Power module VBS working current test circuit and test method

Abstract

The invention provides a power module VBS working current test circuit and test method. The power module VBS working current test circuit comprises a power supply, a control chip, a first upper bridge arm, a second upper bridge arm, a third upper bridge arm, a first lower bridge arm, a second lower bridge arm, a third lower bridge arm, a signal generator, a first relay, a second relay, a third relay and a plurality of control power supplies. The input end of the first relay is used for inputting U-phase working current, and the output end of the first relay is connected with the source electrode of the first upper bridge arm; the input end of the second relay is used for inputting V-phase working current, and the output end of the second relay is connected with the source electrode of the second upper bridge arm; the input end of the third relay is used for inputting W-phase working current, and the output end of the third relay is connected with the source electrode of the third upper bridge arm; the testing function of the working current is realized by controlling the first relay, the second relay and the third relay. The method is high in test accuracy and good in test reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of power modules, and in particular to a power module VBS operating current test circuit and a test method. Background Art

[0002] Intelligent Power Module (IPM) is a power drive product that combines power electronics and integrated circuit technology. It has the advantages of high current, low saturation voltage and high withstand voltage of GTR (high power transistor), and the advantages of high input impedance, high switching frequency and low driving power of MOSFET (field effect transistor). In the production process of power modules, some defective products will inevitably appear. Parameter testing can effectively screen out defective products that do not meet the specifications and prevent them from entering the market, thereby improving the overall quality level of the product. By performing regular parameter testing on high-voltage integrated circuits, quality changes in the production process can be monitored, problems can be discovered in time, and measures can be taken to correct them. This helps to ensure the stability and consistency of product quality. Parameter testing is an indispensable link in the research and development of high-voltage integrated circuits.

[0003] With the rapid development of power electronics, the intelligentization and integration of power devices are its development trend. Power modules integrate high-voltage ICs, power chips and other devices. We have many parameters to test products. For example, there are more than 500 parameters of the module, 70% of which are IC parameters, and the remaining 30% are also related to IC. VBS is the core parameter of IC in the module. It is a necessary test item in the product development stage and factory production process.

[0004] However, the current VBS high-side working current test may have the following problems: insufficient detection accuracy may cause a large deviation between the current measurement value and the actual value, and factors such as surrounding electromagnetic interference and temperature changes may affect the accuracy of the measurement results. For example, a strong electromagnetic field may cause errors in the measuring instrument. Difficulty in dynamic current measurement: In actual work, the VBS high-side current may change dynamically, and traditional measurement methods may have difficulty accurately capturing the changes in dynamic current, resulting in low test accuracy and poor reliability. Summary of the invention

[0005] The invention provides a power module VBS working current test circuit, aiming to solve the problems of low current test accuracy and poor test reliability of existing intelligent power modules.

[0006] In a first aspect, an embodiment of the present invention provides a power module VBS working current test circuit, including: a power supply, a control chip, a first upper bridge arm, a second upper bridge arm, a third upper bridge arm, a first lower bridge arm, a second lower bridge arm, a third lower bridge arm, a signal generator, a first relay, a second relay, a third relay and a plurality of control power supplies;

[0007] The power supply is used to power the control chip; the input end INUH of the first upper bridge arm, the input end INVH of the second upper bridge arm and the input end INWH of the third upper bridge arm are respectively connected to the signal generator and used as control ends of high and low level PWM pulses;

[0008] The source of the first upper bridge arm is connected to the drain of the first lower bridge arm, the source of the second upper bridge arm is connected to the drain of the second lower bridge arm, and the source of the third upper bridge arm is connected to the drain of the third lower bridge arm; the gate of the first upper bridge arm, the gate of the second upper bridge arm, the gate of the third upper bridge arm, the gate of the first lower bridge arm, the gate of the second lower bridge arm, and the gate of the third lower bridge arm are respectively connected to the control chip; the drain of the first upper bridge arm is respectively connected to the drain of the second upper bridge arm and the drain of the third upper bridge arm and are commonly connected to the bus voltage input terminal P; the source of the first lower bridge arm is used to connect to the module external pin NU terminal, the source of the second lower bridge arm is used to connect to the module external pin NV terminal, and the source of the third lower bridge arm is used to connect to the module external pin NW terminal;

