Analysis of a PWM voltage source inverter with PI controller under non-ideal conditions

Apart from the traditional pulse-width modulation (PWM) or SPWM voltage source inverters (VSI), the proposed VSI with a Proportional integral current controller (PI VSI) offers superiority. They include instantaneous current control and wave shaping, fixed inverter switching frequency independent of the output frequency resulting in only known harmonics, and free-running carrier operation. A modeling approach to proposed PI VSI is introduced. A design example of the VSI power circuitry is presented. The PI controller design is discussed. Finally the VSI load current is verified for harmonic contents and instantaneous current control capabilities, under normal, unbalanced, load outage and load short-circuit conditions.