光伏多功能并网逆变器迭代SMC+LADRC电流内环控制策略研究

Iterative SMC+LADRC Current Inner Loop Control Strategy of Photovoltaic Multi-Function Grid Connected Inverter

针对LCL型三电平光伏多功能并网逆变器存在谐波谐振、系统抗干扰能力弱、电流跟踪精度低以及新型配电系统下负荷负载的多变复杂性等问题,设计了一种迭代滑模控制与三阶线性自抗扰控制相结合的电流内环综合控制器。首先,建立d-q坐标系下LCL型三电平逆变器数学模型;其次,设计迭代滑模控制与线性自抗扰控制电流内环控制器,并分析了综合控制器的传递函数、响应速度、跟踪精度和谐波谐振抑制能力;最后,通过仿真验证了文中所提综合控制策略可较好地抑制谐振和电流谐波畸变现象,且电流输出波形质量良好。

The LCL type three-level photovoltaic multi-function grid connected inverter has the problems of harmonic resonance,weak system anti-interference ability,low current tracking accuracy,load variable complexity in new distribution system.A current inner loop integrated controller combining iterative sliding mode control and third-order linear active disturbance rejection control is designed.Firstly,the mathematical model of LCL three-level inverter in the d-q coordinate system is established;Secondly,an iterative sliding mode control and linear active disturbance rejection control current inner loop controller are designed,and the transfer function,response speed,tracking accuracy,and harmonic resonance suppression capabilities of the integrated controller are analyzed.Finally,simulation results show that the proposed comprehensive control strategy can effectively suppress resonance and current harmonic distortion,has good current output waveform quality.