Sensorless control method for five-phase permanent magnet fault-tolerant motor

Abstract

The invention discloses a sensorless control method for a five-phase permanent magnet fault-tolerant motor, and belongs to the technical field of sensorless control of multi-phase motors. The method comprises the following steps: firstly, establishing a mathematical model of any two phases of the five-phase permanent magnet fault-tolerant motor based on counter electromotive force; constructing a current state observer based on any two-phase signal by utilizing a hyperbolic function so as to obtain a corresponding opposite potential; and then constructing a general phase-locked loop module, inputting the normal two-phase counter electromotive force into the general phase-locked loop module, and calculating to obtain the rotating speed of the motor and the position of the rotor. The method can effectively suppress high-frequency buffeting in the system, solve the problem of phase delay, and improve the estimation precision of the rotor position; coordinate transformation is omitted, and the robustness of the system is improved, so that the motor has relatively good tracking capability under a fault mode and parameter change disturbance; and in addition, the algorithm is small in calculation amount, simple and easy to implement, and engineering and practicability of a new theory are facilitated.

Description

technical field [0001] The invention belongs to the technical field of position sensorless control of multiphase motors, in particular to a position sensorless control method for five-phase permanent magnet fault-tolerant motors. Background technique [0002] Five-phase permanent magnet fault-tolerant motor has the advantages of high efficiency, high power density, wide speed range, low torque ripple and strong fault tolerance, and has been widely concerned and applied in aerospace, electric vehicles, ship propulsion systems and other fields. For the five-phase permanent magnet fault-tolerant motor control system, a mechanical position sensor is generally required to detect the rotor position and speed. However, the use of mechanical sensors will not only increase the cost and volume of the system, but also reduce the reliability of the system, thereby limiting the application in high-performance drive applications. Therefore, the research on position sensorless control of ...

AI Technical Summary

Problems solved by technology

However, the phase windings of the motor in the fault mode are in an asymmetric operation state, and the normal phase current will be distorted. If the observer is directly constructed by coordinate transformation, the estimation accuracy in the fault mode will be greatly reduced

In addition, the problems of traditional sliding mode observers will be further exacerbated in the failure mode

Images