IGBT (Insulated Gate Bipolar Translator) power module heat dissipation structure and control method thereof

Abstract

The invention discloses an IGBT power module heat radiation structure and a control method thereof, and the structure comprises a heat conductor layer, one surface of the heat conductor layer is fixedly provided with a plurality of refrigeration units, and the other surface of the heat conductor layer is fixedly connected with a radiator. The refrigeration unit comprises a thermoelectric cooler, the cold surface of the thermoelectric cooler is connected with the IGBT power module, and the hot surface of the thermoelectric cooler is connected with the heat conductor layer; the thermoelectric cooler is provided with a plurality of independent working areas, and each working area corresponds to one temperature measuring unit; and the plurality of temperature measuring units are connected with a main control unit in the thermoelectric cooler. The thermoelectric cooler is arranged below the IGBT power module to absorb heat released by the IGBT power module, the phase change material is arranged below the thermoelectric cooler, and the heat is transferred to the radiator by the phase change material, so that the heat is brought to the environment, and the IGBT power module not only can ensure the heat dissipation effect, but also can be miniaturized.

Description

Technical Field

[0001] The present invention relates to the technical field of thermoelectric devices, and in particular to an IGBT power module heat dissipation structure and a control method thereof. Background Art

[0002] The IGBT power module is the core unit of the photovoltaic inverter. The heat dissipation of the IGBT power module is crucial. The traditional IGBT power module heat dissipation method usually adopts a cooling fan and a heat sink for heat dissipation. This method has low heat dissipation efficiency and is very prone to overheating, which can damage the IGBT power module. Secondly, the cooling fan occupies a large space. The space occupied by multiple cooling fans makes the photovoltaic inverter equipped with IGBT power modules compact and difficult to design and layout.

[0003] The "A high-power IGBT module air-cooled heat sink taking into account the operating conditions" disclosed in the Chinese patent literature has a publication number of CN109841585B and a publication date of 2021-03-30, including a copper heat dissipation base installed on the back of the copper substrate of the IGBT module, a heat dissipation fin vertically welded on the outer surface of the copper heat dissipation base, and a heat dissipation fan arranged on one side of the heat dissipation fin; a depression is arranged on the outer position of the copper heat dissipation base corresponding to the IGBT chip, or a depression is arranged on the outer position of the copper heat dissipation base corresponding to the diode chip; a copper tube heat exchanger is welded at the depression; the copper tube heat exchanger is composed of a radiator cold liquid inlet pipe, a radiator hot liquid outlet pipe, a heat dissipation cold circulation pump, and a copper tube radiator fin, which is filled with cooling liquid, and is a closed internal circulation liquid heat dissipation system. This technology fully considers the characteristics of inconsistent local heat generation of the IGBT module under different operating conditions, and designs a copper tube heat exchanger system at the part of the IGBT module where the local heat generation is large to achieve uniform heat dissipation of the copper substrate temperature. However, it is still based on the technology of cooling fans, and there is still the problem that the cooling fan occupies a large space and it is difficult to design and layout the IGBT power module compactly while ensuring heat dissipation. At the same time, although the copper substrate can dissipate heat evenly, it still cannot change the low efficiency of cooling fans. Summary of the invention

[0004] The present invention aims to overcome the problems in the prior art of using a cooling fan to dissipate heat for an IGBT power module, such as low heat dissipation efficiency and easy overheating, and the large space occupied by the cooling fan, which makes it difficult to miniaturize the IGBT power module while ensuring the heat dissipation effect. A heat dissipation structure of an IGBT power module and a control method thereof are provided.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: An IGBT power module heat dissipation structure includes a heat conducting body layer. On one side of the heat conducting body layer, a number of refrigeration units are fixed, and on the other side, it is fixedly connected to a radiator. The refrigeration unit includes a thermoelectric cooler. The cold surface of the thermoelectric cooler is connected to the IGBT power module, and the hot surface of the thermoelectric cooler is connected to the heat conducting body layer. The thermoelectric cooler is provided with a number of independent working areas, and each working area corresponds to a temperature measuring unit. A number of temperature measuring units are connected to the main control unit in the thermoelectric cooler.

