基于李亚普诺夫方法的有源电力滤波器电流稳定控制

Lyapunov-Based Current Stability Control Method of Active Power Filter

为确保负载和系统参数变化时有源电力滤波器的稳定运行,提出一种基于李亚普诺夫理论的控制方法。以补偿电流和直流侧电压的跟踪误差作为状态向量和输出向量,逆变器开关通断的占空比为输入向量来建立状态方程。用状态向量构建李亚普诺夫函数,根据稳定条件确定输入向量,保证控制过程的收敛性。考虑到时变负载会引起直流侧电压较大的波动,用直流侧电压的平均值来建立状态向量。分析系统参数与性能之间的关系,得到参数的取值范围。通过Matlab/Simulink进行整流负载和直流调速负载仿真实验,在负载时变和系统参数变化的情况下,有源电力滤波器运行稳定,证明该方法的有效性。

A control method based on Lyapunov theory is proposed in this paper in the purpose of ensure the stability operation of the active power filter （APF） under the influence of varying load and system parameters. State equations are constructed by using the tracking error of the compensate current and direct current （DC） capacitor voltage as state vectors and output vectors while the duty ratio of the voltage source inverter （VSI） switching as the input vector. With the state vectors constructing the energetic like Lyapunov function, the input vectors could be determined and thus adapt to the variation, ensuring the convergence of the control process. Considering that the time-varying load may cause significant fluctuations in DC capacitor voltage, an average value of DC capacitor voltage is used in calculation of the control output. The relationship between system parameters and performance is then analyzed to determine the value ranges of system parameters. Rectifier load and DC speed regulating system are tested via Matlab/Simulink. As the results show, the proposed method operates steadily under the conditions of varying load and system parameters, which thus verifies the utility and reliability of the proposed control method.