Abstract: The present application relates to a method, circuit, and motor driving system for adaptively adjusting a PWM duty cycle, comprising: sampling a direct current bus voltage and performing a low-pass filtering; determining whether the direct current bus voltage is under-voltage; if yes, entering an under-voltage protection state; and if not, executing the next step; calculating a new duty cycle and a new amplitude; determining whether the new duty cycle is greater than 100%; if yes, applying a weak magnetic control; and if not, adjusting a duty cycle of PWM signals through the new amplitude. Without altering the core current loop, torque loop, or speed loop of the motor driving system, this application adaptively adjusts the PWM duty cycle based on existing sine wave generators and PWM generators, effectively mitigating the impact of direct current bus voltage fluctuations on motor performance, ensuring straightforward operation, and significantly reducing costs.

Abstract: The present application relates to a method, circuit, and motor driving system for adaptively adjusting a PWM duty cycle, comprising: sampling a direct current bus voltage and performing a low-pass filtering; determining whether the direct current bus voltage is under-voltage; if yes, entering an under-voltage protection state; and if not, executing the next step; calculating a new duty cycle and a new amplitude; determining whether the new duty cycle is greater than 100%; if yes, applying a weak magnetic control; and if not, adjusting a duty cycle of PWM signals through the new amplitude. Without altering the core current loop, torque loop, or speed loop of the motor driving system, this application adaptively adjusts the PWM duty cycle based on existing sine wave generators and PWM generators, effectively mitigating the impact of direct current bus voltage fluctuations on motor performance, ensuring straightforward operation, and significantly reducing costs.

Abstract: A method for fault processing of HALL position sensor in brushless direct current motor, comprising: step (1) detecting HALL signals by an edge detection, and recording the times of edge hopping; step (2) determining whether the absolute value of a difference between the rotor position change represented by HALL and an angle value calculated internally by MCU is within the preset error range; if so, updating the angle value to the angle representing the rotor position that is detected by HALL, otherwise, increasing the MCU internal angle value according to an angle increment previously calculated through a motor rotation speed; step (3) obtaining an acceptable range based on an original value of the previous angle increment. The present invention provides an internal degree to record angle, and the motor commutation is accomplished according to the degree angle value recorded by the internal degree.