一种用于矩阵变换器的简化非线性自抗扰控制策略

矩阵变换器的电力直接变换特性使其输出侧性能极易受扰动影响,所以对矩阵变换器系统采取控制是非常必要的。由于矩阵变换器的非线性、多变量和参数时变性使其数学模型不能被确定,因此在内外部扰动不稳定的条件下,设计PI常数的单闭环控制系统并不那么成功。将一种与对象模型无关的自抗扰控制器应用于矩阵变换器系统,并且为解决自抗扰控制器控制模块的不光滑非线性函数导致矩阵变换器系统输出量谐波成分增大的问题,在自抗扰控制器的基础上,改进了自抗扰控制器模块的非线性函数并简化了其控制环。实验结果表明:当该自抗扰控制器用于矩阵变换器系统控制调节时,无论是在电网输入侧本身存在谐波污染的条件下,还是电网电压非正常工况条件下,其控制效果都优于PI控制。

A simplified nonlinear auto disturbance rejection control strategy for matrix converter

Matrix Converter (MC) has the characteristics of power direct conversion, which makes the performance of the output side easily affected by the disturbance, so it is very necessary to control the MC system. Due to the nonlinearity, multivariable and parameter variability of MC, the mathematical model can not be determined. Therefore, it is not so successful to design a single closed-loop control system with PI constant under the condition of unstable internal and external disturbances. An Auto Disturbance Rejection Controller (ADRC) which is independent of the object model is applied to the MC system. And in order to solve the problem that the non-smooth non-linear function of the ADRC control module causes the harmonic component of the MC output system is increased. On the basis of ADRC, the nonlinear function of the auto ADRC module is improved and its control loop is simplified. Experimental results show that when the ADRC is used for the MC system to control the adjustment, the control effect is superior to PI control both in the condition of harmonic pollution on the input side of the grid itself or under the condition of abnormal grid voltage. This work is supported by National Natural Science Foundation of China (No. U1404522) and National Key Research and Development Program of China (No. 2016YFC0600906).