[0009] The U-phase bootstrap terminal VB1 of the control chip is connected to the positive electrode of the control power supply, the V-phase bootstrap terminal VB2 of the control chip is connected to the positive electrode of the control power supply, the W-phase bootstrap terminal VB3 of the control chip is connected to the positive electrode of the control power supply, and the negative electrode of the control power supply is grounded;

[0010] The input end of the first relay is used to input the U-phase working current, and the output end of the first relay is connected to the source of the first upper bridge arm; the input end of the second relay is used to input the V-phase working current, and the output end of the second relay is connected to the source of the second upper bridge arm; the input end of the third relay is used to input the W-phase working current, and the output end of the third relay is connected to the source of the third upper bridge arm; the working current test function is realized by controlling the first relay, the second relay and the third relay.

[0011] Preferably, the power module VBS working current test circuit also includes a first capacitor, the two ends of which are respectively connected to the power supply and the COM port of the control chip for filtering out high-frequency signals; the COM port of the control chip is also grounded.

[0012] Preferably, the power module VBS operating current test circuit further includes a second capacitor, and two ends of the second capacitor are respectively connected to the COM port of the control chip and the RS port of the control chip.

[0013] Preferably, the power module VBS operating current test circuit further includes a first resistor, one end of the first resistor is connected to the EN port of the control chip, and the other end of the first resistor is used to connect to a fixed power supply.

[0014] In a second aspect, an embodiment of the present invention provides a power module VBS operating current test method, the test method is implemented based on the power module VBS operating current test circuit as described above, and the test method includes the following steps:

[0015] S1. Place the sample to be tested on the test fixture and fix the sample to be tested;

[0016] S2. Connect the first relay, the second relay and the third relay to the test sample without power supply, so that the circuit remains in the on state;

[0017] S3, applying necessary fixed power supply conditions to the functional pins of the power module, wherein the fixed power supply conditions are VCC = 15V, EN = 5V, VFAULT = 5V, INVL, INUL and INWL = 0V;

[0018] S4. Test the static working current of VB: Use the signal generator to control the high and low levels of INUH, INVH and INWH to 0-5V, and measure the static working current of VBS when the phase is at a high or low level;

[0019] S5. Test the dynamic working current of VB: input a square wave of 20K or more to INUH, INVH and INWH through the signal generator, and measure the dynamic working current of VBS when the phase is turned on or off;

[0020] S6: After the test is completed, the first relay, the second relay and the third relay are disconnected;

[0021] S7. Finally, disconnect all power supplies.

[0022] Preferably, the S4 specifically comprises the following steps:

[0023] The signal generator is used to control the high and low levels of INUH, INVH, and INWH to 0 to 5V, the working current of the VBU phase is tested, the power supply of VBU is turned on, and then the second relay and the third relay are disconnected. At this time, the value measured by the current detector is the VBS working static current.

[0024] Preferably, the S5 specifically includes the following steps:

[0025] Input square waves of 20K or more to INUH, INVH and INWH through a signal generator to test the working current of the VBU phase, turn on the power supply to VBU, and then disconnect the second relay and the third relay. At this time, the value measured by the current detector is the VBS working dynamic current.

[0026] Compared with the prior art, the beneficial effect of the present invention lies in that the power supply is used to power the control chip; the input terminal INUH of the first upper bridge arm, the input terminal INVH of the second upper bridge arm and the input terminal INWH of the third upper bridge arm are respectively connected to the signal generator, which are used as the control terminals of the high and low level PWM pulses; the source of the first upper bridge arm is connected to the drain of the first lower bridge arm, the source of the second upper bridge arm is connected to the drain of the second lower bridge arm, and the source of the third upper bridge arm is connected to the drain of the third lower bridge arm; the gate of the first upper bridge arm, the gate of the second upper bridge arm, the gate of the third upper bridge arm, the gate of the first lower bridge arm, the gate of the second lower bridge arm and the gate of the third lower bridge arm are respectively connected to the control chip; the drain of the first upper bridge arm is respectively connected to the drain of the second upper bridge arm and the drain of the third upper bridge arm and are commonly connected to the bus voltage input terminal P; the source of the first lower bridge arm is used to connect the module The source of the second lower bridge arm is used to connect the external pin NU end of the module, and the source of the third lower bridge arm is used to connect the external pin NW end of the module; the U-phase bootstrap end VB1 of the control chip is connected to the positive pole of the control power supply alone, the V-phase bootstrap end VB2 of the control chip is connected to the positive pole of the control power supply alone, and the W-phase bootstrap end VB3 of the control chip is connected to the positive pole of the control power supply alone, and the negative pole of the control power supply is grounded; the input end of the first relay is used to input the U-phase working current, and the output end of the first relay is connected to the source of the first upper bridge arm; the input end of the second relay is used to input the V-phase working current, and the output end of the second relay is connected to the source of the second upper bridge arm; the input end of the third relay is used to input the W-phase working current, and the output end of the third relay is connected to the source of the third upper bridge arm; the working current test function is realized by controlling the first relay, the second relay and the third relay. In this way, the working current of the power module can be optimized and tested well, the test accuracy can be improved, and the product test reliability can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be described in detail below in conjunction with the accompanying drawings. The above and other aspects of the present invention will become clearer and easier to understand through the detailed description made in conjunction with the following drawings. In the accompanying drawings:

