LCL滤波器的链式STATCOM容错控制策略研究

Study on fault-tolerant control for cascaded STATCOM with LCL filter

为提高LCL滤波器的6 k V/8级联STATCOM运行可靠性,基于对装置故障准确诊断的前提下,通过调整链式STATCOM的软硬件结构来保证装置在故障情况下稳定可靠的运行能力。采用带一级冗余的硬件冗余方法结合解析冗余方法解决装置的容错控制问题,将需要进行容错控制处理的相间/相内电容电压平衡控制策略以及PWM调制策略纳入控制框架,当故障发生后通过封锁驱动脉冲和旁路机构将故障模块同主电路隔离,最终达到装置的故障诊断与容错控制的无缝结合。仿真与实验结果证明,通过容错控制策略装置具有良好的动态补偿效果,容错控制响应迅速。

In order to improve the reliability of 6 k V cascaded STATCOM with LCL filter,the reliability and safety of the system could be improved by using the software tolerance and hardware techniques together. The reliable and stable operation capability could be ensured by reconfiguring hardware structures and software with fault-tolerant control strategies. To realize seamless fusion between fault diagnosis and fault-tolerant control,phase inside voltage balance control and phase to phase voltage balance control strategy of the capacitor and PWM control strategy with fault-tolerant control function were brought into the control framework. The simulation and experiment demonstrate that the platform has good dynamic compensation effects,accurate diagnostic ability,and fine fault-tolerant control performance.