三电平有源电力滤波器的无差拍控制研究

对三电平主电路拓扑结构的并联型有源电力滤波器进行研究,首先介绍了其谐波电流检测方法、三电平主电路数学模型以及无差拍控制策略。针对三相三线制有源电力滤波器,根据所建立的主电路基于abc三相和d-q旋转坐标系下的数学模型,详细阐述了无差拍控制的原理、主电路的离散化模型。并分别提出非线性负载稳定和突变两种运行情况下谐波电流的预测算法。基于MATLAB/Simulink系统仿真分析结果表明,所提出的无差拍控制方法能很好地保证控制系统的精度和动态响应的速度。

Research on Deadbeat Control of Three-level Active Power Filter

In this paper, deadbeat control is proposed for a shunt active power filter (APF) based on three-level inverter to reduce line current harmonics. Firstly, the working principles of harmonics detection and the mathematical models of the 3-phase 3-wire three-level tri-leg APF are introduced in details. Based on the above models of state equations, the work brings us to the conclusion that the predictive harmonic current value of one sampling period ahead is the most important step in deadbeat control strategy. Moreover, an effective method of harmonic current prediction is presented for nonlinear loads both in steady and dynamic state operation. The experimental results show that the compensating ability of this APF is high in accuracy and responsiveness.