Power module thermal resistance test tool

Abstract

The utility model discloses a power module thermal resistance test tool. The power module thermal resistance test tool comprises a radiator and a thermal block installed on the radiator. The heat block comprises a heat dissipation substrate and a DCB substrate soldered on the heat dissipation substrate, a plurality of protruding parts are arranged on the DCB substrate, and chip resistors are fixed on the protruding parts in a soldering mode; the radiator is provided with a plurality of temperature measuring elements which are in contact with the radiating substrate; and performing a simulation test on the actual working condition temperature of the power chip to test whether the heat dissipation effect in actual operation can meet the working condition requirement or not.

Description

Technical Field

[0001] The utility model relates to the technical field of thermal resistance testing of power chips, in particular to a thermal resistance testing tool for a power module. Background Art

[0002] According to the different voltage levels in the mine, 1140V and 3300V frequency conversion equipment has been widely used. The temperature of the power module used in the frequency conversion equipment is difficult to be reliably monitored during long-term operation, because the power module works in a high-voltage environment. If the temperature measuring element directly measures the internal temperature of the power module, the insulation of the temperature measuring element cannot be guaranteed. Therefore, before integrating the power module into the frequency conversion equipment, simulation is performed for the actual application scenario to determine whether the radiator can form a good heat dissipation for the current power module. If the radiator can meet the heat dissipation of the power module, the normal operation of the power module can be guaranteed even if the temperature monitoring cannot be accurately obtained in the actual application; if the radiator cannot meet the heat dissipation of the power module, the heat dissipation method of the radiator needs to be improved to ensure that it can run well after being assembled into the frequency conversion equipment.

[0003] Before assembling the power module, a thermal resistance test is carried out to determine the actual heat dissipation capacity of the heat sink for the power module. However, it is difficult for the power chip to reach the operating temperature during simulation, so the design of tooling is considered to simulate the actual working conditions. Utility Model Content

[0004] 1. Technical issues

[0005] The utility model aims to provide a power module thermal resistance test tool to simulate the actual operating temperature of the power chip to test whether the heat dissipation effect in actual operation can meet the operating requirements.

[0006] (II) Technical solution

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] A thermal resistance test tool for a power module comprises a heat sink and a heat block mounted on the heat sink; the heat block comprises a heat sink substrate and a DCB substrate soldered on the heat sink substrate, the DCB substrate is provided with a plurality of protrusions, and chip resistors are soldered and fixed on the protrusions; a plurality of temperature measuring elements in contact with the heat sink substrate are mounted on the heat sink.

[0009] Preferably, the heat dissipation substrate is provided with a plurality of strip-shaped mounting holes evenly distributed along its length direction.

[0010] Preferably, the heat dissipation substrate is made of silicon carbide aluminum.

[0011] Preferably, a plastic shell covering the DCB substrate is provided on the heat dissipation substrate.

[0012] Preferably, two guide frames are installed on the radiator at intervals, the heat dissipation substrate is slidably installed on the guide frames, the guide frames are threadedly connected with adjustment screws, the adjustment screws are threadedly connected to the heat dissipation substrate, and the lower ends of the adjustment screws are rotatably connected to the radiator.

[0013] Preferably, a nickel-plated layer is provided on the surface of the heat sink.

[0014] Preferably, the DCB substrate is made of insulating material.

[0015] Preferably, the plastic shell is provided with a plurality of inwardly protruding recesses.

[0016] Preferably, the radiator comprises a ceramic body and a circulating water channel arranged in the ceramic body, and the circulating water channel is arranged in an "S" shape.

[0017] (III) Beneficial effects

[0018] The heat block is formed by the heat dissipation substrate and DCB substrate, and the chip resistor replaces the power chip and simulates the actual power module with the heat dissipation substrate and DCB liner. The temperature adjustment range of the chip resistor is -45℃-125℃, which can effectively simulate the temperature changes that may actually occur in the power chip;

[0019] After the chip resistor generates heat, the heat is transferred to the radiator through the heat dissipation substrate for heat dissipation, and the temperature of the radiator and the heat dissipation substrate is detected by the temperature measuring element, so as to test the heat dissipation efficiency of the radiator to the entire heat block under different temperatures generated by the chip resistor, and simulate the heat dissipation effect under actual working conditions in turn;

[0020] At the same time, the heat dissipation performance of the radiator can also be improved based on the test results to enhance the heat dissipation effect in actual working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model;

[0022] Figure 2 It is a three-dimensional structural schematic diagram of an embodiment of the utility model;

[0023] Figure 3 It is a schematic diagram of the top view of the structure of an embodiment of the utility model;

[0024] exist Figures 1 to 3 In the figure, the corresponding relationship between the component names or lines and the figure numbers is as follows:

