Sensorless control algorithm of BLDC motors with current model

This paper proposes a new sensorless control algorithm of BLDC(Brushless DC) motors with current model based on the 120 degree conduction mode. The rotor speed and the position can be estimated by using the current model of BLDC motor which is modified version of the conventional current model of PMSM(Permanent Magnet Synchronous Motor) sensorless method. The rotor position and the speed can be obtained by using the difference of the actual current and the model current. The position error caused by the parameter errors of the current model, current distortion at commutation points and nonideal trapezoidal shape of back-EMF is also compensated by using simple PI controller and the feedback loop of the real current. The validity of the proposed sensorless control algorithm is verified through several experiments.

[1]  R. Wu,et al.  A permanent magnet motor drive without a shaft sensor , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[2]  Jang-Mok Kim,et al.  Sensorless Control of Brushless DC Motors With Torque Constant Estimation for Home Appliances , 2012, IEEE Transactions on Industry Applications.

[3]  Chung-Wen Hung,et al.  Position Sensorless Control for Four-Switch Three-Phase Brushless DC Motor Drives , 2008, IEEE Transactions on Power Electronics.

[4]  J. C. Moreira,et al.  Indirect sensing for rotor flux position of permanent magnet AC motors operating over a wide speed range , 1994 .

[5]  Nobuyuki Matsui,et al.  Sensorless PM brushless DC motor drives , 1996, IEEE Trans. Ind. Electron..

[6]  Kenichi Iizuka,et al.  Microcomputer Control for Sensorless Brushless Motor , 1985, IEEE Transactions on Industry Applications.

[7]  H. Akagi,et al.  An approach to position sensorless drive for brushless DC motors , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[8]  Z.Q. Zhu,et al.  Sensorless flux-weakening control of permanent-magnet brushless machines using third harmonic back EMF , 2004, IEEE Transactions on Industry Applications.

[9]  J. Moreira Indirect sensing for rotor flux position of permanent magnet AC motors operating in a wide speed range , 1994, Proceedings of 1994 IEEE Industry Applications Society Annual Meeting.

[10]  Nesimi Ertugrul,et al.  A new algorithm for sensorless operation of permanent magnet motors , 1992, Conference Record of the 1992 IEEE Industry Applications Society Annual Meeting.