Improved Gain Single-Phase Buck-Boost PFC With Wide Output Voltage Range for Universal Input EV Applications

This article introduces an improved gain buck-boost (IGBB) power factor correction (PFC) ac–dc converter for on-board charging (OBC) of electric vehicles (EVs). The proposed converter facilitates efficient charging across a power range of 1–3.3 kW. In conventional buck-boost PFCs characterized by a high gain and a duty ratio approaching unity, substantial voltage gain optimizes the configuration for specific operational conditions. However, the above-mentioned issue is resolved in the proposed configuration without additional components. The proposed converter can perform buck and boost operations with a duty ratio not exceeding 0.5, thereby reducing the magnitude of conduction losses and improving efficiency. Finally, a 1 kW down-scaled laboratory prototype is developed and tested to confirm its validity and robustness. It demonstrates a superior performance across a wide output voltage range (48–400 V) for a universal input range from 85 to 265 V ac. The results demonstrate its ability to keep the input current’s total harmonic distortion (THD) within specified limits.