Design, Producing and Testing of 12-Step Three-Phase Voltage Source Inverter with Flexible Independent PWM Current Control for Brushless Direct Current Motor

Brushless motors are used in wide areas in the industrial and domestic applications owing to their superior advantages over other type electric motors such as induction and brushed direct current motors. Owing to fact that the brushless direct current motors and their drivers are cheaper and easier to design than drives of permanent magnet synchronous motors, brushless direct current motors are preferred a large application areas. But BLDC motor drivers are still run classical three-phase six- step inverter. Because of that the BLDC motors are run classical three-phase six-step inverter, the BLDC motor does not show its real dynamic performance. If BLDC motor is run via 12-step inverter, it gives a better dynamic performance than that of six-step inverter. The aim of this study, to manufacture 12-step inverter which controls phase currents using pulse width modulation (PWM) technique and to analyze the dynamic performance of BLDC motor running under purposed 12-step inverter. In the 12-step inverter, two or three transistors are on conduction mode at each time interval alternatively and in order to keep switching losses minimum only one transistor runs PWM mode in this study. The experimental results show that purposed flexible independent PWM 12-step inverter works perfectly and this proposed inverter provides the BLDC motor generating high dynamic performance than that of six-step one.