Comparative Analysis of Voltage Control Techniques for Single Phase AC-AC Buck Converter

This paper analyzes the operation of a single phase (1-ϕ) AC-AC buck converter. In this direction, two modulation techniques have been discussed and compared for regulating the output voltage of the converter viz. carrier-based proportional integral (PI) voltage control technique and delta-sigma modulation (DSM) technique. The performance of single phase AC-AC buck converter is evaluated employing each modulation technique by conducting simulation studies in MATLAB/SIMULINK software. Subsequently, a comparison in terms of steady-state response, dynamic response and harmonic spectrum of source and load current is drawn when employing either modulation technique. It is observed that DSM technique outperforms the carrier-based proportional integral (PI) voltage control technique making it a better choice for modulation of AC chopper.