有源滤波器的改进开闭环迭代电流控制

Improved open-closed-loop iterative control for active power filter

开环迭代控制已被应用于滤波器系统,但在利用谐波电流误差信息方面存在着不足,影响了滤波器的性能。为了改善滤波器滤波效果,本文提出一种改进的开闭环迭代电流控制方法,增强了系统的稳定性,另外得到了该方法在滤波器中应用的收敛性条件分析。开闭环迭代电流控制器的当前输出信号由前一次迭代时的输出信号及电流误差和当前次迭代时电流误差信号组合而成,其充分利用了谐波电流误差信息,修正了开环迭代控制算法在滤波器中应用的不足。所提开闭环迭代控制器结构简单,采用了Hebb学习规则自适应调节控制器的参数,优化了控制器性能,系统具备较好的抑制电网谐波的能力,电流稳态控制误差较小。最后,仿真与实验结果验证了方法的可行性和有效性。

Open-loop iterative control has been used in filter system, but it has the shortcomings such as inadequate use harmonic current error information, which affects the filter performance. In order to improve filtering effect of active power filter, the paper proposes an improved open-closed-loop iterative current control method, which enhances the system stability. The convergence condition of the proposed algorithm used in filter system is obtained.The control output of proposed current controller is composed of the control output as well as current error of previ- ous iteration and the current error signal of present iteration. The harmonic current error signal can be used in the proposed open-closed-loop control adequately, which corrects the shortcoming of open-loop iterative control. Hebb rules are used to optimize the controller parameters, and the optimal system performance is obtained. The system possesses good ability of suppressing harmonic current, and the steady-state error is small. The simulation and experimental results have shown the feasibility and effectiveness of the proposed method.