基于VGLESO和滑模理论的直流配电网母线电压控制策略

Bus Voltage Control Strategy of DC Distribution Network Based on VGLESO and Sliding Mode Theory

针对直流配电网母线电压稳定性问题,设计了一种变增益线性扩张状态观测器(variable gain linear extended state observer,VGLESO),有效地解决了传统高增益线性扩张状态观测器(linear extended state observer extended state observer,LESO)在运行初始阶段输出存在峰值的问题。在此基础上进一步提出了一种变增益滑模自抗扰控制策略,将其应用到直流配电网AC-DC双向变流器控制系统中的电压外环。变增益滑模自抗扰控制策略在不需要增加额外电流传感器的情况下,就能够实现对系统总扰动的快速跟踪和补偿,有效地抑制了母线电压波动,提高了系统的动态响应。从理论上证明了VGLESO和变增益滑模自抗扰控制策略的稳定性。最后通过MATLAB/Simulink验证了该控制策略的可行性与正确性。

In order to solve the problem of voltage stability of DC distribution network bus,a variable gain linear extended state observer(VGLESO)is designed,which effectively solves the problem of peak output of the traditional high gain linear extended state observer(LESO)in the initial stage of operation.Based on this,a variable gain sliding mode active disturbance rejection control(ADRC)strategy is proposed,which is applied to the voltage outer loop of AC-DC bidirectional converter control system in DC distribution network.The variable gain sliding mode active disturbance rejection control strategy can track and compensate the total disturbance of the system without adding additional current transformer,effectively restrain the voltage fluctuation of the bus and improve the dynamic response of the system.The stability of VGLESO and variable gain sliding mode ADRC is proved theoretically.Finally,the feasibility and correctness of the control strategy are verified by MATLAB/Simulink.