[0006] In the present invention, by arranging the thermoelectric cooler under the IGBT power module to absorb the heat released by the IGBT power module, and placing a phase change material under the thermoelectric cooler, the phase change material transfers the heat to the radiator, thereby taking the heat out into the environment, enabling the IGBT power module to ensure the heat dissipation effect and be miniaturized. In addition, when the area corresponding to the phase change material on the heat conducting body layer is relatively large, multiple refrigeration units composed of thermoelectric coolers and IGBT power modules can be simultaneously arranged above the phase change material, and multiple refrigeration units share the heat conducting body layer to save the occupied space of the heat dissipation system. When the area corresponding to the phase change material and the area of the refrigeration unit are close, one refrigeration unit can be correspondingly connected to the heat conducting body layer and the radiator for operation. Applying the thermoelectric cooler and the phase change material to the heat dissipation system of the IGBT power module can greatly save the space occupancy ratio of the IGBT power module heat dissipation system. Moreover, the thermoelectric cooler adopts a multi-loop setting with a number of independent working areas, increasing the flexibility of the working areas, and determining the working areas for refrigeration according to specific refrigeration needs, greatly improving the applicability of the thermoelectric cooler.

[0007] Preferably, the heat conducting body layer includes a phase change material and a cavity filled with the phase change material, and a pressure sensor is arranged on the side of the cavity.

[0008] Preferably, the thermoelectric cooler includes an upper substrate and a lower substrate. A number of thermocouples are arranged between the upper substrate and the lower substrate. Flow guiding sheets are arranged on the opposite sides of the upper substrate and the lower substrate, and both ends of the thermocouple are respectively connected to the flow guiding sheet on the upper substrate and the flow guiding sheet on the lower substrate.

[0009] Preferably, the flow guiding sheet on the upper substrate and the flow guiding sheet on the lower substrate are staggered and corresponding, and the thermocouple connects the flow guiding sheet on the upper substrate and the staggered and corresponding flow guiding sheet on the lower substrate to form a loop with a current path.

[0010] Preferably, the thermoelectric cooler includes four independent working areas, and the upper substrate and the lower substrate can be disassembled or assembled according to the division of the working areas. Each working area includes the upper substrate and the lower substrate within the corresponding area, and an independent loop connected by the thermocouple and the flow guiding sheet between the two.

[0011] Preferably, the main control unit receives the detection data of all temperature measurement units, and controls the power-on or power-off of the corresponding independent circuit according to the detection data of the temperature measurement units.

[0012] Preferably, the thickness of the phase change material is greater than the first thickness; the first thickness is the critical thickness when all the refrigeration units operate at full power and the phase change material just becomes liquid.

[0013] A control method for an IGBT power module heat dissipation structure includes: Determining the working area to be refrigerated according to the heat source area during the operation of the IGBT power module; Obtaining the detection data of the temperature measurement unit in the working area to be refrigerated, and powering on or off the independent circuit based on the comparison result with the temperature threshold; After the working area to be refrigerated is powered on for refrigeration, the operating power of the independent circuit is adjusted step by step according to the detection data of the temperature measurement unit collected regularly.

[0014] In the present invention, first, the working area to be refrigerated is determined according to the heat source area during the actual operation of the IGBT power module, and the thermoelectric cooler is controlled in zones, thereby reducing the refrigeration consumption as a whole; and an initial power can be preset when starting to power on for refrigeration, and the working area is refrigerated with the initial power first. After the initial power cannot meet the actual refrigeration demand, the operating power of the independent circuit is increased step by step to increase the refrigeration power, and the adjustment is continuously made until the requirement is finally met. In this case, the refrigeration power of the independent circuit that is more suitable for the current power module operation power can be adjusted, which can not only maintain the temperature stability but also save consumption.

[0015] Preferably, the powering on or off of the independent circuit based on the comparison result with the temperature threshold includes: In the case of not being powered on, when the detection data of the temperature measurement unit in the working area to be refrigerated is greater than or equal to the first temperature threshold, the independent circuit is powered on; In the case of being powered on, when the detection data of the temperature measurement unit in the working area to be refrigerated is less than the second temperature threshold, the independent circuit is powered off; the second temperature threshold is less than the first temperature threshold.

[0016] Preferably, the adjusting the operating power of the independent circuit step by step according to the detection data of the temperature measurement unit collected regularly includes: Collecting the detection data of the temperature measurement unit in the working area to be refrigerated at fixed time intervals. When the detection data is greater than the first temperature threshold, the operating power of the independent circuit is increased by a set power step until the detection data is less than the first temperature threshold or the independent circuit reaches the maximum operating power.

