Analysis of the Effects of Three Various Current Control Methods on BLDC Motors

Brushless direct current motors are very popular motors in a wide application area thanks to their superiorfeatures. Brushless motors are the most preferred motors in applications such as domestic, robotics, officemachines, medical, military and space applications, unmanned aerial vehicles applications because they meetthe special requirements of these applications. Brushless direct current (BLDC) motors have high volume torqueratio, high efficiency, fast dynamic response; they offer linear torque/speed characteristics. Speed control ofBLDC motors achieves by implementing pulse width modulation (PWM) technique. Various PWM controlmethods are put in to use for controlling of BLDC motor speed. These PWM methods have some certainadvantages and disadvantages. In this study, three current control PWM methods which are mostly used inpractices are examined. These are full conduction mode, independent and complementary PWM methods. Forthis purpose, three BLDC motor pre-drivers have been designed and manufactured and the effects of these threedrivers on the BLDC motor have been examined. It has been found that complementary PWM mode has givento BLDC motor fast dynamic response. Full conduction mode has drawn higher dc link current from DC powersupply. Independent PWM method performance is very close to complementary PWM method.