Non-adjacent two phase open-circuit fault-tolerant vector control method for five-phase permanent magnet embedded fault-tolerant linear motor

Abstract

The invention discloses a non-adjacent two phase open-circuit fault-tolerant vector control method for a five-phase permanent magnet embedded fault-tolerant linear motor. The method disclosed by the invention comprises the steps of solving fault-tolerant current of healthy phases by taking that two adjacent phases are equal in current amplitude as a constraint condition according to principles that traveling waves are constant in magnetomotive force before and after a fault and the sum of healthy-phase current is zero, and thus deducing a popularization Clarke transformation matrix of transformation of a natural coordinate system where the healthy phases are located to a two-phase static coordinate system; estimating the healthy-phase counter potential by adopting the transpose of the transformation matrix; and transforming a nonlinear strong-coupling system of the type of motor at a non-adjacent two phase open-circuit fault state into a one-order inertia system by adopting a current internal model controller, a one-order inertia feedforward voltage compensator and a counter potential observer. The method disclosed by the invention suppresses thrust ripples caused by a motor fault. More importantly, the dynamic performance and the steady-state performance are consistent with the performance at a normal state, overshoot-free quick response is realized, and the switching frequency of a voltage source inverter is constant.

Description

technical field [0001] The invention relates to a fault-tolerant control method for non-adjacent two-phase open-circuit faults of permanent magnet linear motors, in particular to a fault-tolerant vector control method for non-adjacent two-phase open-circuit faults of five-phase fault-tolerant permanent magnet linear motors. It is suitable for occasions that have high requirements on the reliability and dynamic performance of the motor, such as aerospace, electric vehicles, deep sea, and medical equipment. Background technique [0002] With the development of society and the improvement of people's living standards, the requirements for the comfort, safety and stability of car driving are getting higher and higher. As an important part of modern automobiles, the performance of the suspension system has an extremely important impact on the ride comfort and operational stability of the vehicle. Therefore, the research on active suspension systems has been highly valued by the i...

AI Technical Summary

Problems solved by technology

[0004] In view of the deficiencies in the existing motor fault-tolerant control technology, as well as the characteristics of the five-phase permanent magnet embedded fault-tolerant linear motor proposed by the present invention and the non-adjacent two-phase open-circuit fault characteristics of this type of motor, the purpose of the present invention is to overcome the non-phase fault of the motor. The existing fault-tolerant strategy uses current hysteresis control after adjacent two-phase open-circuit faults, resulting in disordered switching frequency of the inverter, reduced motor response speed, poor dynamic performance, inability to accurately follow the current, and severe noise. The existing fault-tolerant vector control strategy cannot be realized. Due to the defect of fault-tolerant operation under the condition of two-phase open-circuit fault, and the problem of difficult parameter adjustment caused by the contradiction between the rapid response and overshoot of traditional current PI control, a five-phase permanent magnet embedded fault-tolerant straight line used in the present invention is proposed The non-adjacent two-phase open-circuit fault-tolerant vector control method of the motor realizes the accurate estimation of the back EMF, reduces the difficulty of controller parameter adjustment, and realizes the high fault-tolerant performance and high dynamic performance of this type of motor system under the condition of adjacent two-phase open-circuit faults 1. The current has good followability, reduces CPU overhead, realizes constant switching frequency of the inverter, reduces noise, facilitates electromagnetic compatibility design, and then improves the non-adjacent two-phase open-circuit fault state of the five-phase permanent magnet embedded type fault-tolerant linear motor of the present invention Dynamic performance and reliability under

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