PERFORMANCE OF PWM-CONTROLLED THYRISTOR RECTIFIER OPERATING AT UNITY FUNDAMENTAL POWER-FACTOR IN PWM CURRENT SOURCE GTO INVERTER SYSTEM FORINDUCTION-MOTOR DRIVES

The performance of PWM-controlled thyristor rectifier operating at uni ty fundamental input power factor in PWM current source GTO inverter s ystem for high speed high horse power induction motor drive is analyze d and found out in this paper. With the application of an energy rebou nd circuit in the dc link of the inverter for PWM control of the thyri stor rectifier, a PWM control current source GTO inverter has been pro posed. The principles and fundamental behavior of this inverter also h ave been investigated. A prototype unit of the PWM-controlled current source GTO inverter system is used to drive an 8 pole, 400 Hz, 5.5 kW three-phase induction motor. With the analytical and experimental resu lts, the performance of the dc voltage control of the PWM-controlled t hyristor rectifier for various values of the number of pulses for a ha lf period of the supply frequency is also given in detail in this pape r.