DC Bus Voltage Control of Wind Power Inverter Based on First-Order LADRC

Abstract

The wind power grid-connected inverter system has the characteristics of non-linearity, strong coupling, and susceptibility to grid voltage fluctuations and non-linear loads. To obtain the ideal control effect, the improved linear active disturbance rejection controller (LADRC) controls the voltage outer loop. Firstly, the mathematical model of the wind power grid-connected inverter is analyzed, on this basis, a linear active disturbance rejection control based on the reduced-order linear extended state observer is designed, reduce the phase lag of the observer, improve the system’s disturbance observation accuracy; reference lead correction lag correction method, the observer gain is improved and connected in series to the total disturbance channel to reduce the noise amplification effect of the observer; through frequency domain response characteristic analysis, the results show that the improved LADRC has better disturbance rejection performance. The simulation results of various working conditions show that the improved method has better rapidity and immunity compared with traditional LADRC.

Keywords

• Grid inverter
• linear active disturbance rejection control
• linear extended state observer
• lead and lag link
• frequency domain analysis