Application of predictive current control to a voltage source inverter

This paper presents a comparative study between the classical (Hysteresis and Proportional-Integral using PWM technique) and Predictive controllers for three-phase voltage source inverter. The hysteresis controller provides excellent dynamic performance, whereas the Proportional-Integral controller provides instantaneous current control and wave shaping, fixed inverter switching frequency resulting in only known harmonics. Predictive control method uses the discrete - time model of the system to predict the future value of the load current for all possible voltage vectors generated by the inverter. The voltage vector which minimizes the quality function is selected. The quality function used in this work evaluates the current error at the next sampling time. A comparison has been made in terms of THD level at the three phase load current. The simulation study has been carried out with the help of MATLAB Simulink environment and the performance of such controllers has been observed during load variations. The results shows that the predictive controls very effectively the load current and performs very well compared with the classical current controllers.