The adoption of two paralleled inverters using magnetically coupled inductors is an emerging and effective way to feed the three-phase load, which can be operated with interleaved or zero-common-mode (CM) pulsewidth modulation (PWM). The zero-CM PWM can significantly reduce the CM current and electromagnetic interference (EMI), but worsen the circulating current as compared to the interleaved method. Preventing the coupled inductor saturation is the main rule of coupled inductor design, which is determined by the peak value of the circulating current. This article presents a detailed analysis of the zero-CM PWM effects on the circulating current. A detailed exploration of the pulse position shift technique is presented, and a novel modified modulation strategy referred to as phase-shifted zero-CM PWM is proposed, which can significantly reduce the peak value of circulating current and therefore lower the saturation flux density of coupled inductors. The phase-shifted zero-CM PWM is discussed with respect to the traditional method, and the specific design of phase shift angle leads to the reduced peak value of the circulating current, which can finally reduce the size of coupled inductors. The theoretical and experimental results are presented to evaluate the performance of the proposed method against the traditional zero-CM PWM.

中文翻译：

---

用于降低带耦合电感器的两个并联逆变器中的循环电流的移相零 CM PWM

采用使用磁耦合电感器的两个并联逆变器是一种新兴且有效的方式来为三相负载供电，该三相负载可以在交错或零共模 (CM) 脉宽调制 (PWM) 下运行。零 CM PWM 可以显着降低 CM 电流和电磁干扰 (EMI)，但与交错方法相比，会使循环电流恶化。防止耦合电感饱和是耦合电感设计的主要原则，由环流峰值决定。本文详细分析了零 CM PWM 对循环电流的影响。详细介绍了脉冲位置偏移技术，并提出了一种新的改进调制策略，称为相移零 CM PWM，可显着降低环流峰值，从而降低耦合电感的饱和磁通密度。相移零共模PWM相对于传统方法进行了讨论，相移角的具体设计导致环流峰值减小，最终可以减小耦合电感的尺寸。提出了理论和实验结果来评估所提出的方法对传统零 CM PWM 的性能。最终可以减小耦合电感的尺寸。提出了理论和实验结果来评估所提出的方法对传统零 CM PWM 的性能。最终可以减小耦合电感的尺寸。提出了理论和实验结果来评估所提出的方法对传统零 CM PWM 的性能。