It is difficult to diagnose inter-turn short-circuit fault in dual three-phase high-speed permanent magnet motor in the early stage

which limits its application in aviation field. In allusion to the above problems

the circuit model of the dual three-phase high-speed permanent magnet motor under the condition of inter-turn short-circuit fault was established

and the analytical expression of the short-circuit current related to the motor's operating state and short-circuit parameters was deduced. A fault diagnosis method based on the model was proposed

by which the inter-turn short-circuit fault can be diagnosed accurately according to the imbalance of the stator current without additional sensors. The field-circuit coupled finite element simulation and prototype experiments of a 250 kW

23 000 r/min dual three-phase aviation high-speed permanent magnet starter-generator were carried out. The field-circuit coupled simulation and experimental results verify the accuracy of the proposed model

and indicate that the fault of the inter-turn short-circuit in early stage under the motor's dynamic loading and the wide-speed-range power generation conditions can be identified effectively and timely by the proposed fault diagnosis method

while also confirming the robustness of the proposed method

which provides a valuable reference for the inter-turn short-circuit fault diagnosis of aviation starter-generators.