AC-DC PFC Converter Fed BLDCM Ceiling Fan

An AC-DC power factor corrected converter (PFCC) fed brushless direct current motor (BLDCM) fan is presented with high-frequency transformer isolation. A front-end PFCC in series with a VSI (Voltage Source Inverter) is utilized to drive the BLDCM fan with enhanced PQI (Power Quality Indices) at the supply RMS voltage. The turn ratio of the isolation transformer is considered in such a way that the switch stress is minimum. The PFCC is designed in discontinuous conduction mode (DCM) of operation to get the natural power factor correction at the supply side. An auxiliary voltage of the HFT is utilized to handle the supply voltage fluctuation and to control the PFCC output voltage. The line frequency switching minimizes the inverter losses due to switching. The prime objective is to design the ceiling fan without using any sensor, low harmonics distortion, compact size, and minimum losses. It reduces the fan cost. Simulated results are shown to validate the design and performance of the fan system.