A pulsewidth modulation (PWM) scheme is presented for three-phase high-speed electric drives using coupled inductors with a very low series output inductance that generate multilevel output voltages with an elevated PWM frequency. Two inverter legs are used in each phase, connected in parallel using coupled inductors with magnetic cross-coupling. The PWM switching of the inverter legs is controlled using carrier signals 180° apart. Rather than changing these carrier signals on the zero crossovers of the three-phase reference signals to improve the PWM line voltage, the reference signals are modified instead: enhanced PWM control. This approach allows the use of compensation signals to eliminate flux jumps in the magnetic cores commonly associated with carrier switching. Hence, the flux in the magnetic cores follows predictable patterns, with the peak flux reduced considerably. This, in turn, allows the inductor design to be reduced in size and weight. The enhanced PWM control described is also shown to reduce the load current THDf and the load voltage harmonic volt-seconds. The feasibility of the enhanced PWM control is verified using both simulations and experimental results of a 10-kW (208 V/28 A, 300 Vdc) laboratory prototype.

中文翻译：

---

适用于高速电力驱动器的高质量 PWM 方案


提出了一种用于三相高速电力驱动器的脉宽调制 (PWM) 方案，该方案使用具有极低串联输出电感的耦合电感器，可生成具有升高的 PWM 频率的多级输出电压。每相使用两个逆变器支路，使用具有磁性交叉耦合的耦合电感器并联连接。逆变器支路的 PWM 开关是使用相隔 180° 的载波信号控制的。不是通过改变三相参考信号过零处的这些载波信号来改善 PWM 线电压，而是修改参考信号：增强 PWM 控制。这种方法允许使用补偿信号来消除通常与载波切换相关的磁芯中的磁通跳跃。因此，磁芯中的通量遵循可预测的模式，峰值通量显着降低。这反过来又允许减小电感器设计的尺寸和重量。所描述的增强型 PWM 控制还可以降低负载电流 THDf 和负载电压谐波伏秒。使用 10 kW（208 V/28 A，300 Vdc）实验室原型的仿真和实验结果验证了增强型 PWM 控制的可行性。