, characterized in that, The liquid cooling plate is divided into two layers, the upper layer is configured with a liquid cooling system comprising the liquid cooling pipeline, and the lower layer is configured with a small air conditioning system, and the small air conditioning system is coupled with the liquid cooling system of the upper layer through the liquid cooling plate; The small air conditioning system is used to realize low-temperature refrigeration of the power module area, the cold row area or the inductor area when temperature abnormity occurs in the power module area, the cold row area or the inductor area.

4. The liquid cooling device for power converter according to claim 3, characterized in that, The upper surface of the liquid cooling plate is further configured with a heating area, the liquid cooling pipeline is connected with a liquid cooling medium inlet terminal before sequentially passing through the projection areas of the plurality of power module areas in a forward order, and the liquid cooling pipeline enters the projection area of the heating area after exiting the inductor area, and the liquid cooling pipeline is connected with a liquid cooling medium outlet terminal after exiting the projection area of the heating area; The small air conditioning system comprises a first air conditioning pipeline, a compressor, a second air conditioning pipeline and a throttling expansion valve, the compressor and the throttling expansion valve are mounted on the upper surface of the liquid cooling plate, the outlet and the inlet of the first air conditioning pipeline pass through the liquid cooling plate from bottom to top and are respectively connected with the compressor and the throttling expansion valve, and the outlet and the inlet of the second air conditioning pipeline pass through the liquid cooling plate from bottom to top and are respectively connected with the throttling expansion valve and the compressor; The first air conditioning pipeline passes through the projection areas of the plurality of power module areas to serve as a simulated evaporator for cooling the power modules located directly above the first air conditioning pipeline, and the second air conditioning pipeline passes through the projection area of the heating area to serve as a simulated condenser for heating the liquid cooling pipeline located directly above the second air conditioning pipeline.

5. The liquid cooling device of the converter according to claim 4, wherein the pipeline of the liquid cooling pipeline in the projection areas of the power module areas is two serpentine staggered pipelines, the liquid cooling pipeline forms a serpentine pipeline in the liquid cooling row, the liquid cooling pipeline forms a serpentine pipeline in the projection area of the inductor area, and the liquid cooling pipeline forms a serpentine pipeline in the projection area of the heating area. The first air conditioning pipeline forms a serpentine pipeline in the projection area of the plurality of power module areas, and the second air conditioning pipeline forms a serpentine pipeline in the projection area of the temperature rising area.

6. The liquid cooling device for power converter according to claim 4, characterized in that, The plurality of power module areas are uniformly spaced in a first horizontal direction, and the inductor area and the plurality of power module areas are located on the same side of the cooling area, and the plurality of power module areas as a whole are spaced in a second horizontal direction with the inductor area and the temperature rising area.

7. The liquid cooling device of the converter according to claim 2, characterized in that, The power module temperature detection points are arranged on both sides of the power module area to monitor the temperature difference on both sides of the power module, and all the power module temperature detection points are spaced in parallel to the first horizontal direction, which refers to the arrangement direction of the plurality of power module areas; The inductor unit temperature detection points are arranged on both sides of the inductor area to monitor the temperature difference on both sides of the inductor unit, and the inductor unit temperature detection points on both sides are spaced in parallel to the first horizontal direction; the inductor unit includes a plurality of inductors, and a plurality of inductor temperature detection points are arranged around each inductor below the inductor to monitor the temperature difference on both sides of the inductor.

8. The liquid cooling device for power converter according to claim 7, characterized in that, The controller of the converter is used to analyze the detection results of the power module temperature detection points and the inductor unit temperature detection points: If the temperature difference on both sides of the power module is greater than the first high temperature threshold, it is considered that the heat generation is too large, and the internal abnormality of the power module is further judged in combination with the internal temperature monitoring of the power module; If the temperature difference on both sides of the power module is less than the first low temperature threshold, the internal temperature monitoring of the power module is further judged, if the internal temperature monitoring of the power module detects that the temperature does not conform to the normal working condition, it is judged that the power module is not started; if the internal temperature monitoring of the power module detects that the temperature conforms to the normal working condition, it is judged that the power module is abnormally attached to the liquid cooling plate or the silicone grease is abnormally applied; If the temperature difference on both sides of the inductor unit is greater than the second high temperature threshold, it is considered that the inductor is abnormally heated, and whether a false alarm occurs is judged in combination with the body temperature detection result of the inductor unit, if no false alarm occurs, whether overcurrent causes is judged in combination with the current detection of the inductor unit, and whether liquid leakage is caused by reduced flow is judged in combination with the flow detection; If the temperature difference on both sides of the inductor unit is less than the second low temperature threshold, whether the inductor assembly problem or the silicone grease application problem is judged in combination with the body temperature detection result of the inductor unit.

9. The liquid cooling device for power converter according to claim 1, characterized in that, The liquid cooling area is vertically arranged on the liquid cooling plate and perpendicular to the arrangement direction of the plurality of power module areas, and a plurality of heat dissipation fins perpendicular to the heat dissipation surface are protrudingly arranged on the heat dissipation surface on both sides of the liquid cooling area. The liquid cooling pipeline passes through the projection area of the power module area in sequence, and then enters the position close to the first vertical edge of the liquid cooling row, vertically upward to the position close to the top of the liquid cooling row, then reaches the position close to the bottom of the liquid cooling row in a snake-like manner, and then passes out from the position close to the second vertical edge of the liquid cooling row.

10. The liquid cooling device for power converter according to claim 1, characterized in that, The liquid cooling plate is also arrayed with columnar temperature sensors to form a two-dimensional temperature gradient cloud picture, and the depth of the columnar temperature sensors from the upper surface of the liquid cooling plate is not more than 1 mm.

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