【摘要】 提出一种基于三相四桥臂逆变器的正弦波脉宽调制(SPWM)状态交换控制策略,用于降低传统的三相三桥臂逆变器因电路不对称而产生的共模电压。该策略是在前3个桥臂进行载波移相控制的基础上,对被控制桥臂进行状态交换,以避免零状态的出现,突破了原来的载波移相策略对调制指数的限制,能在任意调制指数下有效地抑制共模电压。经过优化状态交换策略,在保持良好的共模电压抑制效果基础上,得到了具有最优差模特性的方案。实验验证了SPWM状态交换策略的有效性。更多还原

【Abstract】 This paper proposes a novel sinusoidal pulse width modulation(SPWM) state-exchange control strategy based on three-phase four-leg inverter structure,which can reduce the huge amount of common-mode(CM) voltage of the tradi-tional three-phase three-leg inverters produced by the asymmetry of the circuit.Predicated on the application of the SPWM carrier phase-shifting control in the first three legs,the state-exchange of the controlled leg is adopted to avoid zero-state.This strategy breaks through the limitation of SPWM modulation index of the original carrier phase-shifting control and can be used to reduce the CM voltage efficiently with arbitrary modulation index.To optimize state-exchange strategy,the scheme is found,which has the best difference mode characteristic as well as the best restraint effect of CM voltage.The experiment proves the effectiveness of the SPWM state-exchange strategy.更多还原