基于线性自抗扰技术的SMES储能变流器控制策略

储能系统作为微电网中不可或缺的重要组成部分,对保证微电网的稳定运行和提高微电网电能质量具有重要作用。提出一种基于线性自抗扰控制(linear active disturbance rejection control,LADRC)的超导磁储能系统(superconducting magnetic storage system,SMES)储能变流器控制策略,利用LADRC能够估计并补偿系统扰动,可有效改善储能系统输出电能质量和提高系统鲁棒性。通过对LADRC和比例积分(proportional integral,PI)控制系统进行频率响应特性分析可知,一阶LADRC的反馈补偿器可以等效为一个PI控制器串联一个一阶低通滤波器,能有效抑制系统高频噪声;同时使用根轨迹法分析了LADRC控制系统的稳定性和鲁棒性。MATLAB仿真结果表明,基于LADRC的SMES储能变流器控制策略具有响应速度快、控制精度高、抗扰能力强等优点,其控制效果和鲁棒性均优于传统PI控制器。

Control Strategy for SMES Energy Storage ConverterBased on Linear Active Disturbance Rejection Control

As an indispensable and significant part of the microgrid, the energy storage system plays an important role in the stable operation of the microgrid and ensuring power quality of the microgrid. This paper proposes a control strategy for SMES energy storage converter based on linear active disturbance control (LADRC) , which can estimate and compensate the system disturbance, so that it could effectively improve the power quality and robustness of the energy storage system. Analysis of the frequency response characteristics of the LADRC and PI control systems shows that the feedback compensator of first-order LADRC composed of a PI controller and a first-order low-pass filter in series can effectively suppress the high-frequency noise of the system; And the stability and robustness of the control system of LADRC are analyzed by root locus method. The MATLAB simulation results show that the control strategy for the SMES energy storage converter based on LADRC has the advantages of fast response, high control accuracy and strong anti-disturbance ability, and its control effect and robustness are both better than traditional PI controllers.