基于LQR的静止同步补偿器滑模控制研究

摘要

在低压配电网中,通常使用静止同步补偿器(STATCOM)补偿无功功率,提出一种综合滑模控制、线性二次型调节器(LQR)方法和空间矢量脉宽调制(SVPWM)的配电网STATCOM (DSTATCOM)新型控制策略,电压外环采用滑模控制来调节和稳定直流电压,同时改变系统动态性能,电流内环采用LQR方法进行设计.搭建了低压DSTATCOM实验平台,实验结果表明采用新型控制策略的DSTATCOM直流电压动态响应快,稳态误差小,系统鲁棒性好,能有效补偿电网无功功率,实现了单位功率因数,电网电流的总谐波畸变率(THD)低于5％.%The static synchronous compensator(STATCOM) is usually used to compensate reactive power in low voltage distribution network.A control design for distributed STATCOM (DSTATCOM) is discussed using sliding mode conrol,linear quadratic regulator(LQR) and space vector pulse width modulatior(SVPWM).The sliding mode control is used to regulate and stablize the direct current voltage in voltage outter loop,the current inner loop is designed using LQR.The low voltage DSTATCOM experimental platform is built.The experimental results show that the proposed DSTATCOM DC voltage has fast dynamic response,the steady-state error is small,the system robustness is good,the reactive power of the grid can be effectively compensated,the unit power factor is achieved,and the total harmonic distortion(THD) of the grid current is less than 5％.