A high performance current source inverter

A modified PWM (pulse width modulated) current source inverter (CSI) that can operate with varying modulation indices (including low modulation indices) is presented. Any standard VSI (voltage source inverter) PWM pattern can be used with this inverter. This feature is obtained without compromising the converter system efficiency and power factor, and at the cost of only one auxiliary switch. The added degree of freedom obtained through modulation index control allows instantaneous control of output current and results in a high-performance inverter system. Inverter steady-state performance equations have been derived, as well as design equations and guidelines. The feasibility and performance of the CSI are verified by simulation and experimental implementation on a 5 kVA system. >