A DIRECT PHASE CONTROL SCHEME FOR UNITY POWER FACTOR THREE-PHASE BUCK TYPE RECTIFIER BASED ON SVPWM

摘要

This paper describes a direct phase control scheme for unity power factor three-phase Buck type rectifier modulated with space vector PWM method (SVPWM). The advantages of the developed system are low harmonic distortion in ac supply currents, nearly unity power factor over wide operating scope, easily realization. The theory analysis and modeling method are introduced first. Second, the control scheme and implementation based on Field Programmable Gate Array (FPGA) is put forward. Finally, the characteristics of the developed rectifier are tested from experiments. It is proved from simulation and experiments that the developed rectifier, using direct phase control scheme, has good dynamic and static performance though the PWM frequency is rather low.