Certain investigations on brushless DC motor with DC DC converter topologies

Abstract

The exceptional performance high reliability ruggedness and wide range of speed control has made the brushless DC BLDC motor gain its importance over the last decade Its application area is also wider as it is well suited for all power ranges Medical analysers electric automotive and military applications are some of the key application areas of BLDC motor in addition to house hold applications motion control industrial automation ventilation and air conditioning applications The BLDC motors eliminates the sparking noise electro magnetic interference EMI and maintenance problems associated with conventional DC motors as these are synchronous motors with stator having three phase windings and a permanent magnets rotor with hall effect for position sensing These enable easier commutation of the electronic commutator VSI feeding the motor The drive is made simple whereas supplying the VSI with appropriate DC link voltage is vital to achieve desired control over the drive A DC link capacitor preceded by a diode bridge rectifier would serve the purpose But the problem is the high total harmonic distortion and injection of harmonics in the supply According to standard IEC 61000 3 2 these power quality indices are not acceptable Literature reports many isolated and non isolated power converters single stage which have minimal losses as the components are less in number Ozturk and Wu proposed a constant DC link BLDC drive using a boost topology whose speed is controlled by varying the VSI switching frequency of the BLDC drive newline