Speed -Sensorless Vector Control of Parallel Connected Induction Motor Drive Fed by a Single Inverter using Natural Observer

This paper describes the speed sensorless vector control method of the parallel connected induction motor drive fed by a single inverter. Speed and rotor fluxes of the induction motor are estimated by natural observer with load torque adaptation and adaptive rotor flux observer. The performance parameters speed and rotor fluxes are estimated from the measured terminal voltages and currents. Fourth order induction motor model is used and speed is considered as a parameter. The performance of the natural observer is similar to the conventional observer. The speed of an induction motor is estimated by MATLAB simulation under different speed and load conditions. Estimated values along with other measured states are used for closed loop control. The simulation results show that the natural observer is also effective for parallel connected induction motor drive.

• R. Gunabalan
• V. Subbiah

• natural observer
• adaptive observer
• sensorless control

[1] B.K.Bose, "Modern Power Electronics and AC Drives",Upper Saddle
River, NJ: Prentice-Hall, 2001, pp.348-350.
[2] H. Kubota and K. Matsuse, "Speed sensorless field-oriented control of
induction motor with rotor resistance adaptation," IEEE Trans.
Industrial Applications, vol. 30, pp. 1219-1224, Sept. /Oct. 1994.
[3] H. Kubota, K. Matsuse, and T. Nakano, "DSP-Based Speed Adaptive
Flux Observer of Induction Motor," IEEE Trans. Industrial
Applications, vol. 29, pp. 344-348, Mar./Apr. 1993.
[4] K.Matsuse, Y.Kouno, H.Kawai and J.Oikawa, "Characteristics of speed
sensor-less vector controlled dual induction motor drive connected in
parallel fed by a single Inverter", IEEE Trans .Industrial Applications.,
vol. 40, pp. 153-161, Jan./Feb. 2004.
[5] K. Matsuse, Y. Kouno, H. Kawai and S. Yokomizo, "A Speed-sensorless
vector control method of parallel-connected dual induction motor
fed by a single inverter," IEEE Trans. Industrial Applications, vol. 38,
pp. 1566-1571, Nov./Dec. 2002.
[6] Sidney R. Bowes, Ata Sevinc and Derrick Holliday, "New natural
observer applied to speed sensorless DC servo and induction motors,",
IEEE Trans. Industrial Applications., vol. 51, no.5, pp. 1025-1032, Oct.
2004.