基于二重积分滑模控制的光伏并网系统

Photovoltaic grid-connected system based on double integral sliding mode control

为改善光伏并网逆变器的动态特性,根据逆变器数学模型,利用二重积分滑模控制,设计两级结构的单相光伏并网控制系统。前级利用PI控制完成升压稳压,后级通过滑模控制实现逆变并网,完成滑动模态在逆变系统的理论推导。在此基础上进行仿真研究,并与PI控制系统进行比较,其结果表明所提出的控制策略是正确的,并且具有实现简单的特点。

In order to improve the dynamic characteristic of PV grid-connected inverter,a single-phase PV grid-connected inverter system with two-stage structure was designed according to the mathematical model of the inverter and double integral sliding mode control.The PI control is used in the pre-stage to achieve the voltage boost and voltage stabilization,the sliding mode control is used in the backward-stage to realize the grid connection of the inverter.The theoretical derivation of the sliding mode in the inverter system is performed.The simulation study is carried out on the above basis.The proposed control system is compared with PI control system.The results show that the proposed control strategy is correct,and has the characteristic of easy implementation.