This reduces the switching losses in VSI due to the low frequency operation of VSI for the electronic commutation of the BLDC motor. The speed control of BLDC motor is achieved by the dc link voltage control of VSI using a BL buckвЂ“boost converter. The parameters of the BLbuckвЂ“boost converter are designed such that it operates in discontinuous inductor current mode (DICM) to achieve an inherent power factor correction at ac mains. The bridgeless (BL) buckвЂ“boost converter-fed brushless direct current (BLDC) motor drive is used to improve the power Factor Correction. A high frequency MOSFET of suitable rating is used in the front end converter for its high frequency operation whereas an IGBTвЂ™s (Insulated Gate Bipolar Transistor) are used in the VSI for low frequency operation. A blind startup is used for starting the BLDC motor. A sensor less approach is used to detect the rotor position for electronic commutation. Switch of the Sepic converter is to be operated at high switching frequency for effective control and small size of components like inductors. In this project, the front end Sepic DC-DC converter maintains the DC link voltage to a set reference value. These BLDC motors are not limited to household applications, but these are suitable for other applications such as medical equipment, transportation, HVAC, motion control, and many industrial tools. The use of the brushless direct current (BLDC) motor is becoming very common due to features of high efficiency, high flux density per unit volume, low maintenance requirements, and low electromagnetic-interference problems. A MATLAB/ Simulink environment is used to simulate the developed model to achieve a wide range of speed control with high PF (Power Factor) and improved PQ (Power Quality) at the supply.

A sensor less control of BLDC motor is used to eliminate the requirement of Hall Effect position sensors. The DC link capacitor of the Sepic converter is followed by a VSI which is feeding a BLDC motor. The Sepic converter is working as a frontend converter operating in DICM (Discontinuous Inductor Current Mode) and thus using a voltage follower approach. Voltage of a DC link capacitor of Sepic converter is controlled to achieve the speed control of BLDC motor.

A novel PFC (Power Factor Corrected) Converter using SEPIC DC-DC converter feeding a BLDC (Brush Less DC) motor drive using a single voltage sensor is proposed.

Fuzzy logic matlab simulink