[0028] Figure 1 is a circuit diagram of a power module VBS operating current test circuit provided by an embodiment of the present invention;

[0029] Figure 24 is a circuit diagram of an anti-backfeed protection circuit provided by an embodiment of the present invention.

[0030] In the figure, 1. control chip, 2. first upper bridge arm, 3. second upper bridge arm, 4. third upper bridge arm, 5. first lower bridge arm, 6. second lower bridge arm, 7. third lower bridge arm, 8. control power supply, 9. signal generator. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] Embodiment 1

[0033] Combined with Figure 1 As shown, an embodiment of the present invention provides a power module VBS working current test circuit, including: a power supply VCC, a control chip 1, a first upper bridge arm 2, a second upper bridge arm 3, a third upper bridge arm 4, a first lower bridge arm 5, a second lower bridge arm 6, a third lower bridge arm 7, a signal generator 9, a first relay K1, a second relay K2, a third relay K3 and multiple control power supplies 8.

[0034] Among them, the first upper bridge arm 2, the second upper bridge arm 3, the third upper bridge arm 4, the first lower bridge arm 5, the second lower bridge arm 6, and the third lower bridge arm 7 are all triode transistors.

[0035] The power supply VCC is used to power the control chip 1; the input end INUH of the first upper bridge arm 2, the input end INVH of the second upper bridge arm 3 and the input end INWH of the third upper bridge arm 4 are respectively connected to the signal generator 9, which are used as control ends of high and low level PWM pulses.

[0036] The source of the first upper bridge arm 2 is connected to the drain of the first lower bridge arm 5, the source of the second upper bridge arm 3 is connected to the drain of the second lower bridge arm 6, and the source of the third upper bridge arm 4 is connected to the drain of the third lower bridge arm 7; the gate of the first upper bridge arm 2, the gate of the second upper bridge arm 3, the gate of the third upper bridge arm 4, the gate of the first lower bridge arm 5, the gate of the second lower bridge arm 6 and the gate of the third lower bridge arm 7 are respectively connected to the control chip 1; the drain of the first upper bridge arm 2 is respectively connected to the drain of the second upper bridge arm 3 and the drain of the third upper bridge arm 4 and is commonly connected to the bus voltage input terminal P; the source of the first lower bridge arm 5 is used to connect to the module external pin NU end, the source of the second lower bridge arm 6 is used to connect to the module external pin NV end, and the source of the third lower bridge arm 7 is used to connect to the module external pin NW end.

[0037] Specifically, the control power supply 8 includes three bootstrap terminals VB (1 / 2 / 3) respectively connected to the U-phase / V-phase / W-phase of the control chip 1. The U-phase bootstrap terminal VB1 of the control chip 1 is connected to the positive electrode of the corresponding control power supply 8, the V-phase bootstrap terminal VB2 of the control chip 1 is connected to the positive electrode of the corresponding control power supply 8, the W-phase bootstrap terminal VB3 of the control chip 1 is connected to the positive electrode of the corresponding control power supply 8, and the negative electrodes of the three control power supplies 8 are grounded.

