基于扰动观测器的VIENNA整流器负载电流前馈控制

Load Current Feedforward Control of VIENNA Rectifier Based on Disturbance Observer

针对传统电压电流双闭环控制的VIENNA整流器在负载切换时直流输出电压波动幅值大、调节时间长的问题,基于扰动观测器的原理设计了一种负载前馈控制策略,利用扰动观测器对负载切换产生的扰动进行估算,将估计值前馈至电流内环的输入端,从而抑制电压幅值波动,缩短调节时间。与传统双闭环控制策略相比,加入扰动观测器降低了电压波动幅度,缩短了系统动态调节时间,提高了负载切换时的响应速度,增强了系统抗扰性。仿真验证了加入扰动观测器的可行性和有效性,实验结果表明,设计的扰动观测器,能减小负载切换时的电压波动幅度,缩短调节时间,有效地提高系统的性能。

Aiming at the problems of large fluctuation amplitude of DC output voltage and long regulation time during load switching of VIENNA rectifier with traditional voltage and current double closed-loop control,based on the principle of disturbance observer,a load feedforward control strategy is designed.The disturbance caused by load switching is estimated by disturbance observer,and the estimated value is feedforward to the input of the current inner loop,so as to suppress large voltage fluctuation and shorten the adjustment time.Compared with the traditional voltage and current double closed-loop control strategy,by adding disturbance observer,the voltage fluctuation amplitude is reduced,the dynamic regulation time of the system is shortened,the response speed during load switching is improved,and the disturbance immunity of the system is enhanced.The feasibility and effectiveness of the proposed control of adding disturbance observer are verified by simulation.The experimental results show that the designed disturbance observer can reduce the voltage fluctuation during load switching and shorten the regulation time,and effectively improve the performance of the system.