Linear Quadratic Regulator-Based PI Control of a Non-Ideal Quadratic Boost PFC Converter for Low-Power Wind Energy Conversion Systems Supplying Uninterruptible DC Power

Abstract

DC–DC converters are efficient in providing a regulated power with power factor control in switch-mode power supplies and also in electric vehicle charging stations. The aim of this research work is to design an efficient DC–DC quadratic boost power factor correction converter for Wind Energy Conversion Systems (WECS) to provide uninterruptible DC power in case of one or two modules loss for low-power applications. The state-space model of the converter is derived using a state-space averaging technique through small signal modeling by considering the non-linearities. The reduced-order model is obtained using Routh-Pade's approximation method to reduce the complexity involved in the design of the controller parameters for the outer and inner loops. The outer voltage is regulated using an Internal Mode Control (IMC)-based proportional integral (PI) controller to overcome the effect of right-half plane zero (RHP) and three-phase currents are shaped by using three PI controllers. The three inner PI controllers for each phase are tuned using three methodologies like Zieglar Nichols, Skogestad and Linear Quadratic Regulator (LQR)-based PI control. The transient and steady-state performances of the closed-loop system are analyzed for variations in the load and set point using extensive computer-based simulation studies. The results reveal that the LQR-based PI controller show considerably better performance in terms of less settling time, overshoot, power factor and %THD, including parasitic parameters of the components.