[0038] The input end of the first relay K1 is used to input the U-phase working current, and the output end of the first relay K1 is connected to the source of the first upper bridge arm 2; the input end of the second relay K2 is used to input the V-phase working current, and the output end of the second relay K2 is connected to the source of the second upper bridge arm 3; the input end of the third relay K3 is used to input the W-phase working current, and the output end of the third relay K3 is connected to the source of the third upper bridge arm 4; the working current test function is realized by controlling the first relay K1, the second relay K2 and the third relay K3.

[0039] Among them, the module bus voltage input terminal P is suspended; the upper bridge arm signal input terminals INUH, INVH, and INWH of the power module are connected to the signal generator 9 as high and low level PWM pulse control terminals; the temperature simulation signal output terminal RTH is suspended; the IC power supply VCC output terminal VCC is connected to 15V; the lower bridge arm signal input terminals INVL, INUL, and INWL of the power module are suspended; the power module enable input / output terminals EN and VFAULT are connected to 5V; the U phase output terminal of the power module is grounded; the V The W-phase output terminal of the power module is grounded; the U-phase bootstrap terminal VBU of the power module is connected to the first control power supply 8 separately, and is connected to the positive electrode of the control power supply 8, and the negative electrode of the control power supply 8 is connected to the common ground; the V-phase bootstrap terminal VBV of the power module is connected to the second control power supply 8 separately, and is connected to the positive electrode of the control power supply 8, and the negative electrode of the control power supply 8 is connected to the common ground; the W-phase bootstrap terminal VBW of the power module is connected to the third control power supply 8 separately, and is connected to the positive electrode of the control power supply 8, and the negative electrode of the control power supply 8 is connected to the common ground;

[0040] Specifically, the power supply VCC is used to power the control chip 1; the input terminal INUH of the first upper bridge arm 2, the input terminal INVH of the second upper bridge arm 3 and the input terminal INWH of the third upper bridge arm 4 are respectively connected to the signal generator 9, which are used as the control terminals of the high and low level PWM pulses; the source of the first upper bridge arm 2 is connected to the drain of the first lower bridge arm 5, the source of the second upper bridge arm 3 is connected to the drain of the second lower bridge arm 6, and the source of the third upper bridge arm 4 is connected to the drain of the third lower bridge arm 7; the gate of the first upper bridge arm 2, the gate of the second upper bridge arm 3, the gate of the third upper bridge arm 4, the gate of the first lower bridge arm 5, the gate of the second lower bridge arm 6 and the gate of the third lower bridge arm 7 are respectively connected to the control chip 1; the drain of the first upper bridge arm 2 is respectively connected to the drain of the second upper bridge arm 3 and the drain of the third upper bridge arm 4 and are jointly connected to the bus voltage input terminal P; the source of the first lower bridge arm 5 is used to connect to the module external pin NU terminal, the second lower bridge arm 3 is connected to the drain of the third upper bridge arm 4, and the drain of the third upper bridge arm 7 is ... The source of arm 6 is used to connect the NV end of the module external pin, and the source of the third lower bridge arm 7 is used to connect the NW end of the module external pin; the U-phase bootstrap end VB1 of the control chip 1 is connected to the positive pole of the control power supply 8 alone, the V-phase bootstrap end VB2 of the control chip 1 is connected to the positive pole of the control power supply 8 alone, the W-phase bootstrap end VB3 of the control chip 1 is connected to the positive pole of the control power supply 8 alone, and the negative pole of the control power supply 8 is grounded; the input end of the first relay K1 is used to input the U-phase working current, and the output end of the first relay K1 is connected to the source of the first upper bridge arm 2; the input end of the second relay K2 is used to input the V-phase working current, and the output end of the second relay K2 is connected to the source of the second upper bridge arm 3; the input end of the third relay K3 is used to input the W-phase working current, and the output end of the third relay K3 is connected to the source of the third upper bridge arm 4; the working current test function is realized by controlling the first relay K1, the second relay K2 and the third relay K3. In this way, the working current of the power module can be optimized and tested well, the test accuracy can be improved, and the product test reliability can be ensured.

[0041] In this embodiment, the power module VBS working current test circuit also includes a first capacitor C1, the two ends of the first capacitor C1 are respectively connected to the power supply VCC and the COM port of the control chip 1, and are used to filter out high-frequency signals; the COM port of the control chip 1 is also grounded. The first capacitor C1 is a high-frequency filter capacitor of the control chip 1, connected to VCC and COM, and as close as possible to the output end of the control chip 1, and its function is to filter out high-frequency signals.

