Rotor position identification method for multi-phase permanent magnet motor

Abstract

The invention discloses a rotor position identification method of a multi-phase permanent-magnet motor. The rotor position identification method comprises the following steps of (1-1) performing coordinate conversion of the multi-phase motor and decoupling of different harmonic planes; (1-2) extracting a position angle of d-axis magnetic flux of a non-fundamental wave plane rotor to obtain an angle Theta<r3> of three-harmonic rotor d-axis magnetic flux; (1-3) calculating a magnetic flux position angle Theta<r1> of a rotor fundamental wave plane of the motor; and (1-4) determining the position angle of the d-axis magnetic flux of the fundamental wave plane of the motor. The rotor position identification method has the characteristics that the dependence of rotor position identification on a motor parameter is casted off, the identification accuracy is improved, and better robustness is achieved.

Description

technical field [0001] The invention belongs to the technical field of multi-phase motors, and in particular relates to a rotor position identification method of a multi-phase permanent magnet motor with high identification accuracy without the dependence of rotor position identification on motor parameters. Background technique [0002] Polyphase motors (n>3 phases) have attracted attention due to their high reliability, multiple control degrees of freedom, and many other advantages, especially in applications such as ship propulsion, rail transit, and electric vehicles. The application of multi-phase permanent magnet motors has become increasingly widespread in recent years. [0003] Whether it is a three-phase permanent magnet motor or a multi-phase permanent magnet motor, the detection of the rotor position and speed is one of the keys to the implementation of the motor drive system. Usually, the rotor speed of the motor is obtained by measuring the optical encoder, ...

AI Technical Summary

Problems solved by technology

However, it needs to use parameters such as motor resistance and leakage inductance in the calculation process, which is highly dependent on the parameters of the motor. In practical applications, the motor parameters usually change with the working conditions and are not easy to obtain, which affects the accuracy of the algorithm.

Although the online identification of motor parameters can be combined to improve the accuracy to a certain extent, the high-precision online identification of motor parameters itself has great technical difficulties and is currently subject to certain restrictions, and the corresponding identification algorithm has a significant impact on the computing power of the controller and the cost of the chip. Higher requirements

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