基于自适应滤波算法的整流器电流预测控制

应用数字芯片控制的三相PWM整流器由于电流采样延时和计算延时而造成系统稳定裕度变小、动态性能变差。为解决这个问题,提出了应用变步长自适应滤波算法的电流预测控制。首先,以三相PWM整流器数学模型为基础,分析了数字延时对系统性能的影响。其次,介绍了变步长自适应滤波算法的基本原理,并将此原理应用于电流信号预测。再次,给出基于上述算法的三相PWM整流器电流预测控制的结构框图。仿真和实验结果表明,由于采用了电流预测控制,消除了延时的影响,使电流环稳定范围增大,同时具有更好的动态性能。

Current Predictive Control of Rectifier Based on Adaptive Filter Algorithm

Because of current sampling delay and calculation delay,three-phase PWM rectifier controlled by digital processing chip has low stability margin and bad dynamic performance.To solve this problem,the current predictive control method using variable step-size adaptive filter algorithm was given.Firstly,analyzed the effect of digital delay on system performance based on PWM rectifier math model.Secondly,introduced the basic principle of variable step-size adaptive filter algorithm and applied the prinliple in the current signal prediction.Thirdly,presented the structure diagram of current predictive control of three-phase PWM rectifier that is based on the algorithm above.Simulation and experimental results prove that the stability field becomes greater and dynamic performance better thanks to eliminating the delay′s effect by using current predictive control.