Characteristics of phase shift control of PWM controlled thyristor rectifier in current source GTO inverter system for induction motor drive

With the application of an energy rebound circuit for a pulse-width-modulation (PWM)-controlled thyristor rectifier, an improved current-source GTO inverter system capable of producing sinusoidal inputs and outputs has been proposed for high-frequency induction motor drives. The energy rebound circuit in the inverter is used not only to turn off the thyristors in the rectifier for applying PWM control techniques, but also to clamp the spike voltage produced in the inverter circuit. A simplified method and characteristics of phase shift control and DC link voltage control of PWM-controlled thyristor rectifiers with unity fundamental input power factor are presented. This method is applied to the regenerating operation of a PWM current source GTO inverter system to investigate the characteristics. The system is used to drive an eight-pole, 400 Hz, 5.5 kW induction motor. With the analytical and experimental results, characteristics of the motor drives are given.<>