A feedback controlled PWM inverter based on delta-sigma modulation

A new control strategy for a pulse-width modulator inverter controlled by a synchronous delta-sigma modulator is presented. Two methods, based on delta-sigma modulation, are proposed for creating pulse-width modulated signals. The first method uses an over-sampled binary quantizer, while the second method employs a reference ramp signal along with an over-sampled binary quantizer. The benefits of both approaches are noise immunity and a simplified approach for filter design. Simulation results show good performance in the presence of noise. Additionally, the response time of a load filter is shown to be equal to the multiple time constant of a delta-sigma noise-shaping filter.