CN115047332A - Silicon carbide switch device testing arrangement - Google Patents

Abstract

The application relates to a silicon carbide switching device testing device, which includes a connecting copper bar and a pressure rod; one end of the connecting copper bar is electrically connected to a terminal of a testing capacitor, and the other end of the connecting copper bar is fixedly connected to the middle part of the pressing rod, and is connected to One end of the copper bar is a crimping end to crimp and electrically connect the terminal of the silicon carbide switch device; the angle between the plane where the copper bar is connected and the straight line where the pressing rod is located is within the set angle range, and the distance between the connecting copper bar and the silicon carbide switch is The distance value of the terminal of the device is within the preset distance range, and the present application has the effect of minimizing the stray inductance in the test loop and meeting the test requirements of the silicon carbide switching device.

Description

A silicon carbide switching device testing device

technical field

The present application relates to the field of silicon carbide switching device testing, and in particular, to a silicon carbide switching device testing device.

Background technique

Silicon carbide switching devices are wide bandgap technology. Compared with classic silicon switching devices, silicon carbide switching devices have the characteristics of low on-state resistance and high thermal conductivity, which help to improve the energy efficiency and operating temperature of the final application circuit. Therefore, the development technology of silicon carbide switching devices has gradually been developed. In the process of designing silicon carbide switching devices, it is necessary to test the designed products, so a test platform specially designed for silicon carbide switching devices will be used.

For the silicon carbide switching device test platform, the main circuit stray inductance of the test platform is an important indicator to measure the performance of the test platform. In the switching characteristics of silicon carbide switching devices, the current rises and falls quickly, which requires that the main loop of the test platform has a small enough stray inductance to ensure that the silicon carbide switching device can be accurately tested in the full range during testing. With the increasing requirements for test efficiency, test manufacturers need a more automated test platform. Therefore, an automated mechanical structure for placing silicon carbide switching devices is added on the basis of the original manually operated test platform. An additional automated mechanical structure is connected in series in the main circuit, which increases the miscellaneous inductance of the main circuit and makes the test performance of the automated test platform plummet.

At present, the main circuit stray inductance of the test platform with an automated structure is generally 40nH, which is far lower than the requirements for the test conditions of silicon carbide switching devices.

SUMMARY OF THE INVENTION

In order to automatically test the silicon carbide switching device under the condition of meeting the testing requirements of the silicon carbide switching device, the present application provides a testing device for the silicon carbide switching device.

A silicon carbide switching device testing device provided by the application adopts the following technical solutions:

A silicon carbide switching device testing device, comprising a connecting copper bar and a pressure rod;

One end of the connecting copper bar is electrically connected to the terminal of the test capacitor, the other end of the connecting copper bar is fixedly connected to the middle part of the pressing rod, and one end of the connecting copper bar is a crimping end to be crimped and electrically connected. connecting the terminals of the silicon carbide switching device;

The included angle between the plane where the connecting copper bar is located and the straight line where the pressing rod is located is within a set angle range, and the distance value between the connecting copper bar and the terminal of the silicon carbide switch device is within a preset distance range.

By adopting the above technical solution, the connecting copper bar is connected to the middle part of the pressure bar. On this basis, the posture and position between the connecting copper bar and the pressure bar will affect the miscellaneous inductance in the test loop. By adjusting the connecting copper bar and the pressure bar The attitude relationship between them is to the set angle range and the positional relationship between the connecting copper bar and the pressure rod is adjusted to the preset distance range, so that the stray inductance in the test loop is minimized, thereby meeting the test requirements of silicon carbide switching devices.

Preferably, the portion where the connecting copper bar is fixedly connected with the pressing rod surrounds the pressing rod.

By adopting the above technical solution, the connecting copper bar surrounds the pressing rod, so that the electric charges accumulated in the connecting part between the connecting copper bar and the pressing rod can be dispersed, which is beneficial to reduce the miscellaneous feeling.

Preferably, the crimping end is provided with a pressing tip for pressing the terminal of the silicon carbide switching device.

By adopting the above technical solution, the pressing tip can exert higher pressure on the terminal of the silicon carbide switch device, and the pressing effect is better.

Preferably, there are a plurality of the pressing rods, which are connected to the same connecting copper bar, and are electrically connected in parallel with each other.

By adopting the above technical solution, the terminals of the silicon carbide switch device can be crimped more tightly after a plurality of pressing rods are connected in parallel, and the additional miscellaneous feeling caused by the pressing rods in the device can be reduced.

Preferably, a plurality of the pressing rods are arranged in parallel with each other.

