CN217561643U - Motor controller MOSFET testing arrangement based on many pulse tests - Google Patents

Abstract

The utility model discloses a motor controller MOSFET testing device based on multi-pulse testing, which comprises two MOSFETs with half-bridge structures, namely a half-bridge upper tube Q1 and a half-bridge lower tube Q2; the positive electrode of the direct current power supply is connected with the drain electrode of the half-bridge upper tube Q1, and the negative electrode of the direct current power supply is connected with the source electrode of the half-bridge lower tube Q2; one end of the inductor L is connected with the positive electrode of the direct-current power supply, and the other end of the inductor L is connected with a connection point between the half-bridge upper tube Q1 and the half-bridge lower tube Q2; the pulse signal generator is connected with the grid of the half-bridge lower tube Q2, the current probe is used for measuring drain current, the first voltage probe is used for measuring drain voltage, and the second voltage probe is used for measuring grid voltage; the first voltage probe, the second voltage probe and the current probe are connected with an oscilloscope. The utility model can obtain the working electrical parameters of the MOSFET under specific working conditions and judge whether the MOSFET is in a safe working area; and the reasonable protection time required by the motor controller can be determined according to the actual working electrical parameter condition.

Description

Motor controller MOSFET testing arrangement based on many pulse tests

Technical Field

The utility model relates to a power electronics measures technical field, especially relates to a machine controller MOSFET testing arrangement based on many pulse tests.

Background

The motor controller is a key component in an electric system, the MOSFET is used as an important device of the motor controller, the working safety of the MOSFET determines the reliability of the whole electric system, when the motor controller works under specific working conditions such as motor short circuit, overlarge current up to hundreds of amperes can be formed, the transient temperature rise of the MOSFET is very large, protection is carried out in time under the condition, otherwise, the junction temperature of the MOSFET is too high to be damaged, and the use of the motor controller is further influenced.

In practical application, different designs of motor controllers use different MOSFETs and different supply voltages, and loop inductances and resistances of the different MOSFETs often have certain differences, so that electrical parameters of the MOSFETs in the controllers are different from each other, and it is important to test the operational safety of the MOSFETs and determine reasonable protection times for different motor drivers.

Disclosure of Invention

The utility model provides a machine controller MOSFET testing arrangement based on many pulse tests through testing the work electrical parameter of MOSFET under specific operating mode such as motor short circuit, judges whether MOSFET is in safe workspace to confirm the required reasonable guard time of machine controller according to the MOSFET actual work electrical parameter condition.

The technical scheme of the utility model as follows:

a motor controller MOSFET testing device based on multi-pulse testing comprises a MOSFET, a direct-current power supply, an inductor, a capacitor, a resistor, a pulse signal generator, an oscilloscope, a first voltage probe, a second voltage probe and a current probe; the MOSFETs are two MOSFETs of a half-bridge structure respectively, namely a half-bridge upper tube Q1 and a half-bridge lower tube Q2; the positive electrode of the direct current power supply DC is connected with the drain electrode of the half-bridge upper tube Q1, and the negative electrode of the direct current power supply DC is connected with the source electrode of the half-bridge lower tube Q2; one end of the inductor L is connected with the positive electrode of the direct-current power supply, and the other end of the inductor L is connected with a connection point between the half-bridge upper tube Q1 and the half-bridge lower tube Q2; one end of the capacitor is connected with the positive electrode of the direct current power supply, and the other end of the capacitor is connected with the negative electrode of the direct current power supply; the pulse signal generator is connected with a grid electrode of the half-bridge lower tube Q2, the current probe is connected with the half-bridge lower tube Q2 and used for measuring drain current, the first voltage probe is connected with the half-bridge lower tube Q2 and used for measuring drain voltage, and the second voltage probe is connected with the half-bridge lower tube Q2 and used for measuring grid voltage; the first voltage probe, the second voltage probe and the current probe are connected with an oscilloscope.

Grid resistance of tube Q1 on the half-bridge is resistance R1, and one end is connected to tube Q1's on the half-bridge grid, and the other end is connected to tube Q1's on the half-bridge source electrode.

