Contact resistance estimation method for turn-to-turn short circuit fault of six-phase permanent magnet synchronous motor

The invention discloses a contact resistance estimation method for a turn-to-turn short-circuit fault of a six-phase permanent magnet synchronous motor, and the method comprises the steps: employing a state observer which employs an x-y current and a short-circuit current as state variables, and enabling a search function containing an x-y subspace current to be used for the online estimation of the contact resistance, compared with a traditional method, the method has the advantages that the signal-to-noise ratio of fault features is increased, a new possibility is provided for online estimation of turn-to-turn short circuit fault parameters of the six-phase permanent magnet synchronous motor, and the method has a good application prospect in the fields of aerospace, electric automobiles and high reliability. In addition, the method is high in flexibility, and the search range of the contact resistance can be customized according to the wire diameters and sensitivity requirements of different motor windings.