By adopting the above technical solution, the parallel arrangement of the pressure rods can apply a uniform pressure to the terminals of the silicon carbide switch device under the condition of the same length of the pressure rods, and at the same time, the contact structure between the pressure rod ends and the terminals of the silicon carbide switch device can be kept consistent, Therefore, the distribution of the clutter on the plurality of pressure rods is more uniform, which is beneficial to improve the effect of reducing the clutter in the parallel connection of the pressure rods.

Preferably, a first insulating pressure plate is inserted and fitted on the pressure rod, a first through hole is formed on the first insulating pressure plate, the pressure rod is connected in the first through hole by interference, and the first through hole is formed on the first insulating pressure plate. An insulating pressing plate is located on the pressing rod at a position between the connecting copper bar and the crimping end, and the connecting copper bar is crimped on the first insulating pressing plate.

By adopting the above technical solution, the first insulating pressure plate can be fixed at the relative position between the pressure rod and the connecting copper bar, and the use of a metal plate for the first insulating pressure plate can also alleviate the accumulation of tip charges on the pressure rod and the connecting copper bar, which is conducive to reducing the mixed feelings.

Preferably, the first insulating pressure plate is provided with a first accommodating groove for accommodating the connecting copper bar.

By adopting the above technical solution, after accommodating the connecting copper bar, the first accommodating groove can surround at least two sides of the connecting copper bar, and can fix the relative posture between the connecting copper bar and the pressing rod, which is beneficial to the connection between the connecting copper bar and the pressing rod. Fixed connection.

Preferably, the first insulating pressure plate is matched with a second insulating pressure plate, a second through hole is formed on the second insulating pressure plate, and an end of the pressure rod away from the crimping end is inserted into the second through hole Inside, the second insulating pressure plate and the first insulating pressure plate sandwich or clamp the connecting copper bar.

By adopting the above technical solution, the first insulating pressing plate and the second insulating pressing plate can clamp the connecting copper bar on the pressing rod, and can also surround the connecting copper bar, which is beneficial to fix the position of the connecting copper bar on the pressing rod.

Preferably, the second insulating pressure plate is provided with a second accommodating groove for accommodating the connecting copper bar.

By adopting the above technical solution, after accommodating the connecting copper bar, the second accommodating groove can surround at least two side surfaces of the connecting copper bar, which is beneficial to fix the relative posture between the connecting copper bar and the pressing rod.

Preferably, there are a plurality of the connecting copper bars, and the first accommodating groove and the second accommodating groove are arranged in a staggered position.

By adopting the above technical solution, a plurality of connecting copper bars can be connected to terminals with different test capacitances, and a set of devices can also be used to test a plurality of silicon carbide switching devices.

To sum up, the present application at least includes the following beneficial technical effects: the use of connecting copper bars and pressure rods that conform to the set attitude relationship and the preset position relationship reduces the clutter of the test loop to meet the test requirements of silicon carbide switching devices. The use of the first insulating pressure plate with the first accommodating groove and the second insulating pressure plate with the second accommodating groove facilitates the formation of the posture and position between the copper bar and the pressure rod, and at the same time helps to reduce the noise in the test circuit , so that the test results of silicon carbide switching devices are more accurate.

Description of drawings

1 is a schematic diagram of the overall structure of a silicon carbide switching device testing device;

FIG. 2 is an enlarged schematic view showing the connecting copper bar, the pressing rod and the first insulating pressing plate;

FIG. 3 is an enlarged structural schematic diagram of part A in FIG. 1 .

Reference numerals: 10, test capacitance; 11, first electrode; 12, second electrode; 20, automated fixture; 30, connecting copper bar; 40, pressing rod; 41, crimping end; 50, first insulating pressing plate; 51, the first via hole; 52, the first accommodating slot; 60, the second insulating pressure plate; 61, the second via hole; 62, the second accommodating slot.

Detailed ways

The present application will be further described in detail below in conjunction with accompanying drawings 1-3.

In the prior art, a test loop of a silicon carbide switching device includes a test capacitor 10, an automated fixture 20 and a silicon carbide switching device to be tested. The automated fixture 20 includes a first part and a second part, the test capacitor 10, the automated fixture 20 and the to-be-tested. silicon carbide switching devices. The traditional manual test loop is composed of the test capacitor 10 and the silicon carbide switching device to be tested. The existing automatic test loop is composed of the test capacitor 10, the first part, the silicon carbide switching device to be tested and the second part. Compared with the transmission Manual test loops, part 1 and part 2 bring more clutter to the test loop.

