基于NLESO的交直流微电网双向AC/DC换流器改进滑模稳压控制  

Improved Sliding Mode Voltage Stability Control of Bidirectional AC/DC Converter in AC/DCMicrogrid Based on NLESO

作　　者：周蔚 粟时平[1] 苏杰 欧阳振宇 ZHOU Wei;SU Shiping;SU Jie;OUYANG Zhenyu(Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学,长沙410114

出　　处：《电力电容器与无功补偿》2023年第3期150-157,共8页Power Capacitor & Reactive Power Compensation

摘　　要：针对交直流混合微电网中双向AC/DC换流器在外界扰动下出现的直流母线电压波动问题,设计了一种应用于双向AC/DC换流器的非线性扩张状态观测器(nonlinear extended state observer,NLESO),以实现对分布式电源功率波动和负荷投切变化等不确定因素的快速追踪与补偿,保证了在不同扰动下交直流混合微电网的稳定性。进一步提出了基于NLESO的改进积分滑模控制方法,提高了直流母线电压的控制精度。结合非线性光滑函数设计了滑模趋近律,消除了传统滑模控制中的高频抖振现象。通过Lyapunov理论对系统的稳定性进行分析验证,仿真结果表明该控制方法响应速度快、控制精度高、抗扰动能力强并且无抖振现象。In view of fluctuation of DC bus voltage bidiretional AC/DC converter in AC-DC hybrid microgrid due to external interference,a kind of nonlinear extended state observer(NLESO)for the bidirectional AC/DC converter is designed so to achieve the rapid tracking and compensation of such uncertain factors as the power fluctuation and load switching change of the distibuted power generation,and the stability of the AC-DC hybrid microgrid under different disturbances has also been assured.F urthermore,an improved integrated sliding mode control method based on NLESO is proposed to improve the control accuracy of DC bus voltage.The high frequency chattering phenomenon in traditional sliding mode control is eliminated by the sliding mode approaching law combined with the nonlinear smooth function.The stability of the system is verified by Lyapunov theory.The simulation results show that the control method has the advantages of fast response,high control precision,strong anti-disturbance ability and no chattering phenomenon.

关 键 词：交直流混合微电网 双向AC/DC换流器 滑模控制 非线性扩张状态观测器 非线性光滑函数 

分 类 号：TM721.3[电气工程—电力系统及自动化] TM46