Sensorless control of the Switched Reluctance Motor drive at standstill and near-zero speed /
Due to its several inherent advantages, the Switched Reluctance Motor (SRM) drive is considered an attractive candidate for variable speed motor drive applications. Position information is essential for a high performance SRM drive. Mechanical position sensors are often used to provide rotor positi...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
2001.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=726104201&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Due to its several inherent advantages, the Switched Reluctance Motor (SRM) drive is considered an attractive candidate for variable speed motor drive applications. Position information is essential for a high performance SRM drive. Mechanical position sensors are often used to provide rotor position information for the SRM drive. However, these mechanical position sensors add to the cost and dimension and lower the reliability of the SRM drive. Several sensorless SRM control methods have been proposed. Most of these methods utilize the functional relationship between the stator flux linkage or phase inductance, phase current, and rotor position to estimate the rotor position. Depending on the way of phase flux linkage or inductance estimation, each of these published sensorless SRM control methods is suitable for a specific speed range. This dissertation proposes sensorless control methods for the SRM drive at standstill and near-zero speed. At near-zero speed, the incremental inductance of the active phase is estimated from the phase voltage equation by neglecting the back-emf term. An analytical phase incremental inductance model representing the relationship between the phase incremental inductance, phase current, and rotor position is developed by experiment and curve fitting. The phase incremental inductance estimated from the phase voltage equation is compared to a threshold obtained from the analytical phase increment inductance model to determine the commutation moment. In order to solve the ambiguity problem of the phase incremental inductance encoded position information, the incremental inductance of each phase is used for rotor position estimation only when it monotonically increases as the rotor moves from the unaligned position to the aligned position. In order to start the SRM without any hesitation, a new sensorless control algorithm for the SRM drive at standstill is also proposed in this dissertation. At standstill, each SRM phase is excited with a narrow voltage pulse. The resultant phase current amplitudes of all the phases are compared simultaneously to detect the phases capable of producing motoring torque at standstill. Simulation and experimental results are presented to verify the proposed sensorless control methods. |
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| Item Description: | Vita. "Major Subject: Electrical Engineering". |
| Physical Description: | xiii, 121 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 112-116). |