基于LADRC与混合混沌序列RFPWM调制的DSTATCOM控制策略

摘要

配电网静止同步补偿器(Distribution Static Synchronous Compensator,DSTATCOM)是改善配电网系统电能质量的有效方法.针对级联多电平DSTATCOM中随机开关频率脉宽调制(Random Frequency Pulse Width Modulation,RFPWM)方式谐波含量较大,随机信号的选取和实现方式比较困难,提出一种新的基于混合混沌序列的RFPEM调制策略.同时针对该系统强耦合的特点,使用线性亡抗扰控制器(Linear Auto-disturbance Rejection Controller,LADRC)中的扩张状态观测器(Linear Extended States Observer,LESO)估计出系统内扰(包括模型的不确定项和耦合项)和外扰的实时作用并给予补偿,从而实现了d、q轴电流解耦的自抗扰控制.仿真结果表明:该综合控制策略在降低谐波的同时,具有更好的快速性和鲁棒性.%The DSTATCOM can improve power quality in power distribution system.Considering the high pulse harmonic content and difficulty in random selection and implementation of signals,a new RFPEM control strategy based on hybrid chaotic sequence was presented ; aiming at the characteristics of strong coupling of this system,the LESO in LADRC was used to estimate and compensate the real action of the system' s internal (including unmeasured and coupled state) and external unknown disturbances so as to realize auto-disturbance rejection control on d,q axis current decoupling.The simulation results prove this strategy's better rapidity and robustness and its capability in decreasing harmonic amplitude.