[0017] The present invention has the following beneficial effects: By arranging the thermoelectric cooler under the IGBT power module to absorb the heat released by the IGBT power module, and placing a phase change material under the thermoelectric cooler, the phase change material transfers the heat to the radiator, thereby taking the heat out into the environment, enabling the IGBT power module to ensure heat dissipation and be miniaturized; Applying the thermoelectric cooler and the phase change material to the heat dissipation system of the IGBT power module can greatly save the space occupation ratio of the heat dissipation system of the IGBT power module, save space for the entire photovoltaic inverter or provide space for the placement of other core components; The thermoelectric cooler adopts a multi-loop setting, and the multi-loop design increases the flexibility of the working area and greatly improves the applicability of the thermoelectric cooler. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the heat dissipation structure of the IGBT power module in the present invention.

[0019] Figure 2 It is a top view of the heat dissipation structure of the IGBT power module in the present invention.

[0020] Figure 3 It is a schematic diagram of the structure of the refrigeration unit in the present invention.

[0021] Figure 4 It is a schematic diagram of the loop in the thermoelectric cooler in the present invention.

[0022] Figure 5 It is a flowchart of the control method of the heat dissipation structure of the IGBT power module in the present invention.

[0023] In the figure: 1. IGBT power module; 2. Thermoelectric cooler; 3. Heat conducting body layer; 4. Radiator; 21. Upper substrate; 22. Lower substrate; 23. Thermocouple; 23.1. Positive pole of the first loop; 23.2. Negative pole of the first loop; 23.3. Positive pole of the second loop; 23.4. Negative pole of the second loop; 23.5. Negative pole of the third loop; 23.6. Positive pole of the third loop; 23.7. Negative pole of the fourth loop; 23.8. Positive pole of the fourth loop. Detailed Embodiments

[0024] The following further describes the present invention in conjunction with the drawings and specific embodiments.

[0025] As Figure 1 and Figure 2 shown, a heat dissipation structure of an IGBT power module includes a heat conducting body layer 3, with a plurality of refrigeration units fixed on one side of the heat conducting body layer 3 and a radiator 4 fixedly connected on the other side; The refrigeration unit includes a thermoelectric cooler 2, the cold surface of the thermoelectric cooler 2 is connected to the IGBT power module 1, and the hot surface of the thermoelectric cooler 2 is connected to the heat conducting body layer 3; The thermoelectric cooler 2 is provided with a number of independent working areas, and each working area is corresponding to a temperature measuring unit; the number of temperature measuring units are connected to the main control unit in the thermoelectric cooler 2.

[0026] It should be noted that in the present invention, by arranging the thermoelectric cooler under the IGBT power module to absorb the heat released by the IGBT power module, and placing the phase change material under the thermoelectric cooler, the phase change material transfers the heat to the radiator, thereby taking the heat out to the environment, so that the IGBT power module can not only ensure the heat dissipation effect but also be miniaturized; applying the thermoelectric cooler and the phase change material to the heat dissipation system of the IGBT power module can greatly save the space occupation ratio of the heat dissipation system of the IGBT power module, and the thermoelectric cooler adopts a multi-loop setting with a number of independent working areas, which increases the flexibility of the working areas. Determine the working areas for refrigeration according to specific refrigeration needs, which greatly improves the applicability of the thermoelectric cooler.

[0027] In addition, when the area corresponding to the phase change material in the heat conducting body layer is relatively large, multiple refrigeration units composed of a thermoelectric cooler and an IGBT power module can be simultaneously arranged above the phase change material, so that multiple refrigeration units share the heat conducting body layer to save the occupied space of the heat dissipation system; when the area corresponding to the phase change material is close to the area of the refrigeration unit, one refrigeration unit can be correspondingly connected to the heat conducting body layer and the radiator for operation.

[0028] It is worth noting that the heat dissipation structure of the IGBT power module in the present invention is divided into four parts: the IGBT power module 1, the multi-loop thermoelectric cooler 2, the heat conducting body layer 3 containing the phase change material, and the radiator 4. The thermoelectric cooler under the IGBT power module is a multi-loop thermoelectric cooler. The thermoelectric cooler is divided into four loops, corresponding to four working areas, which do not interfere with each other, and each working area can be adjusted according to requirements; secondly, if a fault occurs in a certain area, it is also convenient to find and repair, which improves the fault detection rate. Under the thermoelectric cooler, the phase change material is used to absorb the heat on the hot surface of the cooler. The lower surface of the heat conducting body layer containing the phase change material is attached to the radiator, which is to transfer the heat of the heat conducting body layer containing the phase change material and ensure a reasonable solid-liquid phase ratio in the heat conducting body layer containing the phase change material, so that the heat conducting body layer containing the phase change material can continuously absorb the heat on the hot surface of the refrigeration chip.

