Fig. 1. Slip control-based induction motor sensorless scalar control system.
Fig. 2. Existing scalar speed feedback control algorithm.
Fig. 3. Vector control based slip estimator.
Fig. 4. Sensorless control of induction motor for treadmill system.
Fig. 5. Voltage controller for treadmill system.
Fig. 6. Rotor flux in the dr - pr reference frame.
Fig. 9. Simulation result of the proposed algorithm with 3Hz(90r/min) speed command.
Fig. 10. Simulation result of the proposed algorithm with 10Hz(300r/min) speed command.
Fig. 11. Experiment equipments.
Fig. 12. Experiment results of comparing speed control performance at 90r/min(0.6km/h) speed command. (a) conventional control algorithm. (b) proposed control algorithm.
Fig. 13. Experiment results of the proposed algorithm at 90r/min(0.6km/h) speed command (to show estimated speed & flux).
Fig. 14. Experiment results of the proposed algorithm at 300r/min(2km/h) speed command (to show estimated speed & slip, q-axis current).
Fig. 15. Experiment results of the proposed algorithm at 1300r/min(8.6km/h) speed command (to show estimated speed & flux).
Fig. 16. Experiment results of the proposed algorithm at 90r/min(0.6km/h) speed command with maximum brake torque (to show estimated speed & flux).
Fig. 7. The Closed-loop gopinath flux observer.
Fig. 8. Modified stator flux & slip observer.
TABLE 1 SIMULATION AND EXPERIMENT PARAMETERS
References
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