Study On Switched Reluctance Motor Drives Without Rotor Position Sensor

Switched Reluctance Mortor, SRM for short, is also named Variable Reluctace Motor. It is different from other tridicitonal motors on structure, its stator and rotor are all salient pole type and there are winds in its stator only. Stator and rotor are also pressed to a whole with silicon-steel sheets. The structure of SRM is sample and the costs are low, SRM is also efficient. Because of more control parameters, simple, high reliability and good control performance, Switched Reluctance Motor Drives, SRD for short, have being payed more and more attention. However, knowing rotor position in real time is a prediction of SRD to work well. Within sensor traditionally, the firmness, stability and reliability are adverse affected. So, it is very necessary to research on sensorless SRD, and it is a Hotpoint now.Sensorless SRD was studied in this paper, and simulations are made and analyzied. The main achievements are as follows:Mathematical models of SRM were constractive analysied, and based on this, simulation models were built up and models were simulated and analysed. Based on these simulation models, operation and control models were simulated and anslysied relatively.A thorough study on the technology of rotor position detection of SRM was made in detail. A new method was proposed in the paper. In this method, a short detecting voltage was applied on the phase winds, detecting current generated by the short voltage was detected and processed, according to the relationship between the current waveform and rotor position, the position that the front edge of rotor aligns to the back edge of stator will be identified. Then based on structural parameters of SRM, the position of rotor is derived indirectly without position sensor. The relative simulation model was built up, and the proposed method was simulated, and the results prove the validity of the new method.The starting of SRM was investigated partly in this thesis. An advanced way to detect initial rotor position and starting-phase was raised. Acording to the result searched table with the inductance surveyed before starting and the ordinal relation of the other 2-phases inductance, rotor position and starting-phase can be obtained. Thoey of the new method was introduced in the thesis According the proposed sensorless method, the simulation model of sensorless SRD was built up within the starting method of one phase excited. Relative simulation was made, and the results indicate SRD works well.