[0029] As a specific embodiment, the heat conducting body layer 3 includes a phase change material and a cavity filled with the phase change material, and a pressure sensor is arranged on the side of the cavity.

[0030] It should be noted that the heat-conducting body layer includes a phase-change material and a cavity for placing the phase-change material. The cavity is made of a rigid material and abuts against the upper and lower surfaces of the heat-conducting body layer. The phase-change material in the heat-conducting body layer is used to absorb the heat generated by the hot surface of the thermoelectric cooler. When the temperature of the hot surface of the thermoelectric cooler is relatively high, it is difficult to ensure that the temperature of the hot surface is within a normal operating temperature range, which easily leads to thermal failure of the thermoelectric cooler and thus damages the thermoelectric cooler. The cavity is made of a rigid material to ensure that the phase-change material does not cause the cavity to deform and separate from the hot surface of the thermoelectric cooler and the radiator when absorbing heat, ensuring that the contact area between the cavity and the upper and lower surfaces of the heat-conducting body layer is sufficient to effectively absorb the heat generated by the hot surface of the thermoelectric cooler and at the same time transfer the absorbed heat to the environment through the radiator in a timely manner.

[0031] Furthermore, the thickness of the phase-change material is greater than the first thickness; the first thickness is the critical thickness at which all refrigeration units operate at full power and the phase-change material just becomes liquid.

[0032] It should be noted that for the heat dissipated by the hot surface of the thermoelectric cooler, the heat-conducting body layer containing the phase-change material below is used for absorption. Whether the IGBT power module is in the full-power state or the half-power state, the heat-conducting body layer can absorb the heat released by the thermoelectric coolers in each working area. Through the phase change and heat absorption of the phase-change material, due to the control of the thickness of the heat-conducting body layer, the phase-change material of the heat-conducting body layer can always exist in two solid / liquid phases, ensuring that the phase-change material can continuously absorb heat. The heat of the heat-conducting body layer is then transferred to the radiator and finally released to the outside to complete the heat dissipation of the entire system.

[0033] It is worth noting that an elastic film is provided on the side of the cavity, and a pressure sensor is provided on the elastic film. The phase-change material absorbs and releases energy through the mutual transformation between its solid state and liquid state. When the phase-change material undergoes a solid-liquid phase change, there is usually a change in volume. Therefore, the solid-liquid ratio of the phase-change material can be effectively judged by collecting the volume information of the phase-change material, and then whether the thermoelectric cooler can continue to operate can be determined according to the solid-liquid ratio of the phase-change material. The elastic film provided on the side of the cavity is used to prevent the volume expansion of the phase-change material when it absorbs heat and becomes liquid from damaging the cavity, resulting in insufficient contact area between the cavity and the upper and lower surfaces of the heat-conducting body layer, and unable to effectively absorb the heat generated by the hot end face of the thermoelectric cooler and transfer the absorbed heat to the environment through the radiator in a timely manner. At the same time, when the phase-change material absorbs heat and becomes liquid, its volume expansion directly generates pressure on the elastic film. At this time, the pressure sensor provided on the elastic film can collect the expanded volume of the elastic film according to the pressure, and thus obtain the change in the volume information of the phase-change material, so as to judge the solid-liquid ratio of the phase-change material, and then determine whether the thermoelectric cooler can continue to operate according to the solid-liquid ratio of the phase-change material.

[0034] The phase change material can be a paraffin-based phase change material. By studying and analyzing the melting point, heat transfer characteristics, and phase change volume expansion rate of paraffin-based solid-liquid phase change materials, the present invention selects a heat transfer working fluid matrix material of paraffin-based solid-liquid phase change with a relatively high volume expansion rate. Paraffin-based phase change materials can meet the performance requirements of the heat transfer working fluid required by the present invention within a wide range. Phase change materials that meet the temperature requirements can be prepared by mixing different components. Moreover, paraffin-based phase change materials have advantages such as a large volume expansion rate, no supercooling phenomenon, no corrosion, and stable chemical properties. However, the obvious problem of paraffin-based phase change materials is their low thermal conductivity. Therefore, it is necessary to further enhance their thermal conductivity.

[0035] Based on the above problem of enhancing thermal conductivity, a compounding agent that shortens the melting time of the phase change material can be added to the phase change material. The added compounding agent can significantly shorten the complete melting time of the binary solid-liquid phase change material. When the compounding agent is added to the binary solid-liquid phase change material, the compounding agent has good compatibility with hexadecane. After compounding, the phase change material can not only adjust its phase change temperature, but also reduce the complete melting time of the phase change material after adding the compounding agent. At the same time, the influence on its phase change volume change rate is very small, and the operation is simple.

