| The winding faults, such as rotor bar breaking, stator winding inter-turn short circuit and stator/rotor over-heating, are prevalent and potentially destructive in asynchronous motors. This paper focuses on the early detection of the winding faults in asynchronous motors, as would help avoid catastrophic failure, reduce repair cost and outage time to a great extent. Firstly, the fault features of rotor bar breaking and stator winding inter-turn short circuit are analyzed in this paper, deeply and thoroughly. Secondly, a series of novel detection schemes are presented creatively. Furthermore, this paper proposes the joint detection scheme for rotor bar breaking and stator winding inter-turn short circuit fault in squirrel cage asynchronous motors, for the first time. Meanwhile, a parameter identification technique based approach to detect stator/rotor over-heating fault is also presented. The validity and feasibility of the above-mentioned detection schemes has been verified by a great deal simulation and experiment results. Finally, the detection system for the winding faults in asynchronous motors has been developed successfully. The distinguished contributions of this paper are listed in details as the following.1. The multi-loop mathematical models under the conditions that the squirrel cage asynchronous motor is healthy, faulty with broken rotor bars or with stator winding inter-turn shorts are deduced thoroughly, and improved necessarily. And thus, the numerical simulation method, which is valid and practical, is formed. 2. For the first time, the transient simulation of rotor bar subsequent-breaking fault has been completed successfully. Also, the corresponding experiments have been carried out. Moreover, this paper systematically generalizes the rotor bar breaking fault features, and draws quite a few creative and interesting conclusions. Based on continuous subdivision Fourier transform, artificial neural network and self-adaptive filter technique, this paper presents a novel detection scheme for rotor bar breaking fault. Results of simulation and experiments demonstrate that the detection scheme is valid and feasible.The transient simulation of stator winding inter-turn short circuit fault has been completed successfully based on the multi-loop mathematical model. Also, the corresponding experiments have been carried out. According to that, this paper generalizes the stator winding inter-turn short circuit fault features systematically. By treating the average of stator negative sequence admittance as the fault feature, this paper proposes an artificial neural network based approach to detect stator winding inter-turn short circuit fault, whose sensitivity and reliability are satisfactory. At the same time, a continuous subdivision Fourier transform based approach to detect stator3. winding inter-turn short circuit fault, which selects the stator winding (equivalent) impedance angle as the fault feature, is presented. Furthermore, this paper points out that the lagging stator winding, adjacent to the faulty stator winding with inter-turn shorts, possesses the largest impedance angle among the three-phase stator windings, as allows to identify the faulty stator winding.4. The joint detection necessity for rotor bar breaking and stator winding inter-turn short circuit fault in squirrel cage asynchronous motors is clarified, and the corresponding joint detection strategy, valid and practical, is recommended for the first time, in this paper.5. A novel stator/rotor over-heating detection approach based on parameter identification technique is presented in this paper. Firstly, the stator/rotor resistances are identified on-line. Secondly, the corresponding temperatures are figured out according to the principle that the metal resistance linearly depends on its temperature. Finally, stator/rotor over-heating detection is accomplished.6. The detection system for the winding faults in asynchronous motors has been developed successfully, whose on-site application in Niang Ziguan power...
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