级联型多电平变换器单元电路控制策略仿真

Simulation of control strategy of cascade multilevel inverter cell circuit

针对级联型多电平变换器需要四象限运行的工况,提出以双H桥的电压胞拓扑作为多电平变换器单元电路的方案。其前H桥为整流器,采用滞环电流控制策略实现直流电压稳定和近似单位功率因数的双向能量流动;后H桥为逆变器,采用载波相移SPWM技术。通过建立整流器的滞环电流控制模型和三单元级联多电平逆变器相移技术控制模型,对变换器进行双向能量传输运行的过渡过程分析和逆变器输出级联电压波形分析。仿真结果表明该拓扑及控制策略满足四象限运行要求。

In response to the requirement of four quadrant operation conditions by cascade type multilever converter,this paper proposes the double H bridge cell voltage topology used as multilever converter unit circuit.It consists of front H bridge which works as rectifier,capable of realizing dc voltage stability and approximate unit of power factor two-way energy flow using hysteresis current control strategy,and rear H bridge which function as inverter adopting carrier phase shift SPWM technology.The paper introduces an analysis of transition process of two-way energy transmission operation of the converter and analysis of the voltage waveform of inverter output cascade by developing the rectifier hysteresis current control model and three unit cascade multilevel inverter phase shift technology control model.The simulation results show that the topology and the control strategy meet the requirements of the four quadrant operation.