[0036] As a specific embodiment, as Figure 3 shown, the thermoelectric cooler 2 includes an upper substrate 21 and a lower substrate 22. A plurality of thermocouples 23 are arranged between the upper substrate 21 and the lower substrate 22; flow guide sheets are arranged on the opposite sides of the upper substrate 21 and the lower substrate 22, and both ends of the thermocouple 23 are respectively connected to the upper substrate flow guide sheet and the lower substrate flow guide sheet.

[0037] The upper substrate flow guide sheet and the lower substrate flow guide sheet are staggered and corresponding, and the thermocouple 23 connects the upper substrate flow guide sheet and the staggered corresponding lower substrate flow guide sheet to form a loop with an electric current path.

[0038] It should be noted that the materials of the upper substrate and the lower substrate can be materials such as ceramics that are electrically insulating and have good thermal conductivity. The material of the flow guide sheet is metal for conducting current; in the independent loop formed by connecting the thermocouple, the upper substrate flow guide sheet, and the lower substrate flow guide sheet in series, two thermocouples are connected to one upper substrate flow guide sheet, each thermocouple is respectively connected to one upper substrate flow guide sheet and one lower substrate flow guide sheet, and each lower substrate flow guide sheet is also connected to two thermocouples. The loop formed by connecting the upper and lower substrates and the thermocouple in the present invention belongs to the existing technology, so it will not be described in detail.

[0039] Furthermore, the thermoelectric cooler includes four independent working areas, and the upper substrate and the lower substrate can be disassembled or assembled according to the division of the working areas; each working area includes the upper substrate and the lower substrate in the corresponding area, and an independent loop connected by the thermocouple and the flow guide sheet between the two.

[0040] The main control unit receives the detection data of all temperature measurement units and controls the power on or off of the corresponding independent circuits according to the detection data of the temperature measurement units.

[0041] It should be noted that on the thermoelectric cooler, there are four working areas with the same size and adjustable power. A temperature measurement unit is set at the outlet of the upper substrate corresponding to each working area. The independent circuits in each working area do not interfere with each other and can independently carry out the work of their corresponding working areas. The main control unit is located in the lower substrate of the thermoelectric cooler. The main control unit on each thermoelectric cooler is connected to four temperature measurement units, corresponding to four independent working areas respectively. The size of each working area remains the same to ensure the balance and consistency of the whole system.

[0042] It is worth noting that both the upper substrate and the lower substrate adopt a detachable structural design along the working area. This modular design not only facilitates the assembly and disassembly of the equipment, but also is convenient for daily maintenance and repair. The lower substrate integrates a main control unit. The main control unit is connected to the thermoelectric cooler and the temperature measurement unit through electrical connection, responsible for receiving the temperature data from the temperature measurement unit and intelligently controlling the power on and off operations of single or multiple independent circuits according to these data. The temperature measurement unit used adopts an NTC thermistor, which has the characteristics of high sensitivity and fast response, can provide accurate temperature monitoring data, ensures that the system can obtain the temperature information of each working area in real time, and realizes accurate and efficient temperature control management.

[0043] Specifically, as Figure 4 shown are the four independent circuits corresponding to dividing the thermoelectric cooler into four working areas. Each dotted box corresponds to a working area and an independent circuit, including the path formed by connecting the corresponding thermocouple, upper substrate current-carrying strip and lower substrate current-carrying strip in series, as well as the circuit positive electrode and circuit negative electrode connected to the outside to access the current.

[0044] In the first circuit, the current flows in from the positive electrode 23.1 of the first circuit, passes through the thermocouple of the first circuit and then flows out from the negative electrode 23.2 of the first circuit; in the second circuit, the current flows in from the positive electrode 23.3 of the second circuit, passes through the thermocouple of the second circuit and then flows out from the negative electrode 23.4 of the second circuit; in the third circuit, the current flows in from the positive electrode 23.6 of the third circuit, passes through the thermocouple of the third circuit and then flows out from the negative electrode 23.5 of the third circuit; in the fourth circuit, the current flows in from the positive electrode 23.8 of the fourth circuit, passes through the thermocouple of the fourth circuit and then flows out from the negative electrode 23.7 of the fourth circuit.