The gate resistor of the half-bridge lower tube Q2 is a resistor R2, one end of which is connected to the gate of the half-bridge lower tube Q2, and the other end of which is connected to the positive terminal of the gate control voltage Vgs of the pulse signal generator.

The first voltage probe is a high voltage isolation probe.

The utility model provides a machine controller MOSFET test platform and method based on many pulse tests through testing the work electrical parameter of MOSFET under specific operating mode such as motor short circuit, can effectively judge whether MOSFET is in safe workspace to confirm the required reasonable guard time of machine controller according to MOSFET actual work electrical parameter condition.

Drawings

Fig. 1 is a schematic diagram of a test platform in an embodiment of the present invention;

fig. 2 is a schematic waveform diagram of the principle in an embodiment of the present invention;

fig. 3 is a waveform diagram of an actual test in an embodiment of the present invention.

Detailed Description

The invention will be further described with reference to the following drawings and examples:

the utility model provides a motor controller MOSFET testing arrangement based on many pulse tests, can evaluate MOSFET work safety effectively, on the one hand, this test can obtain MOSFET under specific operating mode such as motor short circuit work electrical parameter, judges whether MOSFET is in safe workspace; on the other hand, the test can determine the reasonable protection time required by the motor controller according to the actual working electrical parameter condition of the MOSFET.

As shown in fig. 1, the motor controller MOSFET testing apparatus based on multi-pulse testing includes a MOSFET, a dc power supply, an inductor, a capacitor, a resistor, a pulse signal generator, an oscilloscope, a first voltage probe, a second voltage probe, and a current probe. The MOSFETs are two MOSFETs of a half-bridge structure respectively, namely a half-bridge upper tube Q1 and a half-bridge lower tube Q2; the positive electrode of the direct current power supply DC is connected with the drain electrode of the half-bridge upper tube Q1, and the negative electrode of the direct current power supply DC is connected with the source electrode of the half-bridge lower tube Q2; one end of the inductor L is connected with the positive electrode of the direct-current power supply, and the other end of the inductor L is connected with a connection point between the half-bridge upper tube Q1 and the half-bridge lower tube Q2; one end of the capacitor C is connected with the positive electrode of the direct-current power supply, and the other end of the capacitor C is connected with the negative electrode of the direct-current power supply; the resistor R1 is a grid resistor of a half-bridge upper tube Q1, one end of the resistor R1 is connected to the grid of the Q1, and the other end of the resistor R1 is connected to the source electrode of the Q1; the resistor R2 is a gate resistor of the half-bridge lower tube Q2, one end of the resistor R is connected to the gate of the Q2, and the other end of the resistor R is connected to the positive end of a gate control voltage Vgs; the pulse signal generator is connected with a grid electrode of the half-bridge lower tube Q2, the current probe is connected with the half-bridge lower tube Q2 and used for measuring drain current, the first voltage probe is connected with the half-bridge lower tube Q2 and used for measuring drain voltage, and the second voltage probe is connected with the half-bridge lower tube Q2 and used for measuring grid voltage; the first voltage probe, the second voltage probe and the current probe are connected with an oscilloscope.

The utility model discloses specific application method is as follows, including following step:

s1, a current probe is adopted to connect and measure a drain current Id passing through a half-bridge lower tube Q2, a first voltage probe is connected and measures a drain voltage Vds of the half-bridge lower tube Q2, and a second voltage probe is connected and measures a gate voltage Vgs of the half-bridge lower tube Q2; and displaying three signals of drain current Id, drain voltage Vds and gate voltage Vgs of the half-bridge lower tube Q2 by using an oscilloscope.

And S2, electrifying the direct-current power supply and the pulse signal generator, and gradually increasing the pulse number of grid control voltage Vgs signals output by the pulse signal generator to gradually increase the drain current of the half-bridge lower tube Q2 from small to large so as to avoid the sudden increase of the current to burn out the MOS tube.

