ABSTRACT:
A novel speed sensorless direct torque control system-SVM-DTC of permanent magnet synchronous motor (PMSM) based on SVM and MRAS is presented. In this paper the various components of the speed sensorless SVM-DTC and the principle of realization are discussed in detail. Finally the simulation results with the application of MATLAB/SIMULINK show that the speed identification algorithm is accurate and of robustness, moreover, the whole control system has good static and dynamic performances.
KEYWORDS:
1. Permanent magnet synchronous motor (PMSM)
2. Space Vector Modulation (SVM)
3. Direct torque control (DTC)
4. Model reference adaptive system (MRAS)
SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Fig.1. Speed-sensor less SVM-DTC diagram.
EXPECTED SIMULATION RESULTS:

Fig.2 (a) Estimated speed curve Fig.2 (b) Actual speed curve

Fig.2 (c) Speed error curve Fig.2 (d) Torque response

Fig.2(e) A-phase stator current waveform Fig.3 (a) Estimated speed curve

Fig.3 (b) Actual speed curve Fig.3 (c) Speed error curve

Fig.3 (d) Torque response Fig.3 (e) A-phase stator current waveform
CONCLUSION:
In this paper, the speed sensorless SVM-DTC system based on SVM and MRAS is presented and the control system has a clear control principle and structure. Simulation results show that the speed identification algorithm can estimate accurately the real speed and has robustness to varying of stator resistor. Moreover the speed sensorless SVM-DTC system has good static and dynamic performance.

REFERENCES:
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