Improving Sensorless Control of BLDC Motors by Offering a New Parameters Estimation Algorithm for BLDC Motors

The existence of position sensors in the motor structure is one of the major problems of permanent magnet brush less dc (PM-BLDC) motors. In order to correct and optimized current commutation and also precise estimation of the motor speed meanwhile position sensors removal, various types of sensorless drives have been introduced which their algorithms estimate the rotor position. A group of these algorithms estimate the rotor position based on the calculating a function of the flux linkage. One of the major problems of this class of algorithms is the requirement to the exact values of motor parameters for correct operation, whereas motor parameters change as motor operation conditions change. Error in the motor parameters values can cause severe deterioration in the quality of rotor position and speed estimation and even lead to the motor instability. This paper proposes a new algorithm which is capable to estimate BLDC motors parameters quickly and accurately. Simulation results confirm good consistency between the parameters estimation algorithm and the sensorless algorithm. Copyright (C) 2011 Praise Worthy Prize S.r.l. - All rights reserved.