[0042] In this embodiment, the power module VBS working current test circuit further includes a second capacitor C2, and two ends of the second capacitor C2 are respectively connected to the COM port of the control chip 1 and the RS port of the control chip 1.

[0043] In this embodiment, the power module VBS working current test circuit also includes a first resistor R1, one end of the first resistor R1 is connected to the EN port of the control chip 1, and the other end of the first resistor R1 is used to connect to a fixed power supply to facilitate circuit protection.

[0044] Embodiment 2

[0045] like Figure 2 As shown, an embodiment of the present invention provides a power module VBS operating current test method, the test method is implemented based on the power module VBS operating current test circuit as in the above embodiment 1, and the test method includes the following steps:

[0046] S1. Place the sample to be tested on the test fixture and fix the sample to be tested;

[0047] S2. When the test sample is without power supply, first connect the first relay K1, the second relay K2 and the third relay K3 to keep the circuit open;

[0048] S3, applying necessary fixed power supply conditions to the functional pins of the power module, wherein the fixed power supply conditions are VCC = 15V, EN = 5V, VFAULT = 5V, INVL, INUL and INWL = 0V;

[0049] S4. Test the static working current of VB: control the high and low levels of INUH, INVH and INWH by 0-5V through the signal generator 9, and measure the static working current of VBS when the phase is at a high level or a low level;

[0050] S5. Test the dynamic working current of VB: input square waves of 20K or more to INUH, INVH and INWH through the signal generator 9, and measure the dynamic working current of VBS when the phase is turned on or off;

[0051] S6, the test is completed, disconnecting the first relay K1, the second relay K2 and the third relay K3;

[0052] S7. Finally, disconnect all power supplies.

[0053] In this embodiment, step S4 specifically includes the following steps:

[0054] The signal generator 9 is used to control the high and low levels of INUH, INVH and INWH to 0-5V, and the working current of the VBU phase is tested. The power supply of VBU is turned on, and then the second relay K2 and the third relay K3 are disconnected. At this time, the value measured by the current detector is the VBS working static current.

[0055] In this embodiment, step S5 specifically includes the following steps:

[0056] The signal generator 9 inputs square waves of 20K or more to INUH, INVH and INWH to test the working current of the VBU phase, turns on the power supply to the VBU, and then disconnects the second relay K2 and the third relay K3. At this time, the value measured by the current detector is the VBS working dynamic current.

[0057] In the specific implementation, the sample to be tested is placed on the test fixture and fixed; the test sample is first connected to the first relay K1, the second relay K2 and the third relay K3 without power supply; the necessary fixed power supply conditions VCC = 15V, EN = 5V, VFAULT = 5V, INVL, INUL, INWL = 0V are applied. The high and low levels of INUH, INVH and INWH are controlled by the signal generator to 0&5V. For example, to test the working current of the VBU phase, turn on the power supply to VBU, and then disconnect the second relay K2 and the third relay K3. At this time, the value measured by the current detector is the VBS working static current. A square wave of more than 20K is input to INUH, INVH and INWH through the signal generator 9. For example, to test the working current of the VBU phase, turn on the power supply to VBU, and then disconnect the second relay K2 and the third relay K3. At this time, the value measured by the current detector is the VBS working dynamic current; after the test is completed, the first relay K1, the second relay K2 and the third relay K3 are disconnected; finally, all power supplies are disconnected. The working current test function is realized by controlling the first relay K1, the second relay K2 and the third relay K3, so that the working current of the power module can be well optimized and tested, the test accuracy can be improved, and the product test reliability can be ensured.

[0058] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, article or device. In the absence of more restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, article or device including the element.

