针对LCL滤波器网侧电流瞬时值反馈控制难以闭环稳定的问题,提出一种基于LCL滤波器网侧电流反馈的以比例积分(PI)控制器、二阶低通滤波器(LPF)作为电流控制内环,结合重复控制以及对应校正环节作为电流外环的链式静止无功补偿器(STATCOM)电流跟踪控制策略,通过控制内环中二阶LPF及PI控制器的设计解决LCL滤波器的稳定阻尼控制与基波无功电流的无静差跟踪控制,结合重复控制电流外环完成链式STATCOM对谐波电流的跟踪控制,兼顾了装置对补偿带宽内电流跟踪控制的稳态精度与动态性能。仿真与实验验证了所提控制策略的正确性。
A current track control method of cascaded static var compensation (STATCOM) which based on LCL filter grid side current feedback using proportion integral(PI) controller and second order low pass fiher(LPF) as inner loop and repetitive control as outer loop is proposed.The steady damp control of LCL filter and floating control of fundermental wave reactive power current are solved by controlling the second order ILPF and PI controller of the inner loop, ensuring both fast dynamic response and small steady-state error for current track and compensation in the bandwidth of cascaded STATCOM.Simulation and experiment validate the feasibility of the method.