一种新型四象限级联型多电平逆变器拓扑

传统级联型多电平逆变器无法实现能量双向流动.提出一种可四象限运行的新型级联型多电平逆变器拓扑.将PWM整流器与传统H桥逆变器相结合,进而实现了级联型逆变器的四象限运行.提出一种限频式电流滞环控制方法,以获得优良的输入电流控制特性;将载波移相SPWM技术引入到级联型逆变器,有效减小了输出电压电流谐波.对单相三单元逆变器拓扑进行了实验验证.所提出的逆变器拓扑具有输入电流波形近似正弦,无需移相变压器,自动实现能量的双向流动等优点.仿真和实验结果证明了该拓扑的正确性和可行性.

A Novel Four-Quadrant Cascade Multi-Level Inverter

Traditional cascade multi-level inverter could not realize the bi-directional flow of the power. A novel four-quadrant cascade multi-level inverter topology is proposed. Through integrating PWM rectifier into traditional H-bridge inverter, the four-quadrant running of the cascade inverter is realized. A frequency-limited hysteretic current control strategy is proposed to obtain fine control characteristic of input current. The phase-shifted SPWM technology is used in the cascade inverter to reduce harmonious of output voltage and current. And it was verified in a single phase three cell cascaded inverter. The proposed inverter topology has the merits that the input current is near sinusoidal, the phase-shifted transformer is not needed and the bi-directional flow of the power is realized automatically. The simulation and experimental results indicate its validity and feasibility.