[0059] The embodiments of the present invention are described above in conjunction with the accompanying drawings. What is disclosed is only the preferred embodiment of the present invention. However, the present invention is not limited to the above-mentioned specific implementation manner. The above-mentioned specific implementation manner is only illustrative rather than restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms and equivalent changes without departing from the scope of protection of the purpose of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A power module VBS working current test circuit, characterized in that: include: A power supply, a control chip, a first upper bridge arm, a second upper bridge arm, a third upper bridge arm, a first lower bridge arm, a second lower bridge arm, a third lower bridge arm, a signal generator, a first relay, a second relay, a third relay and multiple control power supplies; The power supply is used to power the control chip; the input end INUH of the first upper bridge arm, the input end INVH of the second upper bridge arm and the input end INWH of the third upper bridge arm are respectively connected to the signal generator and used as control ends of high and low level PWM pulses; The source of the first upper bridge arm is connected to the drain of the first lower bridge arm, the source of the second upper bridge arm is connected to the drain of the second lower bridge arm, and the source of the third upper bridge arm is connected to the drain of the third lower bridge arm; The gate of the first upper bridge arm, the gate of the second upper bridge arm, the gate of the third upper bridge arm, the gate of the first lower bridge arm, the gate of the second lower bridge arm and the gate of the third lower bridge arm are respectively connected to the control chip; the drain of the first upper bridge arm is respectively connected to the drain of the second upper bridge arm and the drain of the third upper bridge arm and are commonly connected to the bus voltage input terminal P; the source of the first lower bridge arm is used to connect to the module external pin NU terminal, the source of the second lower bridge arm is used to connect to the module external pin NV terminal, and the source of the third lower bridge arm is used to connect to the module external pin NW terminal; The U-phase bootstrap terminal VB1 of the control chip is connected to the positive electrode of the control power supply, the V-phase bootstrap terminal VB2 of the control chip is connected to the positive electrode of the control power supply, the W-phase bootstrap terminal VB3 of the control chip is connected to the positive electrode of the control power supply, and the negative electrode of the control power supply is grounded; The input end of the first relay is used to input the U-phase working current, and the output end of the first relay is connected to the source of the first upper bridge arm; The input end of the second relay is used to input the V-phase working current, and the output end of the second relay is connected to the source of the second upper bridge arm; The input end of the third relay is used to input the W-phase working current, and the output end of the third relay is connected to the source of the third upper bridge arm; The working current test function is realized by controlling the first relay, the second relay and the third relay.

2. The power module VBS operating current test circuit according to claim 1, characterized in that: The power module VBS working current test circuit also includes a first capacitor, the two ends of which are respectively connected to the power supply and the COM port of the control chip for filtering out high-frequency signals; the COM port of the control chip is also grounded.

3. The power module VBS operating current test circuit according to claim 1, characterized in that: The power module VBS operating current test circuit further includes a second capacitor, and two ends of the second capacitor are respectively connected to the COM port of the control chip and the RS port of the control chip.

4. The power module VBS operating current test circuit according to claim 1, characterized in that: The power module VBS operating current test circuit also includes a first resistor, one end of the first resistor is connected to the EN port of the control chip, and the other end of the first resistor is used to connect to a fixed power supply.

5. A method for testing VBS operating current of a power module, characterized in that: The test method is implemented based on the power module VBS working current test circuit according to any one of claims 1 to 4, and the test method comprises the following steps: S1. Place the sample to be tested on the test fixture and fix the sample to be tested; S2. Connect the first relay, the second relay and the third relay to the test sample without power supply, so that the circuit remains in the on state; S3, applying necessary fixed power supply conditions to the functional pins of the power module, wherein the fixed power supply conditions are VCC = 15V, EN = 5V, VFAULT = 5V, INVL, INUL and INWL = 0V; S4. Test the static working current of VB: Use the signal generator to control the high and low levels of INUH, INVH and INWH to 0-5V, and measure the static working current of VBS when the phase is at a high or low level; S5. Test the dynamic working current of VB: input a square wave of 20K or more to INUH, INVH and INWH through the signal generator, and measure the dynamic working current of VBS when the phase is turned on or off; S6: After the test is completed, the first relay, the second relay and the third relay are disconnected; S7. Finally, disconnect all power supplies.

6. The power module VBS operating current testing method according to claim 5, characterized in that: The S4 specifically comprises the following steps: The signal generator is used to control the high and low levels of INUH, INVH, and INWH to 0 to 5V, the working current of the VBU phase is tested, the power supply of VBU is turned on, and then the second relay and the third relay are disconnected. At this time, the value measured by the current detector is the VBS working static current.

7. The power module VBS operating current testing method according to claim 5, characterized in that: The S5 specifically includes the following steps: Input square waves of 20K or more to INUH, INVH and INWH through a signal generator to test the working current of the VBU phase, turn on the power supply to VBU, and then disconnect the second relay and the third relay. At this time, the value measured by the current detector is the VBS working dynamic current.

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