Fuzzy-Improved Linear Active Disturbance Rejection Control of Solid State Transformer Inverter Stage

The inverter stage of solid state transformer is a nonlinear, time-varying and multi-variable system. In order to improve the performance of solid state transformer, a Fuzzy-Improved Linear Active Disturbance Rejection Control (Fuzzy-ILADRC) is proposed. For the three-phase AC voltage control problem of the load side, firstly, the first-order differential term is introduced into the linear state error feedback (LSEF) to compensate the steady state error. Secondly, the fuzzy control is combined with the improved linear state error feedback to realize the on-line self-adjustment of the controller parameters. Finally, MATLAB&SIMULINK simulation platform is used to simulate and verify Fuzzy-ILADRC control solid-state transformer inverter stage. The simulation results of multiple working conditions show that, compared with PI, the improved method has higher steady-state accuracy of output voltage, lower total harmonic distortion rate of voltage, and superior anti-interference ability.