Fuzzy Logic Based Sensorless Control of Three-Phase Brushless DC Motor Using Virtual Instrumentation

This paper presents a novel sensorless control of permanent magnet brushless DC motor (PMBLDC) using fuzzy controller. It is based on “indirect position sensing” method. The postion detection can be derived from the voltage and current waveforms. Such position information is derived from the line voltage difference measured at the terminals of the motor instead of back-electromagnetive force to eliminate the harmonics. For precise control and to get desired performance the motor is controlled using fuzzy controller. This Controller is virtually implemented in LABVIEW software of virtual Instrumentation. The waveforms also obtained easily from the front panel of LABVIEW. Because of the virtual fuzzy controller, there is no need of any separate processor like microcontroller or FPGA or DSP to implement the fuzzy logic. So this drive system has more advantage than the conventional sensorless control. As a result the proposed drive system is cost effective , more flexible and robust.