基于映射原理的多电平逆变器SVPWM

SVPWM for Multilevel Inverter Based on Mapping Principle

级联型多电平逆变器空间矢量脉宽调制(SVPWM)具有提高直流电压利用率,可为电机提供跟踪圆形磁链的电压等优点,但随着电平数的升高其调制复杂度也随之升高。提出一种新的SVPWM方法,该方法利用映射原理将参考电压分解为基矢量和2电平矢量,将复杂的多电平SVPWM转化为简单的2电平SVPWM,再利用逆映射决定合成多电平逆变器参考电压的开关矢量及开关状态的作用时间和作用顺序。该方法适用于任意n电平逆变器的调制。最后通过11电平逆变器的仿真和实验验证了该方法的有效性。

The cascaded multilevel inverter has the ability of improveing utilization ration DC voltage ,providing the advantages of track the voltage of circular flux for motor, but as the number of level increases, the complexity of mod- ulation increase, too.A novel simplified space vector pulse width modulation（SVPWM） strategy is proposed ,which de- composes the reference voltage into base vector and two-level vectors based on mapping principle, and the SVPWM of multilevel is transformed into simple SVPWM of two-level.Moreover,the switch vectors which compose the reference voltage of multilevel inverter, the duration and sequence of switch states are determined by reverse mapping.The pro- posed strategy can be extended to any n-level inverter without increasing the complexity.The validity of this method is verified by simulation and experimental results with eleven-level inverter.