Nonlinear control of DC-bus voltage and power for Voltage Source Inverter

This paper presents a nonlinear control of dc-bus voltage, active and reactive powers for wind power grid connected Voltage Source Inverter (VSI). The controller exploits the backstepping scheme to calculate the required inverter´s control to eliminate the instantaneous errors of dc-link voltage, active and reactive powers. The nonlinear control can increase the system effectiveness and realize voltage source control frequency. The proposed control laws are derived from the Lyapunov approach which is well suited for this nonlinear circuit. Control analysis and simulations results are obtained using Matlab/Simulink. These results show how the backstepping control laws provides an efficient control design in comparison with conventional linear control for tracking references and regulations in order to improve dc-link voltage stability. The active power and reactive power are regulated independently, and good unity power factor correction (PFC) is achieved.