A method for srm position estimation based on linear flux linkage model and linear regression analysis

Abstract

The invention discloses an SRM position estimation method based on a linear flux model and linear regression analysis. According to the method, only the flux characteristic data of any two rotor positions in a linear region are required so that the flux values of the two endpoints of the linear region are obtained and act as the reference. The conduction phase voltage and current values are detected, and the flux value is calculated. If the value is between the two reference flux values, the rotor positions are located in the linear region, and position estimation is performed by applying the linear flux model, or the rotor positions are located in the non-linear region, linear regression analysis is performed on the linear region position data and the sampling sequence number under the premise of supposing that the rotating speed of the motor is constant in a short period of time, and then estimation of the rotor positions in the nonlinear region is performed. The multiphase flux characteristics can be adopted to replace the single-phase flux characteristics to perform position estimation if the accumulative error in single-phase estimation requires to be further reduced. The method is high in accuracy, easy to implement and great in applicability and can avoid or reduce the influence of inter-phase mutual induction and saturation of the magnetic circuit.

Description

technical field [0001] The invention relates to an accurate position estimation method of a switched reluctance motor (SRM) based on a linear flux model and linear regression analysis, and belongs to the field of motor position sensorless control. Background technique [0002] Position information is fundamental to the operation of switched reluctance motors. Usually, position information is obtained by mechanical position sensors, such as resolvers, Hall sensors, photoelectric encoders, etc. However, these mechanical position sensors not only increase the cost and complexity of the drive system, but also their accuracy and reliability are easily affected by environmental factors such as temperature, dust and vibration. Therefore, it is very necessary to study a position sensorless control method with low cost, high precision and high reliability. [0003] In order to realize position sensorless control, researchers have proposed a large number of position estimation metho...

AI Technical Summary

Problems solved by technology

The disadvantages of this type of method are: when there is current in other phases, the pulse current injected into the phase may be affected by other interactions; the pulse current injected into the non-conductive phase may generate negative torque; in addition, at high speed, the excitation current waveform occupies The main part of the entire phase period, limiting the time of pulse injection

However, most of the existing conduction phase position estimation methods require the flux linkage characteristic data at all or many rotor positions, which increases the difficulty and workload of data acquisition and processing, and often requires a large storage space

In addition, the prediction accuracy of this type of method is easily affected by the mutual inductance of the phases and the saturation of the magnetic field

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