[0045] Figure 4The four independent circuits correspond to four working areas, which do not interfere with each other and can regulate each working area according to requirements. Secondly, if a fault occurs in a certain area, it is also convenient to search for and repair, improving the fault detection rate. Assuming that only one working area needs refrigeration, when the heat source is located in the lower left corner, i.e., the first working area, the first circuit is energized at this time, so that the working area of the first circuit performs refrigeration to cool the heat source, and the other independent circuits are in the non-energized state. When the working area that needs refrigeration changes, such as the third working area in the upper right corner, only the third circuit needs to be energized and the power supply of the first circuit is turned off. Under the condition of ensuring the same power consumption, the heat of the heat source is continuously absorbed to maintain the refrigeration effect.

[0046] When there are multiple working areas that need refrigeration, such as when the IGBT power module is turned on at half power and the heat source area is only half of the full power, located in the first working area and the second working area on the left side of the figure. At this time, only the first circuit and the second circuit need to be energized, and the other two independent circuits are not energized, ensuring the refrigeration effect on the heat sources of the first working area and the second working area, while saving power consumption. If the heat source area is the third working area and the fourth working area on the right side of the figure, then the third circuit and the fourth circuit are energized, and the other two independent circuits are not energized. When the working area that needs refrigeration changes, for example, when it changes from the second working area to the third working area, only the second circuit and the fourth circuit need to be energized at this time, and the other circuits continue to be energized, continuously absorbing the heat of the heat source, and conveniently adjusting the energized circuits to adapt to the change of the heat source position.

[0047] Assume that the IGBT power module is turned on at full power. At this time, all four circuits of the thermoelectric cooler are energized, and the entire range corresponding to the IGBT power module is its heat source area. The heat generated by the IGBT power module is quickly absorbed by the cold surface of the thermoelectric cooler, and the heat released by the hot surface of the thermoelectric cooler is absorbed by the heat-conducting body layer containing the phase-change material below the hot surface. The phase-change material in the heat-conducting body layer absorbs heat and undergoes a phase change. Since the thickness of the heat-conducting body layer is controlled, the phase-change material in the heat-conducting body layer will not all turn into liquid, enabling the heat-conducting body layer to continuously absorb the heat released by the thermoelectric cooler. Finally, the heat absorbed by the heat-conducting body layer can be transferred to the external environment through the radiator. Therefore, the heat generated by the IGBT power module can be transferred to the external environment, solving the problem of difficult heat dissipation of the IGBT power module and improving the reliability of the photovoltaic inverter.

[0048] In this embodiment, the overall working area of the thermoelectric cooler in the IGBT power module cooling structure is divided into multiple small working areas, and a method of zoning control is adopted to achieve efficient and flexible thermal management. Through zoning control and independent loop design, not only can efficient and precise temperature control management of the IGBT power module be realized, but also energy utilization is optimized, the maintenance process is simplified, the overall performance and reliability of the system are greatly improved, and the complex and changeable application requirements are met.

[0049] In addition to providing an IGBT power module cooling structure, the present invention also provides a control method for an IGBT power module cooling structure as shown in Figure 5 which includes: Determine the working area to be cooled according to the heat source area during the operation of the IGBT power module; Obtain the detection data of the temperature measurement unit in the working area to be cooled, and energize or de-energize the independent loop based on the comparison result with the temperature threshold; After the working area to be cooled is energized for refrigeration, adjust the operating power of the independent loop step by step according to the detection data of the temperature measurement unit collected regularly.

[0050] It should be noted that in the present invention, first, the working area to be cooled is determined according to the actual heat source area during the operation of the IGBT power module, and the thermoelectric cooler is controlled in zones, so as to reduce the refrigeration consumption as a whole; and an initial power can be preset when starting to energize for refrigeration, and the working area is cooled with the initial power first. After the initial power cannot meet the actual refrigeration demand, the operating power of the independent loop is increased step by step to increase the refrigeration power, and continuous adjustment is made until the requirements are finally met. In this case, the refrigeration power of the independent loop that is more suitable for the current power module operating power can be adjusted, which can not only maintain the temperature stability but also save consumption.

[0051] The control method of the present invention shows significant advantages at multiple levels, greatly improving the overall performance, energy efficiency and maintenance convenience of the system. First of all, the precise temperature control ability is one of the core advantages of this control method. By real-time monitoring the temperature of each working area, the main control unit can quickly respond to temperature changes to ensure that the temperature of each working area is always maintained within the set range. Especially in a complex environment with multiple heat sources, the system can independently control the corresponding loop for each heat source position and intensity to achieve high-precision local refrigeration. This precise temperature control not only ensures the normal operation of the equipment, but also extends the service life of the equipment and reduces the risk of failures caused by overheating or temperature fluctuations.

