一种新颖两相调制SVPWM控制策略研究

Research on a Novel Two-phase Modulation SVPWM Control Strategy

针对传统空间电压矢量脉宽调制存在的问题,提出一种新颖空间电压矢量脉宽调制方案。在对传统SVPWM方案进行分析的基础上,采用两相调制方法,根据负载功率因数角选取各扇区内的零电压矢量。该策略使电流在过零时及电流最大时桥臂不换流,使得器件开关频率降低了1/3,且在电流过零时,避免了对该相的死区补偿。仿真及实验结果表明该优化SVPWM控制策略能有效改善电流波形,降低开关损耗,消除了传统方案需要检测电流方向的弊端,且算法简单,易于实现。

A space vector pulse-width modulation（SVPWM） strategy was developed to solve the failure of traditional SVPWM.A two-phase modulation method is adopted based on the analyses of traditional SVPWM,to select the null switching state in each sector according to the power factor angle.As a result,when the current is crossing zero,the corresponding phase does not commute and dead-time compensation is avoided;and when the current is nearing the peak,the corresponding phase also don’t commute,which leads to lower switching losses.The simulation and experimental results validate that the proposed strategy can effectively improve the current wave,minimize the current distortion and reduce the switching losses.Furthermore,the algorithm is easy to implement.