耦合电感三电平双降压式逆变器

双降压式逆变器是一种可靠性和转换效率均较高的新型逆变器,针对其直流电压利用率低、桥臂输出仍为双极性PWM调制波的缺陷,提出了一种新型三电平双降压式逆变器,充分利用双降压式逆变器的半周工作模式,使桥臂输出改进为三电平PWM调制波,并降低了功率器件的电压应力。但在电感电流断续区可能出现高的器件电压尖峰,通过将两电感耦合,可对桥臂电压进行钳位消除电压尖峰,同时也减小了磁件本身的大小。耦合电感三电平双降压式逆变器在减小体积重量的同时保持了高效率、高可靠性。试验结果验证了以上分析的正确性。

Coupled-Inductance Three-Level Dual Buck Inverter

Dual Buck inverter (DBI) is a new topology which has the characteristics of high frequency and high efficiency. But the output voltage of the bridge is a bipolar PWM waveform and component voltage stress is high, just like half bridge inverter. To overcome these problems, a novel three-level dual Buck inverter, which has uni-polarity PWM waveforms output and low voltage stress, is presented in this paper. And the half load-cycle operation mode of DBI is remained in the new inverter. But over-voltage may occur when the inductor current is discontinuous. To overcome this problem, two inductors of the inverter are coupled together, and then the bridge voltage can be clamped, and the volume and weight of magnetic component are reduced at the same time. The filter size of the new inverter is reduced and the merits of high efficiency and high reliability are remained at the same time. Experimental result verifies the above analysis.