S3, enabling a grid control voltage Vgs signal to be a square wave pulse signal, enabling t 0-t 2 to be 1 pulse period, and repeating the pulse period for multiple times; in the period, t 0-t 1 is the switching-on process of the half-bridge lower tube Q2, in the period, the DC voltage of the direct-current power supply acts on the inductor L, and the drain current of the half-bridge lower tube Q2 rises linearly; t 1-t 2 are the turn-off process of the half-bridge lower tube Q2, during which the half-bridge lower tube Q2 is turned off, the drain current of the half-bridge lower tube Q2 is reduced to zero, the drain voltage Vds is increased and peak appears, and the body diode of the half-bridge upper tube Q1 continues current; in the next period, the half-bridge lower tube Q2 is saturated and conducted again, and the drain current of the half-bridge lower tube Q2 is superposed and increased; a plurality of pulse cycles are repeated, and the drain current of the half-bridge lower tube Q2 can rise to a larger current, so that working electrical parameters equivalent to specific working conditions such as motor short circuit and the like are achieved.

And S4, recording and analyzing the actual test waveform, judging whether the MOSFET works in the safety area or not according to the definition of the MOSFET working safety area, and determining the time for working and needing protection under the electrical parameters.

As shown in fig. 3, for the practical test waveform diagram in the embodiment of the present invention, it can be seen from the diagram that through multiple pulse tests, the maximum value of the drain current of the half-bridge lower tube Q2 reaches 413A, and this parameter is equal to the actual working electrical parameter under the specific working conditions such as motor short circuit in the motor controller, and the working safety zone definition according to this MOSFET can determine whether it is in the safety working zone, and at the same time, can determine the time that it can work and needs protection under this electrical parameter.

The above embodiments are provided only for illustrating the technical concepts and features of the present invention, and the purpose of the embodiments is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention, and the protection scope of the present invention cannot be limited thereby. All modifications made according to the spirit of the main technical scheme of the present invention shall be covered within the protection scope of the present invention.

Claims (4)

1. Motor controller MOSFET testing arrangement based on many pulse tests, its characterized in that:

the device comprises a MOSFET, a direct current power supply, an inductor, a capacitor, a resistor, a pulse signal generator, an oscilloscope, a first voltage probe, a second voltage probe and a current probe; the MOSFETs are two MOSFETs of a half-bridge structure respectively, namely a half-bridge upper tube Q1 and a half-bridge lower tube Q2; the positive electrode of the direct current power supply DC is connected with the drain electrode of the half-bridge upper tube Q1, and the negative electrode of the direct current power supply DC is connected with the source electrode of the half-bridge lower tube Q2; one end of the inductor is connected with the positive electrode of the direct-current power supply, and the other end of the inductor is connected with a connection point between the half-bridge upper tube Q1 and the half-bridge lower tube Q2; one end of the capacitor is connected with the positive electrode of the direct current power supply, and the other end of the capacitor is connected with the negative electrode of the direct current power supply; the pulse signal generator is connected with a grid electrode of the half-bridge lower tube Q2, the current probe is connected with the half-bridge lower tube Q2 and used for measuring drain current, the first voltage probe is connected with the half-bridge lower tube Q2 and used for measuring drain voltage, and the second voltage probe is connected with the half-bridge lower tube Q2 and used for measuring grid voltage; the first voltage probe, the second voltage probe and the current probe are connected with an oscilloscope.

2. The multi-pulse test based motor controller MOSFET test apparatus of claim 1, wherein:

grid resistance of tube Q1 on the half-bridge is resistance R1, and one end is connected to tube Q1's on the half-bridge grid, and the other end is connected to tube Q1's on the half-bridge source electrode.

3. The multi-pulse test based motor controller MOSFET test apparatus of claim 2, wherein:

the gate resistor of the half-bridge lower tube Q2 is a resistor R2, one end of which is connected to the gate of the half-bridge lower tube Q2, and the other end of which is connected to the positive terminal of the gate control voltage Vgs of the pulse signal generator.

4. The multi-pulse test based motor controller MOSFET testing device of claim 3, wherein:

the first voltage probe is a high voltage isolation probe.

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