This paper presents a power factor correction (PFC) based bridgeless-Luo (BL-Luo) converter fed brushless DC (BLDC) motor drive. A single voltage sensor is used for the speed control of BLDC motor and PFC at AC mains. The voltage follower control is used for a BL-Luo converter operating in discontinuous inductor current mode (DICM). The speed of the BLDC motor is controlled by an approach of variable DC link voltage, which allows a low frequency switching of voltage source inverter (VSI) for electronic commutation of BLDC motor; thus offers reduced switching losses. The proposed BLDC motor drive is designed to operate over a wide range of speed control with an improved power quality at AC mains. The power quality indices thus obtained are under the recommended limits of IEC 61000-3-2. The performance of the proposed drive is validated with test results obtained on a developed prototype of the drive.
- Bridgeless Luo Converter
- Brushless DC motor
- Power Factor Correction
- Power Quality
- Voltage Source Inverter
Fig. 1. Proposed PFC BL-Luo Converter fed BLDC motor drive.
EXPECTED SIMULATION RESULTS:
Fig. 2. Test results of proposed BLDC motor drive (a) At rated load torque on BLDC motor with Vdc=50V and Vs=220V, (b) At rated load torque on BLDC motor with Vdc=200V and Vs=220V
Fig. 3. Test results of proposed BLDC motor drive showing (a) iLi1, iLo1, VC1 with Vs, (b) PFC converter’s switch voltage and current at rated load torque on BLDC motor (c) Enlarged waveforms of PFC converter’s switch voltage and current.
Fig. 4. Test results of proposed BLDC motor drive showing dynamic performance (a) during starting at 50V, (b) during change in DC link voltage from 100V to 150V, (c) during change in supply voltage from 250 to 180V.
A PFC based BL-Luo converter fed BLDC motor drive has been proposed for wide range of speeds and supply voltages. A single voltage sensor based speed control of BLDC motor using a concept of variable DC link voltage has been used. The PFC BL-Luo converter has been designed to operate in DICM and to act as an inherent power factor preregulator. An electronic commutation of the BLDC motor has been used which utilizes a low frequency operation of VSI for reduced switching losses. The proposed BLDC motor drive has been designed and its performance is simulated in MATLAB/Simulink environment for achieving an improved power quality over wide range of speed control. Finally, the performance of proposed drive has been verified experimentally on a developed hardware prototype. A satisfactory performance of proposed drive has been achieved and is a recommended solution for low power applications.
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