Method for estimating rotor position of switched reluctance motor without position sensor

Abstract

The invention discloses a method for estimating the rotor position of a switched reluctance motor without a position sensor, and belongs to the technical field of the control of the switched reluctance motors. In the method, based on the fundamental feature that an inductor of the switched reluctance motor is changed periodically with the rotor position, phase inductance reaches maximum at a position where a stator is aligned with a rotor, so the slope of the phase inductance is changed into negative from positive at the maximum position of the inductance, and slope zero-crossing points exist. In the method, by sampling each phase current and phase voltage in real time, each phase inductance value can be detected in real time, and simultaneously, the inductance slope can be calculated; the calculated inductance slope is subjected to zero balancing to obtain pulse signals of the slope zero-crossing points, so that a zero-crossing position, namely the position where a stator tooth pole is aligned with a rotor tooth pole can be detected; and the phase difference of the two adjacent maximum inductance positions is 45 degrees, so the difference of positions of the two slope zero-crossing points is 1/8 cycle, and the real-time rotate speed and rotor position information of the motor can be calculated according to the zero-crossing pulse signals. The method has the advantages of independent of parameters of a motor body, no need of measurement of motor characteristics such as static flux linkage and the like, simple algorithm and easy realization, so the method has strong generality compared with a non-position strategy.

Description

technical field [0001] The invention relates to a position sensorless rotor position estimation method of a switched reluctance motor, which belongs to the technical field of switched reluctance motor control. Background technique [0002] Switched Reluctance Motor (SRM), as a new type of speed control system, not only has the basic advantages of AC and DC speed control, but also has unique high-speed performance and fault tolerance. This makes it widely concerned in the field of AC and DC drives in aerospace and various civil manufacturing industries, and undoubtedly has a good application prospect and market value. For switched reluctance motor systems, real-time and accurate rotor position information is a prerequisite for reliable operation and high-performance control. In current practical applications, shaft position sensors or other detecting position detectors are generally used to obtain position information, which not only increases the cost and complexity of the ...

AI Technical Summary

Problems solved by technology

[0005] To overcome the problems of the traditional relative positionless algorithm based on flux linkage or inductance, the preparation work is complex, the algorithm has many error sources, and the portability is poor, and a simple, easy-to-implement, and versatile position sensorless position estimation strategy is obtained

Images