单相电力电子变压器整流级复合无源控制

Composite Passivity Control of Rectifier Stage for Single-Phase Power Electronic Transformer

针对单相级联H桥型电力电子变压器整流级易受输入电压、负载电阻等参数影响,及传统PI双闭环控制性能较差的问题,提出一种电流内环的复合控制策略。在无源控制(PBC)的基础上加入扩张状态观测器(ESO)作为扰动观测,并进行补偿。通过MATLAB/Simulink软件搭建三级型电力电子变压器整流级模型,将结合扩张状态观测器的无源控制与传统PI控制、无源控制进行对比。结果表明:提出的控制策略能有效降低交流侧电流谐波量,且系统动态响应速度快、鲁棒性更好。

Aiming at the problem that the rectifier stage of single-phase cascaded H-bridge power electronic transformer is easily affected by input voltage,load resistance and other parameters,as well as the poor performance of traditional PI double closed loop control,a composite control strategy with current inner loop is proposed.Extended state observer(ESO)was added to the passivity based control(PBC)as a disturbance observation and compensated.The rectifier stage model of a three-stage power electronic transformer was built-in MATLAB/Simulink software,and the passivity based control combined with the extended state observer was compared with the traditional PI control and passivity based control.Results show that the control strategy proposed in this paper can effectively reduce the amount of AC current harmonics,and the system dynamic response is fast and has better robustness.