PERFORMANCE INVESTIGATIONS OF FUZZY CONTROLLED HIGH POWER FACTOR RECTIFIER

Abstract

The AC-DC conversion is increasingly used in a wide diversity of applications like power supply for microelectronics, household electric appliances, electronic ballast, battery charging, DC motor drives and power conversion, etc. The conventional line commutated rectifiers pollute the power supply which causes disturbances to other equipment connected to the same supply. They induce current harmonics into the supply resulting low power factor of the load. An extensive research work has been carried out to improve the power quality. The high power factor rectifiers are developed which draw nearly sinusoidal currents at a power factor near to unity. Current research has been focusing in the area of Pulse Width Modulated (PWM) rectifiers. In the present work, a three phase voltage source PWM rectifier is considered. A new sensor less control scheme, namely Virtual Flux based Direct Power Control (VFDPC), is applied to PWM rectifier. It has the advantages that it provides sinusoidal line current even with distorted supply. A fuzzy controlled VFDPC PWM rectifier is considered and the steady state and dynamic response is illustrated through the simulation study, carried out in the MATLAB/SIMULINK. Also, different hybrid fuzzy control techniques are examined through simulation. Finally, the experimental prototype of the considered PWM rectifier is developed and MOSFET switching is tested by generating gating pulses from the ICPDAS MATLAB embedded controller.