The embodiment of the present application discloses a silicon carbide switching device testing device, which can reduce more miscellaneous inductances brought by the automated fixture 20 to the test loop. Referring to FIGS. 1 and 2 , a silicon carbide switching device testing device includes a connecting copper bar 30 , a plurality of pressure bars 40 , a first insulating pressure plate 50 and a second insulating pressure plate 60 . The test capacitor 10 has two flaky and staggered electrodes, a first electrode 11 and a second electrode 12, the two electrodes are arranged in parallel with each other, and the connecting copper bars 30 are pressed against the electrodes by bolts. The connecting copper bar 30 and the electrode are provided with a through hole, and the bolt passes through the hole to fix the connecting copper bar 30 and the electrode, and realize the electrical connection between the connecting copper bar 30 and the electrode. In other embodiments, the connecting copper bars 30 can be welded on the electrodes to achieve fixed and electrical connection.

The pressure bar 40 is welded on the end of the connecting copper bar 30 away from the electrode, and the connecting copper bar 30 is located in the middle of the pressing bar 40 . One end of the connecting copper bar 30 for pressing the terminals of the silicon carbide switch device is the crimping end 41, and the crimping end 41 is provided with a crimping tip, which can be directly formed on the crimping end 41 or can be detachably connected or The assembly is fixedly connected to the crimp end 41 . The crimping tip is used to compress the terminals of silicon carbide switching devices. The switch device has a higher pressure behind the terminals and is crimped more tightly.

After simulation and actual measurement, a plurality of pressure rods 40 are arranged in parallel and electrically connected to the same connection copper bar 30 in parallel, which can improve the pressing effect of the pressure rods 40 on the terminals of the silicon carbide switch device, and can also reduce the miscellaneous inductance. Among them, the test circuit with multiple pressure rods 40 in parallel is 2nH lower than the test circuit with a single pressure rod 40 . The distance between the connecting copper bar 30 and the crimping terminal 41 is different, and the clutter in the test loop is different. The farther the connecting copper bar 30 is from the crimping end 41, the greater the clutter in the test loop where it is located. In the actual measured case, if the distance between the connecting copper bar 30 and the crimping terminal 41 is increased by 14mm, the clutter in the test loop is increased by 8nH. The distance between the connecting copper bar 30 and the crimping end 41 may be 0-14 mm, or may be larger. After simulation and actual measurement, the postures between the connecting copper bar 30 and the crimping terminal 41 are different, and the clutter in the test loop is also different. The closer the posture between the connecting copper bar 30 and the crimping terminal 41 is to be vertical, the less the clutter in the test loop where it is located. The closer the two connecting copper bars 30 or the two electrodes of the test capacitor are, the smaller the stray inductance in the test loop.

As shown in FIG. 2 and FIG. 3 , the first insulating pressure plate 50 and the second insulating pressure plate 60 are arranged in cooperation with each other. The first insulating pressure plate 50 is provided with a plurality of first through holes 51 for the pressure rods 40 to pass through. The interference connection is in the first via hole 51. The second insulating pressure plate 60 is provided with a second via hole 61 for the pressure rod 40 to pass through. The positions of the first via hole 51 and the second via hole 61 correspond to the same pressure The rod 40 passes through the first via hole 51 and the second via hole 61 corresponding to the position. The second insulating pressing plate 60 is fixedly connected to the automated fixture 20 by gluing, heat welding or bolting, and the first insulating pressing plate 50 can also be fixedly connecting to the second insulating pressing plate 60 by gluing, heat welding or bolting.

The process of assembling the first insulating pressing plate 50 and the second insulating pressing plate 60 is as follows: the end of the pressing rod 40 away from the crimping end 41 passes through the first through hole 51, so that the pressing rod 40 is connected to the first insulating pressing plate 50 by interference, The connecting copper bar 30 is provided with a hole for the pressure rod 40 to pass through. The first insulating pressing plate 50 is provided with a first accommodating groove 52 for accommodating the connecting copper bar 30. The opening of the first accommodating groove 52 faces away from the crimping end 41, and the connecting copper bar 30 is pressed into the first accommodating groove 52. The side of 30 away from the first insulating pressing plate 50 is connected to the copper bar 30 and the pressing rod 40 by soldering. The pressing rod 40 connected to the first electrode 11 passes through the first accommodating groove 52 , while the pressing rod 40 connected to the second electrode 12 does not pass through the first accommodating groove 52 and does not pass through the pressing rod 40 of the first accommodating groove 52 The connected connecting copper bars 30 are attached to the surface of the first insulating pressure plate 50 . Insert the second insulating pressing plate 60 from the end of the pressing rod 40 away from the crimping end 41 on the pressing rod 40 and press the connecting copper bar 30. The second insulating pressing plate 60 is provided with a second accommodating groove 62. The second accommodating groove The position of 62 corresponds to the connection copper bar 30 to which the second electrode 12 is connected and accommodates the connection copper bar 30 . There are multiple connecting copper bars 30 on the automated fixture 20 , and at the same time, the positions between the first accommodating groove 52 and the second accommodating groove 62 can be corresponding or dislocated, and the second accommodating groove 62 can also be located in the first accommodating groove 52 The connecting copper bar 30 is surrounded inside, or the first accommodating groove 52 can also be located in the second accommodating groove 62 to surround the connecting copper bar 30 . Finally, the relative positions between the first insulating pressure plate 50 and the second insulating pressure plate 60 are fixed.

