A detection method and system for a PWM module in a motor drive device

Abstract

The invention belongs to the field of motor control, and especially relates to a PWM module detection method and system in a motor driver. According to the detection method and the system provided by the invention, first of all, the digital output signals of a PWM module at a normal state is calculated according to motor parameters so that the conduction and closure time of a switch tube in a driving circuit can be controlled, the purpose of obtaining a motor input current is realized, and the input current is stored. When the PWM module is broken, the output of a driving unit is abnormal, and as a result, the actual input current of a motor is also abnormal. However, the motor employs a current closed loop control scheme, the current detection unit feeds a detected real-time current back to a comparison unit for comparing the real-time current with a preset input current, and if a comparison result is abnormal, it is determined that the PWM module is broken, PWM output is stopped, and motor shutdown protection is realized.

Description

technical field [0001] The invention belongs to the field of motor control, in particular to a detection method and system for a PWM module in a motor drive device. Background technique [0002] At present, the driving device of the brushless DC motor is mostly controlled by pulse width modulation (PWM), and the digital output signal is generally sent by the microprocessor to control the analog driving circuit and then control the motor. Therefore, the correctness and stability of the PWM module itself has a decisive impact on the drive control of the motor. When a microelectronic fault occurs in the PWM module, such as a timer fault, which causes an abnormal change in the adjustment of the duty cycle, the output of the PWM will inevitably be abnormal, causing the switch tube to be turned on or off abnormally, and the motor cannot run normally, or even cause The motor is short-circuited, and the motor is burned due to excessive current and excessive heat generation of the m...

AI Technical Summary

Problems solved by technology

When a microelectronic fault occurs in the PWM module, such as a timer fault, which causes an abnormal change in the adjustment of the duty cycle, the output of the PWM will inevitably be abnormal, causing the switch tube to be turned on or off abnormally, and the motor cannot run normally, or even cause The motor is short-circuited, and the motor is burned due to excessive current and excessive heat generation of the motor

However, there is currently no simple and efficient system or method to detect the working status of the PWM module in the motor drive device

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