[0052] Furthermore, the on / off control of the independent circuits enables the system to automatically cut off power in the working areas where refrigeration is not required, avoiding unnecessary energy consumption. For example, when only some working areas need refrigeration, the system only activates the independent circuits corresponding to these areas, while the other circuits remain closed. This on-demand activation strategy significantly reduces the overall energy consumption and improves the energy utilization efficiency, meeting the requirements of modern energy conservation and environmental protection. In addition, when the initial power cannot meet the refrigeration requirements, the refrigeration power that meets the requirements can be gradually adjusted by gradually increasing the operating power of the independent circuits, so as to meet the refrigeration demand with as low consumption as possible.

[0053] As a specific embodiment, powering on or off the independent circuit based on the comparison result with the temperature threshold includes: in the case of not being powered on, when the detection data of the temperature measurement unit in the working area to be refrigerated is greater than or equal to the first temperature threshold, power on the independent circuit; In the case of being powered on, when the detection data of the temperature measurement unit in the working area to be refrigerated is less than the second temperature threshold, power off the independent circuit; the second temperature threshold is less than the first temperature threshold.

[0054] It should be noted that the normal working temperature of the working area is set between the first temperature threshold and the second temperature threshold. When the detected temperature is greater than the first temperature threshold, the independent circuit needs to be powered on to start refrigerating and cooling down. During the cooling process, if the temperature of the working area drops below the second temperature threshold, it means that the temperature of the working area is relatively low, and refrigeration can be stopped until the temperature of the working area rises above the first temperature threshold again to start a new round of refrigeration.

[0055] Furthermore, gradually adjusting the operating power of the independent circuit according to the detection data of the temperature measurement unit collected at regular intervals includes: collecting the detection data of the temperature measurement unit in the working area to be refrigerated at fixed intervals. When the detection data is greater than the first temperature threshold, increase the operating power of the independent circuit by a set power step until the detection data is less than the first temperature threshold or the independent circuit reaches the maximum operating power.

[0056] It should be noted that when the independent circuit in the working area is first powered on, the independent circuit starts to work with the initial power, and the initial power is a preset power value less than the maximum operating power. First, refrigeration is carried out with a lower power. If the refrigeration demand can already be met, there is no need to increase the power and consume more electrical energy; if the refrigeration demand cannot be met, the power is gradually increased according to the power step, and the temperature data in the working area is continuously collected at fixed intervals to determine whether to continue increasing the operating power or maintain the current operating power for refrigeration.

[0057] Specifically, in the embodiments of the present invention, first, the working area to be cooled is determined according to the heat source area during the operation of the IGBT power module; the detection data of the temperature measurement unit in the working area to be cooled is obtained. If the detection data is less than the first temperature threshold, it indicates that the current working area does not need to be cooled yet, and the temperature detection data is collected again after a fixed time interval; when the detection data is greater than or equal to the first temperature threshold, it indicates that the temperature is too high and cooling is required. At this time, the independent circuit of the working area to be cooled is powered on, and cooling is carried out according to the initial power.

[0058] After power-on cooling, the detection data of the temperature is collected at a fixed time interval, and it is judged whether the temperature has dropped compared with the data collected in the previous time. If the temperature drops, it indicates that the operating power of the independent circuit meets the cooling requirement, and cooling is carried out according to the current operating power of the independent circuit. At the same time, the detection data of the temperature is collected at a fixed time interval until the detection data is less than the second temperature threshold and the power is cut off to stop cooling.

[0059] If the temperature does not drop, it indicates that the operating power of the independent circuit still does not meet the cooling requirement. At this time, it is judged whether the independent circuit has reached the maximum operating power. If it has not reached the maximum operating power, the operating power of the independent circuit is increased according to the set power step, and then the detection data of the temperature is collected again at a fixed time interval, and it is judged whether the temperature has dropped compared with the data collected in the previous time. If it drops, the current operating power is maintained for cooling, and the power is cut off after the detection data is less than the second temperature threshold; if it does not drop, the operating power is continuously increased and the same judgment process is repeated until the independent circuit reaches the maximum operating power.

