基于改进型滑模控制的光伏并网系统

为解决滑模控制中的抖振问题, 针对光伏并网控制系统, 设计了基于改进型滑模变结构的三相电压型逆 变器。 该方法首先找出准确的滑模切换函数, 推导了其切换函数的存在性; 然后对所得的滑模切换函数进行 “扩大冶, 通过自适应控制得到需增加的距离。 同时经 Matlab 平台搭建仿真模型进行实验验证, 对比分析滑模 变结构控制策略改进前后的瞬态性能。 结果表明, 改进后系统的输出电压较平稳, 总谐波失真降低到 0. 62%, 很好地解决了滑模控制中的抖振问题。

Photovoltaic Grid Connected System Based on Improved Sliding Mode Control

In order to solve the chattering problem of sliding mode control,a three-phase voltage inverter based on improved sliding mode variable structure is designed for photovoltaic grid-connected control system.The existence of the switching function is deduced by using the sliding mode switching function, the obtained sliding mode switching function is"expanded",and the incremental distance is obtained through adaptive control to stabilize the output voltage,the total harmonic distortion is reduced,and the sliding mode control of the chattering problem is solved.The theory analyzes the transient performance of sliding mode variable structure control strategy contrastively in the Matlab platform.The result indicates that the output voltage improved is more stable,the total harmonic distortion is reduced to below 0.62%and the problem of chattering in sliding mode control is solved.