一种改进的永磁同步电机直接转矩控制方法

A Modified Direct Torque Control of Permanent Magnet Synchronous Motor

提出了一种改进的基于占空比调制的永磁同步电机直接转矩控制(DTC)方法。分析了在不同电压矢量作用下传统DTC的转矩波动和磁链波动的规律。为减小转矩波动和磁链波动,提出一种改进的占空比调制方法。该方法可使每个控制周期初始的转矩误差和磁链误差同时参与占空比计算,既减小了转矩波动也抑制了磁链波动,同时还充分利用了零电压矢量使转矩减小的特性。推导了占空比的计算公式,经过Simulink仿真和基于d SPACE平台的试验,证明了该方法能有效减小转矩波动和磁链波动。

A modified direct torque control （DTC） method based on duty ratio modulated for permanent magnet synchronous motor was proposed. The rule of torque ripple and stator flux ripple under different voltage vectors of conventional DTC was analyzed. In order to decrease the ripple of torque and stator flux, a modified duty ratio modulated was proposed. In this method, both torque error and flux error were used to calculate the duty ratio in each control period. Moreover, it made full use of the characteristic of the zero voltage vector to reduce the torque. The calculation formula of duty cycle was deduced, simulation and experimental results showed that this method could effectively reduce the torque ripple and the flux ripple.