62 / 2017-01-31 13:13:47

Design of Sensorless Speed Control of BLDC Motor Using Pole Placement Technique

1. Brushless Direct Current motor (BLDC) 2. State Feedback Controller (SFC) 3. Back EMF observer(BEMF)

In recent years, Brushless Direct Current (BLDC) motor drives are increasingly popular in industrial applications due to fast progress of technologies in power electronics and the growing demand for energy saving. BLDC motors are a major part in automatic systems, as necessary to control the speed of BLDC motor for optimum performance. This paper proposes the design and modeling for sensorless speed control of BLDC motor using State Feedback Controller (SFC) with observer. In which the proposed method, derives full state feedback controller using pole placement technique and a trapezoidal back EMF is modeled as an unknown input. This observer has a high performance at low speed range, typically sensorless methods such as the scheme with back EMF detection method gives high performance at high speed range. Performance of the control technique is compared with conventional PI controller interms of settling time, tracking error, rise time and robustness with respect to disturbance. The purpose of this control technique is to keep the speed at desired reference speed. Control blocks are designed on MATLAB/Simulink using isolated functional blocks combine with the S-functions, and then model of BLDCM is established.