链式D-STATCOM的鲁棒L_2性能准则设计

Robust L_2 Performance Criteria Design for Cascade D-STATCOM

为提高控制系统鲁棒性,提出一种链式静止同步补偿器(distribution static synchronous compensator,D-STATCOM)的鲁棒L2性能准则设计新方法。首先通过等效电路变化,将对链式D-STATCOM的控制电路模型转换为对单个H桥逆变单元的控制电路模型;在所建立的考虑干扰和参数摄动影响的单个H桥逆变单元控制电路模型基础上,通过对误差系统方程的等价变换,将参数摄动的影响转化为周期干扰的一部分;然后利用重复控制与无源性控制相结合的新方法实现链式D-STATCOM的鲁棒L2性能准则的设计。其中,重复控制对周期干扰进行补偿,无源性控制确保重复控制的收敛性和对控制目标的渐近跟踪,并抑制非周期干扰对控制效果的影响;通过给定指令电流,实现链式D-STATCOM的无功电流的控制和直流电压稳定的控制;利用H桥逆变单元之间的能量交换实现直流电压的均衡控制。仿真以及10 kV、5 Mvar工程实际应用结果表明,所提方法能够在实现无功电流控制的同时实现直流电压的稳定与均衡控制,且稳态特性好、动态响应快、算法实现简单、鲁棒性强,具有较强的工程实用价值。

In order to improve the control robustness, a novel robust L2 performance criteria design for cascade distribution static synchronous compensator （D-STATCOM） with disturbances and parametric perturbations was proposed. This paper built up single Hzbridge module for cascade D-STATCOM by equivalent circuit conversion, and then equivalent transform of error system of single H-bridge module was adopted so that the influence of parametric perturbations could be converted into part of the periodic disturbances. A novel algorithm by combination of repetitive control and passivity-based control was proposed to realize the robust L2 performance criteria design for cascade D-STATCOM. The reactive current and DC voltage stability control was realized by given instruction current. DC voltage balancing control was realized based on the power exchange among H-bridge modules. The validity and feasibility of this control strategy was verified by simulation results, and have been used on practical engineering of ＋5 Mvar, 10 kV D-STATCOM. Simulation and practical engineering application results show that this control strategy can completely realize the reactive current, DC voltage stability and balancing control of cascade D-STATCOM with excellent steady characteristic, fast transient response, easy implementation algorithm, strong robustness as well as important practical engineering value.