| As an electromechanical integration speed motor, Switched Reluctance Motor (SRM) has been widely used in many fields, such as transportation, household appliances, general industrial, aviation and industrial servo system. It is known that proper positioning of phase excitation with respect to magnetic status of the machine is an integral part of a successful control in SRM drives. External position sensors have been traditionally used to serve this very purpose, however, the use of these sensros add to the cost and dimension and lead to reliability problems in harsh environments, then imposing limitations on the drive's application range. In this dissertation, a novel hybrid algorithm is developed respectively for low and high speed area application. Based on dSPACE real-time simulation system, a sensorless drive system for SRM is designed to confirm the feasibility and reliability of proposed algorithm.The paper first gives a general retrospect toward the development of SRM, and the fundamental operation principle of SR motor have been described. Afterwards, comprehensive review and analysis of the traditional indirect rotor-position estimation techniques for SR motor have been presented. Besides, a hybrid sensorless control strategy has been proposed. The hybrid sensorless scheme consists of a new current waveform detection technique for low speeds and standstill along with an improved current-flux algorithm for high speed area. As for the novel current waveform detection approach, it also utilizes the geometrical characteristic of inductance curves in three-phase switched reluctance motors, with special signal processing circuit to comparing inductance eigenvalue. The improved flux-linkage algorithm adopted in high speed application makes full use of the structural symmetry of SRM, and magnetic characteristics only for some specific position are required. Based on the Fourier series and curves-fitting strategy, a simplified flux-linkage analytical model with a good degree of accuracy has been proposed. In addition, Based on MATLAB/Simulink software, the simulation model of position sensorless control system of SR motor has been built. The detail simulation results verify the feasibility of proposed method for the whole speed area application.Finally, the proposed algorithm are implemented using the rapid control prototyping hardware'dSAPCE'based on a 10/8 SRM prototype. The hardware circuits including the inner configuration of dSPACE platform and software design of position sensorless system have been described. Meanwhile, the ControlDesk environment of dSPACE real-time simulation system and the characteristics of this system are enumerated as well. A series of experimental research are conducted based on the hardware platform to validate proposed indirect rotor position sensing method. The preliminary experimental results analysis shows the feasibility of proposed strategy, which lays the theoretical and practical foundation for the position sensorless control of SR motor in some degree.
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