The implementation principle of a silicon carbide switching device testing device according to an embodiment of the present application is as follows: the pressure rods 40 are arranged in parallel and parallel to each other, so that the distribution of the clutter on the plurality of pressure rods 40 is more uniform, which is beneficial to reduce the total clutter of the test loop. The connecting copper bar 30 surrounds the pressing rod 40 and the welding path also surrounds the pressing rod 40 , which can disperse the electric charge accumulated at the connection part between the connecting copper bar 30 and the pressing rod 40 and relieve the connection between the pressing rod 40 and the connecting copper bar 30 The degree of charge accumulation at the tip of the point is beneficial to reduce the overall clutter of the test loop. Using the connecting copper bar 30 and the pressing rod 40 that conform to the set attitude relationship and the preset position relationship can reduce the clutter of the test loop and meet the test requirements of silicon carbide switching devices. After the first insulating pressing plate 50 and the second insulating pressing plate 60 press the connecting copper bar 30, it is not only conducive to maintaining the attitude and positional relationship between the connecting copper bar 30 and the pressing rod 40, but also improving the relief of the pressing rod 40 and the connecting copper bar. The effect of the degree of charge accumulation on the tip of the row 30, so that the test results of the silicon carbide switching device are more accurate.

The above are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore: all equivalent changes made according to the structure, shape and principle of the present application should be covered within the scope of the present application. Inside.

Claims (10)

1. A silicon carbide switching device testing device, characterized in that it comprises a connecting copper bar (30) and a pressure rod (40); One end of the connecting copper bar (30) is electrically connected to the terminal of the test capacitor (10), and the other end of the connecting copper bar (30) is fixedly connected to the middle part of the pressing rod (40). One end of the row (30) is a crimping end (41) for crimping and electrically connecting the terminals of the silicon carbide switching device; The included angle between the plane where the connecting copper bar (30) is located and the straight line where the pressing rod (40) is located is within a set angle range, and the connecting copper bar (30) is a distance from the terminal of the silicon carbide switch device. The distance value is within the preset distance range. 2. A silicon carbide switching device testing device according to claim 1, characterized in that: the part where the connecting copper bar (30) is fixedly connected with the pressing rod (40) surrounds the pressing rod (40) . 3 . The silicon carbide switching device testing device according to claim 1 , wherein the crimping end ( 41 ) is provided with a pressing tip for pressing the terminals of the silicon carbide switching device. 4 . 4 . The silicon carbide switching device testing device according to claim 1 , wherein a plurality of said pressure bars ( 40 ) are provided, and are connected to the same connection copper bar ( 30 ), and are mutually connected to each other. 5 . Electrically connected in parallel. 5. A silicon carbide switching device testing device according to claim 4, characterized in that: a plurality of the pressing rods (40) are arranged in parallel with each other. 6. A silicon carbide switching device testing device according to claim 1, characterized in that: a first insulating pressure plate (50) is inserted and fitted on the pressure rod (40), and the first insulating pressure plate (50) ) is provided with a first via hole (51), the pressing rod (40) is connected in the first via hole (51) by interference, and the first insulating pressing plate (50) is in the pressing rod (40). ) located between the connecting copper bar (30) and the crimping end (41), and the connecting copper bar (30) is crimped on the first insulating pressing plate (50). 7 . The silicon carbide switching device testing device according to claim 6 , wherein the first insulating pressure plate ( 50 ) is provided with a first accommodating groove ( 52 ) for accommodating the connecting copper bars ( 30 ). 8 . ). 8. A silicon carbide switching device testing device according to claim 7, characterized in that: the first insulating pressure plate (50) is matched with a second insulating pressure plate (60), and the second insulating pressure plate (60) A second via hole (61) is opened on the top, and the end of the pressing rod (40) away from the crimping end (41) is inserted into the second via hole (61), and the second insulating pressing plate ( 60) The connecting copper bar (30) is sandwiched or clamped with the first insulating pressing plate (50). 9 . The silicon carbide switching device testing device according to claim 8 , wherein: the second insulating pressure plate ( 60 ) is provided with a second accommodating groove ( 62 ) for accommodating the connecting copper bar ( 30 ). 10 . ). 10. A silicon carbide switching device testing device according to claim 9, characterized in that: the connecting copper bars (30) are provided with a plurality of, the first accommodating groove (52) and the second accommodating Slots (62) are misaligned.

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