基于GPI观测器的Buck型变换器趋近律控制

A Reaching Law Control for Buck Converter Based on GPI Observers

针对Buck型变换器中存在的匹配和非匹配扰动,提出一种基于广义比例积分观测器(GPIO)和增强型变速趋近律的控制方法;首先,设计广义比例积分观测器来估计匹配和非匹配扰动,并将估计值引入控制器中进行前馈补偿;同时,构造了基于双曲正切型函数的变速趋近律,可以缩短系统状态的到达时间,并减小在滑动阶段的抖振现象,并与广义比例积分观测器结合,使系统具有良好的抗干扰性能和跟踪性能;最后,证明了观测器的收敛性和闭环控制系统的稳定性,并通过仿真验证该方法可以有效地抑制扰动带来的影响,提高整个系统的抗干扰性能。

Aiming at the matched and mismatched disturbances in Buck converters,a method based on generalized proportional integral observers(GPIO)and variable rate reaching law control method is proposed.First,design a generalized proportional integral observer to estimate matched and mismatched disturbances,and the estimated value is introduced into the controller for feedforward compensation.Then,a variable speed reaching law based on the hyperbolic tangent function is constructed,which can shorten the arrival time of the system and reduce the chattering phenomenon in the sliding phase.Combined with generalized proportional integral observer,it has good anti-interference performance and tracking performance.Finally,it proves the convergence of the observer and the stability of the closed-loop control system.It is verified by simulation that this method can effectively suppress the influence of disturbance,and improve the anti-interference performance of the entire system.