Finite-State Predictive Current Control of a Standalone DFIG-Based Wind Power Generation Systems: Simulation and Experimental Analysis

Abstract

This paper presents an improved stator voltage magnitude and frequency control for standalone doubly fed induction generators (DFIGs) based wind power generation systems (WPGSs). The proposed technique uses a simple finite-state predictive current control (FS-PCC). In this control method, the switching vector for the IGBT is selected to minimize the error between the reference value and the predicted value of the rotor current. Moreover, the discrete-time models of (DFIG) are needed to predict the future value of the rotor current for all possible voltage vectors generated by the rotor-side converter (RSC). Since the classic control methods in the literature use inner control loops and are based on pulse width modulation (PWM), this method does not require complex modulation stages and omits the current control loops, which reduces the control requirements. The main objective in a standalone DFIG system is to keep the stator voltage has constant in amplitude and frequency and equal to the reference value, regardless of the changes in rotor speed or load. The proposed control strategy was implemented through a 3 kW DFIG prototype platform-based dSPACE 1104 card. The simulation and experimental results show that the proposed FS-PCC offers excellent reference tracking with less total harmonic distortion (THD) in stator voltages and rotor currents.