This thesis presents the steady-state analysis of an induction motor drive fed by a pulse-width-modulated current source inverter (PWM CSI). This PWM CSI uses self-commutated switching devices and requires a three-phase capacitor at its terminals to filter out current harmonics. The inverter output current and voltage, therefore, can be nearly sinusoidal.

In this thesis, a PWM switching pattern specially designed for large motor drives with a low switching frequency is proposed. It combines the trapezoidal pulse width modulation and the selected harmonic elimination techniques to provide an effective means for harmonic control. A simple algorithm for steady-state simulation is formulated based on a motor circuit model. The state equations of the drive system can be easily derived by using this model. Two resonance phenomena exist in this drive system due to the parallel connection of the capacitor and the induction motor. These resonances may produce excessively high voltage, power losses and torque pulsation. Strategies to suppress these resonances are developed. Furthermore, a control strategy which can eliminate the use of a tachometer for the PWM CSI induction motor drive is developed.

Results obtained from analysis are verified by experiments.