Sensorless Single-Switch PFC Converter Fed Brushless Direct Current Motor Ceiling Fan
Amit Kumar, Utkarsh Sharma, Bhim Singh
Abstract
This work deals with the reduction in total harmonics distortion, power input, and a supply power factor correction (PFC) of permanent-magnet brushless direct-current motor (PMBLDCM) ceiling fan (CF) to get reduced bills for the consumers. To address these supply power-quality issues in the existing PMBLDCM-CF, a single-stage, single-switch boost-flyback power-factor-correction-converter (S4BF-PFCC) is employed at the front-end. The front-end PFCC is designed in discontinuous conduction mode, which offers inherent supply PFC. The high-frequency-transformer (HFT) auxiliary-voltage is utilized as a feedback to get the controlled PFCC voltage output <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(V_{DC})$ </tex-math></inline-formula> , and with this controlled <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{DC}$ </tex-math></inline-formula> , CF speed is controlled. This method eliminates the required DC-link sensor or sensing circuitry. Moreover, the back-EMF sensorless-control is used to eliminate the Hall sensors and their auxiliary supply. The speed control with a variable output voltage of front-end PFCC allows an inverter to work at a commutation frequency, which offers low switching losses and improves CF efficiency. This CF system is modelled and simulated in MATLAB/Simulink. Its simulation and test results are compared to validate the design. The supply current harmonics distortion of CF meets the IEC standard 61000-3-2.