[0025] Radiator 1 , heat block 2 , heat dissipation substrate 21 , DCB substrate 22 , chip resistor 23 , strip-shaped mounting hole 24 , plastic shell 3 , inner recess 30 , guide frame 4 , and adjustment screw 5 . DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0027] See also Figure 1-Figure 3 As shown, in the embodiment of the utility model, a thermal resistance test fixture for a power module is proposed, which is to simulate the heat dissipation effect of the power chip under the actual working temperature, so as to improve the heat dissipation performance before the subsequent assembly application, and ensure the heat dissipation under the actual application conditions. Specifically, the fixture includes a heat sink 1 and a heat block 2 installed on the heat sink 1, wherein the heat block 2 includes a heat dissipation substrate 21 and a DCB substrate 22 soldered on the heat dissipation substrate 21, and the DCB substrate 22 is provided with a plurality of protrusions, and the protrusions are soldered and fixed with chip resistors 23. The heights of the heat dissipation substrate 21, the DCB substrate 22 and the protrusions are the same as the parameters for installing the power chip in the actual power module. The power chip is replaced by an edge resistor. Since the chip resistor 23 can adjust the temperature within the range of -45°C-125°C, In this way, the operation of the power chip under different temperature conditions can be simulated. After the chip resistor 23 generates heat, the heat is transferred to the heat sink 1 for heat dissipation based on the heat dissipation substrate 21. At the same time, a plurality of temperature measuring elements in contact with the heat dissipation substrate 21 are installed on the heat sink 1. The temperatures of the heat sink 1 and the heat dissipation substrate 21 are detected by the temperature measuring elements, so as to obtain the heat dissipation effect of the heat sink 1 on the chip resistor 23 at the current simulated temperature. By changing the temperature of the chip resistor 23, multiple temperature conditions that may be generated by the power chip are simulated, thereby effectively realizing the simulated heat dissipation effect.

[0028] At the same time, a plurality of strip-shaped mounting holes 24 evenly distributed along the length direction of the heat dissipation substrate 21 are opened, and the position of the heat block 2 relative to the radiator 1 is adjusted through the strip-shaped mounting holes 24 to further study the heat dissipation effect of the relative mounting position.

[0029] At the same time, the heat dissipation substrate 21 is made of silicon carbide aluminum, which has a good heat exchange effect.

[0030] At the same time, a nickel-plated layer with a thickness of 3um is provided on the surface of the radiator 1, which has higher hardness and better shock resistance than copper material. Secondly, its thermal expansion coefficient is higher than that of copper material, that is, it has stronger temperature cycling ability, which is very suitable for occasions with vibration environment and impact load underground.

[0031] The DCB substrate 22 is made of insulating material to prevent the heat sheet resistor from contacting the heat dissipation base plate 21 .

[0032] The radiator 1 includes a ceramic body and a circulating water channel arranged in the ceramic body. The circulating water channel is arranged in an "S" shape. The heat dissipation effect is improved according to the arranged circulating water channels, and the heat dissipation effect is achieved by utilizing the circulating flow speed of the radiator 1.

[0033] Specifically, a plastic shell 3 covering the DCB substrate 22 is provided on the heat dissipation substrate 21 , and the internal components are covered by the plastic shell 3 to simulate the heat generation effect in an actual packaging situation.

[0034] At the same time, a plurality of inwardly protruding recesses 30 are provided on the plastic shell 3. The arrangement of the recesses 30 actually simulates the occupation of the internal space in a packaging situation, so that the simulated structure of the entire heat block 2 is closer to reality.

[0035] In order to further simulate that a certain gap will be generated between the heat dissipation substrate 21 and the radiator 1 under vibration, it is also necessary to conduct a simulation test on the heat dissipation effect under the condition of the gap, so two guide frames 4 are installed on the radiator 1 at intervals, and the heat dissipation substrate 21 is slidably installed on the guide frames 4, and the guide frames 4 are threadedly connected with an adjusting screw 5, and the adjusting screw 5 is threadedly connected to the heat dissipation substrate 21, and the lower end of the adjusting screw 5 is rotatably connected to the radiator 1; the heat dissipation substrate 21 is slidable and stopped relative to the guide frame 4 by rotating the adjusting screw 5, and the distance between the heat dissipation substrate 21 and the radiator 1 is adjusted by a feeler gauge and then stopped by the adjusting screw 5, thereby achieving the simulation of the specific heat dissipation effect when a gap is generated between the heat dissipation substrate 21 and the radiator 1, thereby being able to truly simulate the heat dissipation condition under vibration, and ensuring good heat dissipation after subsequent actual assembly.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "inner", "outer", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0038] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A power module thermal resistance test tool, characterized in that: comprising a heat sink and a heat block mounted on the heat sink; The heat block comprises a heat dissipation substrate and a DCB substrate soldered on the heat dissipation substrate, the DCB substrate is provided with a plurality of protrusions, and chip resistors are soldered and fixed on the protrusions; A plurality of temperature measuring elements in contact with the heat dissipation substrate are mounted on the heat sink.

2. A power module thermal resistance test fixture according to claim 1, characterized in that: The heat dissipation substrate is provided with a plurality of strip-shaped mounting holes evenly distributed along the length direction thereof.

3. A power module thermal resistance test fixture according to claim 2, characterized in that: The heat dissipation substrate is made of silicon carbide aluminum.

4. A power module thermal resistance test tool according to any one of claims 1 to 3, characterized in that: A plastic shell covering the DCB substrate is disposed on the heat dissipation substrate.

5. The power module thermal resistance test fixture according to claim 4, characterized in that: Two guide frames are installed on the radiator at intervals, the heat dissipation substrate is slidably installed on the guide frames, the guide frames are threadedly connected with adjustment screws, the adjustment screws are threadedly connected to the heat dissipation substrate, and the lower end of the adjustment screws is rotatably connected to the radiator.

6. A power module thermal resistance test fixture according to claim 4, characterized in that: The surface of the radiator is provided with a nickel plating layer.

7. A power module thermal resistance test tool according to claim 4, characterized in that: The DCB substrate is made of insulating material.

8. The power module thermal resistance test tool according to claim 4, characterized in that: The plastic shell is provided with a plurality of inwardly protruding concave parts.

9. The power module thermal resistance test tool according to claim 4, characterized in that: The radiator includes a ceramic body and a circulating water channel arranged in the ceramic body, and the circulating water channel is arranged in an "S" shape.

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