变频电网三相有源电力滤波器重复控制策略

A repetitive control strategy for three-phase active power filters in variable-frequency power grid

中文关键词  有源电力滤波器  电流跟踪  重复控制  内模  变频电网

英文关键词  active power filters  current tracking  repetitive control  internal model  variable-frequency power grid

中文摘要

      为了在变频环境下, 提高三相并联型有源电力滤波器的电流跟踪性能和补偿效果, 提出了一种基于并联通 用内模, 具有频率自适应性的复合重复控制策略. 提出的并联通用内模能依据指令电流谐波成份的变化动态调节内 模的补偿范围和延迟时间, 并进一步将延迟时间缩短至同等补偿范围内模的一半, 显著提高了重复控制器动态性能 和适应能力. 内模中由电网频率变化引起的分数阶延时环节, 采用线性插值法近似, 使基于并联通用内模的重复控 制器具有频率自适应性. 采用插入式结构设计了复合重复控制系统. 详细分析了复合控制系统的稳定条件和收敛 性. 以飞机变频电网并联型有源电力滤波器系统为应用环境, 将提出的复合重复控制策略与其他控制策略进行了 对比. 仿真和实验结果验证了提出的复合重复控制策略的有效性和优越性.

英文摘要

      To improving the current tracking performance and compensation effect of three-phase shunt active power filter (APF) in variable-frequency environment, a frequency-adaptive repetitive control strategy based on shunt generic internal model was proposed. The proposed shunt generic internal model can adjust compensation range and delay time according to changes in harmonics of current reference and its delay time is 1/2 shorter than other internal models which have same compensation range. These features significantly enhance the dynamic performance and the adaptability of repetitive controller. Fractional-order delay links which caused by changes of grid frequency approximated by linear interpolation method. It makes the repetitive controller based on shunt generic internal model can adapt to frequency changes. The compound repetitive control system was designed in plug-in mode and the stability condition and convergence of compound system were analyzed in detail. The comparison of proposed control strategy with others was made in shunt active power filter of aircraft variable-frequency power grid. Simulation and experimental results were shown to confirm the validity and superiority of the proposed repetitive control strategy.