[0060] When the cooling requirement still cannot be met after the independent circuit reaches the maximum operating power, the independent circuits in the adjacent working areas need to be powered on according to their maximum operating powers, and the cooling of the adjacent working areas is used to assist in improving the cooling of the working area to be cooled; at this time, the detection data is collected multiple times at a fixed time interval again: If the detected temperature data drops, it indicates that the cooling requirement can be met, and cooling is carried out according to the current operation plan. At the same time, the detection data of the temperature is collected at a fixed time interval until the temperature is less than the second temperature threshold and the power is cut off to stop cooling; If the detected data does not drop, it indicates that the heat generation speed of the IGBT power module cannot be safely dissipated by the heat dissipation structure under the current conditions, and there is an overheating problem. An alarm needs to be issued, and at the same time, the operation of the IGBT power module is stopped and waiting for the staff to check the specific problem.

[0061] The above embodiments are further elaborations and explanations of the present invention for the convenience of understanding, and are not any limitations to the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An IGBT power module heat dissipation structure, characterized in that: It comprises a heat conductor layer, one side of which is fixed with a plurality of cooling units, and the other side of which is fixedly connected to a heat sink; the cooling unit comprises a thermoelectric cooler, the cold side of the thermoelectric cooler is connected to the IGBT power module, and the hot side of the thermoelectric cooler is connected to the heat conductor layer; The thermoelectric cooler is provided with a plurality of independent working areas, each of which corresponds to a temperature measuring unit; the plurality of temperature measuring units are connected to a main control unit in the thermoelectric cooler.

2. The IGBT power module heat dissipation structure according to claim 1, characterized in that: The heat conductor layer includes a phase change material and a cavity filled with the phase change material, and a pressure sensor is arranged on a side of the cavity.

3. An IGBT power module heat dissipation structure according to claim 1 or 2, characterized in that: The thermoelectric cooler comprises an upper substrate and a lower substrate, wherein a plurality of thermocouples are arranged between the upper substrate and the lower substrate; guide plates are arranged on the opposite sides of the upper substrate and the lower substrate, and the two ends of the thermocouples are respectively connected to the upper substrate guide plate and the lower substrate guide plate.

4. The IGBT power module heat dissipation structure according to claim 3, characterized in that: The upper substrate guide pieces correspond to the lower substrate guide pieces in an alternating manner, and the thermocouples are connected to the upper substrate guide pieces and the alternating corresponding lower substrate guide pieces to form a loop with a current path.

5. An IGBT power module heat dissipation structure according to claim 1, 2 or 4, characterized in that: The thermoelectric cooler includes four independent working areas, and the upper substrate and the lower substrate of the thermoelectric cooler can be disassembled or assembled according to the division of the working areas; each working area includes the upper substrate and the lower substrate in the corresponding area, and an independent circuit between the two connected by a thermocouple and a guide plate.

6. The IGBT power module heat dissipation structure according to claim 5, characterized in that: The main control unit receives the detection data of all the temperature measuring units, and controls the power on or off of the corresponding independent circuits according to the detection data of the temperature measuring units.

7. The IGBT power module heat dissipation structure according to claim 2, characterized in that: The thickness of the phase change material is greater than the first thickness; the first thickness is the critical thickness when all the refrigeration units are running at full power, so that the phase change material just changes to liquid state.

8. A control method for an IGBT power module heat dissipation structure, applicable to the IGBT power module heat dissipation structure according to any one of claims 1 to 7, characterized in that: include: Determine the working area to be cooled according to the heat source area when the IGBT power module is running; Acquire detection data of the temperature measuring unit in the working area to be refrigerated, and power on or off the independent circuit based on the comparison result with the temperature threshold; After the working area to be refrigerated is powered on for refrigeration, the operating power of the independent circuit is adjusted step by step according to the detection data of the temperature measuring unit collected at regular intervals.

9. The control method of the heat dissipation structure of an IGBT power module according to claim 8, characterized in that: The step of energizing or deenergizing an independent circuit based on a comparison result with a temperature threshold comprises: In the case of no power supply, when the temperature measurement unit in the working area to be refrigerated detects data greater than or equal to the first temperature threshold, the independent circuit is powered on; In the case where power is on, when the temperature measurement unit in the working area to be refrigerated detects data less than a second temperature threshold, the independent circuit is powered off; the second temperature threshold is less than the first temperature threshold.

10. The control method of the heat dissipation structure of an IGBT power module according to claim 9, characterized in that: The step of adjusting the operating power of the independent circuit step by step according to the temperature measurement unit detection data collected at regular intervals comprises: The detection data of the temperature measuring unit of the working area to be refrigerated is collected at fixed intervals. When the detection data is greater than a first temperature threshold, the operating power of the independent circuit is increased according to the set power step until the detection data is less than the first temperature threshold or the independent circuit reaches the maximum operating power.

Images