A Stator Flux Estimation Method Based on Duty Cycles of Inverter Switching

This paper presents a stator flux estimation method based on duty cycles of inverter switching. The stator flux is calculated by integrating the back electromotive force, which is the terminal voltage minus the voltage drop on the stator resistance. The terminal voltage mentioned above is calculated by the duty cycles of inverter switching and dc link voltage, while the duty cycles is derived in the digital control system of induction motor based on the DSP. Without employing voltage sensors to measure phase voltage, the proposed flux estimation method is cost effective and error reducing. The method is also effective in fault-tolerant operation when the motor works with two phases. Experimental results verify the effectiveness of the proposed method.

[1]  Matthew W. Dunnigan,et al.  Phase voltage estimation of a PWM VSI and its application to vector-controlled induction machine parameter estimation , 2000, IEEE Trans. Ind. Electron..

[2]  Silverio Bolognani,et al.  Experimental fault-tolerant control of a PMSM drive , 2000, IEEE Trans. Ind. Electron..

[3]  Juha J. Pyrhönen,et al.  Estimation of the flux linkage in a direct-torque-controlled drive , 2003, IEEE Trans. Ind. Electron..

[4]  M. Pucci,et al.  A new adaptive integration methodology for estimating flux in induction machine drives , 2004, IEEE Transactions on Power Electronics.

[5]  D. Howe,et al.  Direct torque control of three-phase PM brushless AC motor with one phase open-circuit fault , 2009, 2009 IEEE International Electric Machines and Drives Conference.

[6]  H. Tajima,et al.  Speed sensorless field orientation control of the induction machine , 1991, Conference Record of the 1991 IEEE Industry Applications Society Annual Meeting.

[7]  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.

[8]  C. Cossar,et al.  A General Magnetic-Energy-Based Torque Estimator: Validation via a Permanent-Magnet Motor Drive , 2008, IEEE Transactions on Industry Applications.