永磁同步电机直接转矩控制新型占空比调制策略

针对传统永磁同步电机直接转矩控制系统转矩脉动和磁链脉动较大，现有占空比调制策略计算复杂等问题，提出一种新型占空比调制策略.该调制策略利用定子磁链和扇区电压矢量的作用角区分转矩脉动和磁链脉动在控制系统中的权重系数，并设计新型开关表，保证在任一控制周期中最佳电压矢量的选择.在保证系统计算量较低的前提下，利用权重系数和最佳电压矢量推导最优占空比计算公式.仿真和实验结果证明，所提出的新型占空比调制策略可以大幅度抑制转矩脉动和磁链脉动，获得较好的稳态运行性能，并保持系统快速动态响应性能.

Novel Duty Ratio Modulation Strategy for PMSM DTC System

In order to suppress the significant torque ripple and flux linkage ripple in CDTC(conventional direct torque control)-driven PMSM(permanent magnet synchronous motor)， and to reduce the calculations in conventional duty ratio modulation strategies， a novel duty ratio modulation strategy for PMSM DTC(direct torque control) system was proposed. The impact factors of torque and flux linkage ripples could be distinguished using the proposed strategy through the active angle between stator linkage and sector vector. A new switching table was designed to ensure the optimal choice of voltage vector. The simplified duty ratio calculation equations were obtained with the minimum calculations. Simulation and experimental results show that the novel modulation strategy can maintain the dynamic response in CDTC and suppress torque and flux linkage ripples efficiently.