Discharging circuit fault detection device and method

Abstract

The invention provides a discharging circuit fault detection device. The discharging circuit fault detection device comprises a diode D1, a power device Q1, a divider resistor R2, a divider resistor R3, a fault judgment device U1 and a control unit M1; R1 is in series connection with the Q1 and then is in parallel connection with a positive bus U+ and a negative bus U-; the D1 is in parallel connection to the two ends of the R1; the R2 is in series connection with the R3 and then is in parallel connection with one end of the R1 and the negative bus U-; an input end of the U1 is connected withan OUT1 output point between the R2 and the R3, and an output end of the U1 is connected with the M1; the M1 sends an on-off command of the Q1, and the U1 judges whether or not the Q1 has a short-circuit or open-circuit fault according to a divider voltage value VOUT1 of the OUT1 and informs the M1. The discharging circuit fault detection device has the advantages that the structure is simple, andthe discharging circuit fault can be detected in time and fed back to the control unit, thereby preventing hardware equipment from being damaged.

Description

technical field [0001] The invention belongs to the technical field of electronic circuits, in particular to a discharge circuit fault detection device and detection method Background technique [0002] If the motor driver needs to perform four-quadrant operation, the bus voltage will increase due to the current being fed back to the capacitor under the brake power generation state. At this time, the discharge circuit is required to release this part of the energy. The commonly used discharge circuit consumes excess energy through the discharge resistor. If discharge is not required, the discharge circuit needs to be disconnected. If the discharge circuit fails, it will cause the discharge circuit to fail to discharge in time when it needs to be discharged, which may damage the drive hardware, or cause the drive bus voltage to be too high and cause an alarm. [0003] However, there is basically no fault judgment device in the conventional discharge circuit. Generally, the d...

AI Technical Summary

Problems solved by technology

Commonly used discharge circuits consume excess energy through discharge resistors. If discharge is not required, the discharge circuit needs to be disconnected

If the discharge circuit fails, it will cause the discharge circuit to fail to discharge in time when it needs to be discharged, which may damage the drive hardware, or cause the drive bus voltage to be too high and cause an alarm

[0003] However, there is basically no fault judgment device in the conventional discharge circuit. Generally, the driver chip of the power device is used to detect whether the power device is faulty. This method requires a dedicated driver chip, which is costly, and there is also a way to detect the current of the discharge circuit. , this method needs to increase the current sampling resistor or current Hall sensor to collect the current signal, and increase the analog amplifier circuit to amplify the collected current signal and the isolation circuit, the circuit is complicated and the hardware cost is high

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