Rectifier Stage Control Strategy for Solid State Transformer Based on Sliding Mode Active Disturbance Rejection

Abstract

Solid-state transformer (SST) is the core equipment of energy router in Energy Internet. As distributed generation units are often in multivariable, strong coupling and violent unknown disturbance, these seriously affect the stable operation of the system. To solve this problem, a sliding mode active disturbance rejection controller (SMADRC) is designed for solid-state transformer rectifier stage. The state variables observed by the linear extended state observer (LESO) are used for feedforward compensation adjustment in the sliding mode controller (SMC) to reduces random fluctuation of bus voltage caused by disturbance. The system is verified by the simulation platform, and the results show that the dynamic performance and grid-connection quality of the system are significantly improved by the sliding mode ADRC.