Active disturbance rejection control of D-STATCOM under unbalanced voltage conditions

To improve the voltage quality of the power supply is an important function of the D-STATCOM. A novel voltage control strategy based on active-disturbance rejection control under unbalance voltage conditions is proposed in this paper. The active-disturbance rejection control for D-STATCOM is proposed to overcome the difficulty result from the nonlinear, multivariable and coupling characteristics of D-STATCOM and the uncertainty parameters of the model of D-STATCOM along with the uncertainty disturbance in the engineer application. The magnitude and unbalance degree of the voltage of Point of Common Coupling (PCC) can meet the national voltage supply standard through the use of controller structure with superposition of positive-negative voltage control loop. Furthermore the controller has excellent performance for example good adaptive and robust when the parameters changes and the disturbance occur. Under MATLAB/Simulink environment, the model of D-STATCOM system is built and the simulation result is given. The simulation results verified the correct and effectiveness of the control strategy proposed in this paper.