基于终端积分滑模的三相逆变器自适应下垂控制方法

Adaptive droop control method for three-phase inverters based on terminal integral sliding mode

针对并联逆变器传统下垂控制中电压电流双闭环方法的鲁棒性较差问题,提出了基于自适应鲁棒的终端积分滑模控制律的下垂控制策略。分析滑模控制的收敛速度、响应时间和抖振幅度三个指标,在终端滑模控制律中增加积分环节建立一类扩展滑模控制律。其次,针对系统参数扰动及直流源侧电压的不确定性,利用自适应鲁棒控制实现抑制扰动,将输出电压控制在参考电压的合适范围内,提高了系统的鲁棒性。最后,综合终端积分滑模控制律,根据LC型并联三相逆变器的下垂控制模型,实现逆变器输出电压的自适应鲁棒跟踪控制,有效实现孤岛模式下逆变电源并联干扰抑制。通过MATLAB/Simulink建立并联逆变器的仿真控制模型并进行电路实验,验证了本文控制器的可行性和有效性。

This paper proposes a droop control strategy based on adaptive robust terminal integral sliding mode control law for the poor robustness of the traditional voltage and current double closed-loop method in parallel inverter droop control.Firstly,the convergence speed,response time,and vibration amplitude of sliding mode control are analyzed,and an extended sliding mode control law is established by adding an integral link to the terminal sliding mode control law.Secondly,in response to system parameter disturbance and uncertainty of DC source side voltage,adaptive robust control is used to suppress the disturbance,and the output voltage is controlled within the appropriate range of the reference voltage,which improves the robustness of the system.Finally,based on the terminal integral sliding mode control law,adaptive robust tracking control of the inverter's output voltage has been achieved by using the droop control model of the LC-type parallel three-phase inverter,which efficiently mitigates the disturbance from the inverter power supply's parallel control in island mode.A simulation control model of the parallel inverter has been established by using MATLAB/Simulink and circuit experiments have been carried out to verify the feasibility and effectiveness of the proposed controller.