Fault-tolerant field-oriented control method for non-adjacent two-phase short circuits of five-phase permanent magnet-embedded fault-tolerant linear motor

Abstract

The invention discloses a fault-tolerant field-oriented control method for non-adjacent two-phase short circuits of a five-phase permanent magnet-embedded fault-tolerant linear motor. Non-fault-phase fault-tolerant current is calculated according to the principles that pre- and post-fault traveling wave magnetomotive force is constant and the sum of non-fault-phase current is zero; a nonlinear strong coupling system of the motor in a fault state is converted into a first-order inertia system by employing an internal model controller, a first-order inertia feedforward voltage compensator and a counter electromotive force observer; non-fault-phase voltage commands are calculated on this basis and the voltage commands and counter electromotive force of various phases are added respectively to achieve fault-tolerant field-oriented control on the non-adjacent two-phase short circuits of the motor. Motor output thrust fluctuation caused by the non-adjacent two-phase short circuits of the motor is inhibited; fault-tolerant operation that one of the non-adjacent two phases is in an open-circuit fault and the other one is in a short-circuit fault can be achieved; more importantly, the dynamic property and the steady-state performance of the motor are consistent with those in a normal state; and a voltage source inverter is constant in switching frequency and has certain universality.

Description

technical field [0001] The invention relates to a fault-tolerant control method for non-adjacent two-phase short-circuit faults of five-phase permanent magnet motors, in particular to a fault-tolerant magnetic field oriented control method for non-adjacent two-phase short-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...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the deficiencies in the existing motor fault-tolerant control technology, according to the characteristics of the five-phase permanent magnet embedded fault-tolerant linear motor and the non-adjacent two-phase short-circuit fault characteristics of this type of motor, the purpose of the invention is to overcome the non-adjacent two-phase short-circuit of the motor The current fault-tolerant strategy uses current hysteresis control after a fault, resulting in disordered switching frequency of the inverter, reduced motor response speed, poor dynamic performance, inability to follow the current accurately, and severe noise. Traditional current PI control has the disadvantages of rapid response and overshoot. Contradictions lead to the problem of difficult parameter adjustment, and the existing fault-tolerant vector control strategy cannot realize the fault-tolerant operation of the two-phase short-circuit fault situation. A non-adjacent two-phase permanent magnet embedded fault-tolerant linear motor for the present invention is proposed. The short-circuit fault-tolerant rotor field-oriented control method realizes the accurate estimation of the back EMF, reduces the difficulty of controller parameter adjustment, and realizes high fault-tolerant performance, high dynamic performance, and good current follow-up of this type of motor system in the state of non-adjacent two-phase short-circuit faults performance, reduce CPU overhead, realize constant inverter switching frequency, reduce noise, and then improve the dynamic performance and reliability of the five-phase permanent magnet embedded fault-tolerant linear motor of the present invention under the non-adjacent two-phase short-circuit fault state

Images