Real-time detection method for phase potential of motor under control of PWM

Abstract

The invention discloses a real-time detection method for a phase potential of a motor under control of PWM. According to the invention, after two kinds of interphase wire potentials of a motor are detected by utilizing a voltage sensor, filtering is carried out on a high-frequency PWM waveform by a second-order low pass filter of a single operational amplifier so as to remove high-frequency components and burrs in the wire potentials by filtration, thereby obtaining singles of the two interphase wire potentials of the motor; and then the singles of the two interphase wires are sent to an AD port of a microcontroller and are converted into digital quantities; after that, a real-time operation is carried out according to an internal relation between the wire potentials and phase potentials of the motor so as to calculate phase potential values of three phases of the motor. According to the above-mentioned real-time detection method for the phase potential of the motor, a technological base is provided for realization of a high performance torque control ring and a potential control ring in a weak-magnetic speed regulation operation.

Description

technical field [0001] The invention relates to a motor phase potential real-time detection method under PWM control, in particular to a motor phase potential real-time detection method suitable for sine wave motors and non-sinusoidal wave motors, which belongs to the digital detection technology of motors. Background technique [0002] Sinusoidal motors such as permanent magnet brushless DC motors, asynchronous induction motors, and permanent magnet synchronous motors, as well as non-sinusoidal motors such as switched reluctance and double salient poles, usually require the installation of a power converter to drive and control the speed and torque. Most power converters use PWM control methods such as SPWM control and space voltage vector control. These control methods control the voltage applied to the motor windings by turning on and off the power switch tube, so as to control the motor current and output power. the goal of. However, these control methods make the poten...

AI Technical Summary

Problems solved by technology

However, these control methods make the potential waveform of the motor divided into many small pulse waveforms, accompanied by a large number of glitches, which cannot realize real-time online detection and calculation of the motor potential and torque

For some motor control systems that require special requirements of torque loop or potential loop, it will bring a series of problems, which will affect the accuracy and real-time performance of the control.

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