基于改进型观测器的三相LCL型PWM整流器控制

LCL-type PWM Rectifier Control System Based on Improved State Observer

基于LCL滤波器完全可观、可控的特性,在系统离散状态空间模型基础上设计了比例积分(PI)全状态反馈控制。此外,针对额外增加的传感器,引入状态观测器。理论分析了传统Luenberger状态观测器的观测误差,建立引入机侧电压噪声的偏差模型,定量分析了噪声对观测输出的影响,并提出通过积分项的引入消除观测误差,进而提出改进型的积分补偿型观测器。在3 kW实验样机上进行了对比实验,验证了改进型观测器有利于改善系统的并网波形。

Because of the fully observable and controllable characteristics of LCL filter,the proportional integral（PI） full state feedback control is designed based on the discrete state space model.For the additional increase of sensors,the state observer is introduced.The observation error of Luenberger state observer is analyzed and the bias model is established to analyze the influence of the noise.Improved observer is proposed, through the introduction of integral term which trying to eliminate the observation error.A comparative experiment is carried out on the 3 kW experimental prototype which proves that the improved observer is helpful to improve the grid-connected waveform of the system.