多电平逆变器四象限运行控制策略的研究

Research on Control Strategy of Multi-level Inverter Four-quadrant Work

针对当前级联型多电平逆变器的能量变换只能单向传递,无法应用于需四象限运行的变负荷拖动的问题,设计了以双H桥为电压胞的电压胞拓扑,并采用滞环电流控制策略实现整流器近似单位功率因数的双向能量流动。逆变器控制采用载波移相SPWM技术,通过上位机与电压胞控制器的通信,实现启动/停、参数设置、故障诊断处理等任务,且电压胞具有结构简单、易于模块化设计、单元工作对称、开关负荷平衡,输出电压谐波小等优点。实验证明,该拓扑及控制策略满足四象限运行的要求。

This paper designs voltage of cell topology using a dual H-bridge and lag bi-directional energy flow of the hysteresis current control strategy to achieve the rectifier approximate unity power factor.The inverter is controlled by the carrier phase-shifted SPWM technology,it communicates through the host computer and realizes the voltage cell controller, change the start/stop, parameter setting,fault diagnosis processing tasks.Voltage package has advantages of simple structure, easy modular design, symmetry of the unit work, switch load balancing, small output voltage harmonic. The experimental results verify the topology and control strategies meet the requirements of the four-quadrant operation.