基于共模电压抑制的六相电机空间矢量调制

为了解决双Y移30°六相电机与逆变器组构成的系统中存在共模电压的问题,提出一种新的六相电机空间矢量脉宽调制方法以有效降低共模电压的幅值和变化频率.利用三相解耦PWM (pulse w idth modulation)算法将六相电压源逆变器的电压矢量分解到两个三相电压源逆变器中,得到和六相矢量空间解耦(vector space decomposition,VSD)方法近似的控制效果,再利用无零矢量PWM调制方法分别进行合成.对仿真结果的分析表明,保证了较好的电流、转矩和转速性能情况下,共模电压峰值为直流母线电压的1/6,共模电压的变化频率也显著降低.

Space vector modulation of six-phase motor based on suppression of common-mode voltage

In order to solve the problem of common-mode voltage in the system composed of dual Y shift 30° six-phase motors and inverters, a novel space vector PWM method for six-phase motors was proposed to effectively reduce the amplitude and frequency of common-mode voltage in this paper. Three-phase decomposition PWM algorithm was used to decompose the voltage vector of six-phase voltage source inverter into two voltage vectors of three-phase voltage source inverters, and the control effect was similar to that by six-phase VSD method. Afterwards, non-zero vector PWM method was used for synthesis, respectively. The analysis of simulation results shows that the common-mode voltage peak is 1/6 of DC bus voltage and the frequency of common-mode voltage reduced significantly, under the prerequisite for good current, torque and rotating speed performance.