Comparative Study of Power Factor Correction Converters for Single Phase Half-Bridge Inverters

Half-bridge inverter is very suitable for singlephase on-line UPS applications because it offers very desirable features. These include fewer active switches, a common neutral connection – not requiring an isolation transformer, and sinusoidal input currents if a power factor correction (PFC) converter is used at the front end. This paper presents a comparative study of PFC converters for single-phase half-bridge UPS inverters. A traditional half-bridge converter and two recently introduced ac-dc/dc-dc boost converters are comparatively investigated for active switch count, voltage stresses on the switches, and capability of voltage balance control of the dc bus capacitors. Analytical and experimental results are included in this paper to illustrate performance differences among the converters in terms of input current harmonic distortion and energy efficiency.