DC-Link Voltage Research of Photovoltaic Grid-Connected Inverter Using Improved Active Disturbance Rejection Control

In this paper, a robust DC-link voltage control scheme is proposed to improve the tolerance of photovoltaic (PV) grid-connected inverter disturbances. The sensitive characteristic complicates dynamics system and limits its overall performance, especially when uncertain disturbances are considered. To cope with issue, controller based on linear active disturbance rejection (LADRC) designed. By exploring principle deviation regulation, an improved extended state observer (LESO) established ensure that total can be estimated in relatively timely manner. error feedback (LSEF) law generated compensate for disturbance, which reduces plant approximate canonical cascaded double integrator. stability capability LADRC further analyzed frequency domain. Finally, theoretical analysis experimental results confirm feasibility scheme.