关于逆变器对电网供电质量优化控制

Optimal Control of Inverter Power Supply Quality

并网逆变器需要具有较高的稳定控制精度、快速的动态响应性能以及较强的抗干扰能力。而传统单环重复控制方法动态特性较差,基于逆变测电流反馈的重复双环控制方法和网测电流反馈但环控制方法纹波较大、稳定精度不高。针对难点提出了基于网测电流反馈的双闭环控制方法。利用基于极点配置的控制方法改善逆变器瞬时电压PID控制器,运用MATLAB仿真验证,结果表明基于极点配置的PID控制方法使逆变器动态响应速度快速,输出电压THD低,稳态精度高。将基于极点配置大设计方法用于逆变器电压电流双环控制系统,仿真结果表明这种逆变器电压电流双环控制系统与传统PID双环控制系统响应更快,具有良好的输出电压总谐波畸变率低;同时,指出电感电流内环电压外环双环系统具有自动限流功能,提高了系统的可靠性,从而验证了理论分析的正确性。

The grid connected inverter needs high stability control precision,fast dynamic response performance and strong anti-interference ability.But the traditional single loop repetitive control method has poor dynamic characteristics.Based on the double loop control method of inverter current feedback and the network measurement current feedback,the ring control method has large ripple and low stability accuracy.A double closed loop control method based on net measurement current feedback is proposed.The PID controller based on pole placement is used to improve the instantaneous voltage of inverter.The MATLAB simulation results show that the PID control method based on pole placement makes the inverter dynamic response fast,the output voltage THD is low,and the steady-state accuracy is high.The design method is based on pole assignment control system for the voltage and current double inverter.The simulation results show that the inverter voltage and current dual loop control system has faster response than the traditional PID loop control system,total harmonic distortion of output voltage and good rate is low;at the same time,the inductance current loop and outer voltage loop system has automatic current limiting function,which can improve the reliability of the system,so as to verify the correctness of the theoretical analysis.