基于非线性状态观测器的直流降压变换器自抗扰控制  

Active disturbance rejection control method ofDC buck converter based on nonlinear state observer

作　　者：罗琳 李生权 王书旺 李娟 LUO Lin;LI Shengquan;WANG Shuwang;LI Juan(School of Electrical,Energy and Power Engineering,Yangzhou University,Yangzhou 225127,China)

机构地区：[1]扬州大学电气与能源动力工程学院,江苏扬州225127

出　　处：《扬州大学学报（自然科学版）》2021年第4期38-43,57,共7页Journal of Yangzhou University：Natural Science Edition

基　　金：国家自然科学基金资助项目(6190332);可再生能源电力系统国家重点实验室资助项目(LAPS19003);江苏省六大人才高峰资助项目;扬州市优秀青年基金资助项目(YZ2017099);江苏省研究生研究与实践创新项目(SJCX20_0890)

摘　　要：针对脉宽调制型DC-DC降压变换器的负载变化、输入电压波动和系统动态不确定性等内外干扰,以及线性观测器的大增益效应所产生的峰值现象和低精度等问题,提出一种基于非线性扩张状态观测器的自抗扰控制方法.首先,根据直流降压变换器的输出电压与期望电压之间的误差建立系统的数学模型,对DC-DC降压变换器的不匹配干扰进行微分处理转换为均匀匹配型系统干扰;其次,利用非线性扩张状态观测器对输入电压、负载变化和建模误差等内外总干扰进行估计,并通过前馈通道进行补偿,再复合反馈通道的PD方法实时控制整个系统;最后,在MATLAB/Simulink环境中搭建仿真模型,与传统的线性自抗扰控制进行对比验证.结果表明,该直流降压变换器自抗扰控制方法不仅能以较小的增益获得更佳的跟踪和稳态性能,而且可增强系统的抗干扰能力和鲁棒性.Considering the internal and external disturbances such as load variation,input voltage fluctuation and dynamic uncertainty of the pulse width modulation based DC-DC buck converter,as well as the peak phenomenon and low precision caused by the large gain effect of linear observer,an active disturbance rejection control(ADRC)method based on nonlinear extended state observer(NESO)is proposed in this paper.Firstly,a mathematical model is established according to the error between the actual output voltage and the expected voltage of the DC-DC buck converter,since the mismatched disturbance of the DC-DC buck converter can be converted into a uniformly matched disturbance.Secondly,the nonlinear extended state observer is introduced to estimate the total internal and external disturbances such as input voltage,load variation and modeling error,and compensation is carried out through the feedforward channel,and then the feedback channel PD controller is used to guarantee the stability of the whole system.Finally,a simulation model is built in MATLAB/Simulink to verify the effectiveness and superiority of the proposed method by contrasting with the traditional linear active disturbance control method.The simulation results show that the proposed NESO-based control method can not only obtain better tracking and steady-state performance with small gain,but also enhance anti-disturbance ability and the system robustness.

关 键 词：DC-DC降压变换器 非线性扩张状态观测器 自抗扰控制 匹配/不匹配干扰 

分 类 号：TP273.3[自动化与计算机技术—检测技术与自动化装置]