Dead time effect compensation method and device

Abstract

The invention discloses a dead time effect compensation method and a dead-time effect compensation device. The method comprises the following steps of: presetting a mapping relation between an integer rotating speed point and a three-phase dead time compensation value to obtain a target three-phase dead time compensation value which corresponds to a current rotating speed point; adding the target three-phase dead time compensation value with a given three-phase duty ratio to obtain a practical three-phase duty ratio needed by compensation; and further obtaining a target three-phase SVPWM (Space Vector Pulse Width Modulation) parameter which corresponds to the practical three-phase duty ratio to generate a target three-phase SVPWM waveform so as to finish compensation for the three-phase SVPWM waveform under the rotating speed point. According to the method and the device, the problem that the current three-phase duty ratio of the three-phase inverter circuit output waveform of a motor controller is lower than the given three-phase duty ratio due to the presence of the dead time is solved, and the control efficiency of the motor controller is further increased.

Description

technical field [0001] The invention belongs to the technical field of motor control, and in particular relates to a dead zone effect compensation method and device suitable for motor controllers and based on space vector pulse width modulation (SVPWM). Background technique [0002] At present, permanent magnet synchronous motor controllers usually use Space Vector Pulse Width Modulation (SVPWM, Space Vector Pulse Width Modulation) to control the motor. Among them, SVPWM is a relatively novel control method that has developed rapidly in recent years. It uses the pulse width modulation wave generated by the specific switching mode composed of six power switching elements of the three-phase power inverter to make the output three-phase waveform as close as possible to an ideal sine wave. [0003] In the existing three-phase inverter circuit of the motor controller, ideally, the upper and lower power switching devices of the same bridge arm of the three-phase inverter circuit ...

AI Technical Summary

Problems solved by technology

However, the existence of the dead time brings a very harmful dead time effect to the three-phase inverter, that is, the existence of the dead time makes the duty cycle of the actually output three-phase SVPWM waveform lower than the given duty cycle, wherein, The duty cycle is the proportion of the high level in one cycle; when the duty cycle is lower than the given duty cycle, the effective value of the output voltage of the motor controller will be reduced, which in turn will cause the Control inefficiencies, ultimately reducing motor system efficiency

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