| The five-phase induction motor has good fault-tolerant performance and can achieve low-voltage high-power output.As a multiphase motor with the least number of phases,it avoids the control problems caused by too many phases and is suitable for aerospace and ship propulsion.In this dissertation,the electromagnetic characteristics of five-phase induction motors with different winding types under normal and fault conditions are studied.It is determined that the star-pentagon winding has the best comprehensive performance among the five winding types.The temperature field of the five-phase induction motor connected by the star-pentagon winding under normal operation and fault operation is further calculated and analyzed.Firstly,the winding of five-phase induction motor is designed and analyzed.Based on the current three single winding structures of five-phase induction motor,which are star winding,pentagonal winding and pentacle winding,this dissertation designs star-pentagon winding and star-pentacle composite winding.The expression of magnetomotive force of single winding and composite winding is deduced.The harmonic distribution of air gap flux density under no-load of three single windings and two composite windings is analyzed by finite element method,and the correctness of the expression of magnetomotive force of single winding and composite winding is verified.Secondly,the starting characteristics,torque ripple,phase current,loss of the star winding,pentagonal winding,pentacle winding,star-pentagon winding and starpentacle winding under full load and overload are compared and analyzed.Through comparative analysis,it is concluded that the comprehensive performance of pentagonal star winding is the worst,and the comprehensive performance of starpentagon winding is the best.Since the multi-phase power inverter contains a large number of electronic devices,there may be power failure problems.In this paper,the phase current,torque ripple and loss of five-phase induction motor connected with five winding types under three fault conditions of one-phase power supply,adjacent twophase power supply and adjacent two-phase power supply are compared and analyzed.Combined with the electromagnetic performance of five windings under normal and fault conditions,the comprehensive performance of star-pentagon winding is determined to be the best.Finally,On the basis of the above research,based on the theory of fluid mechanics,the global temperature field of the five-phase induction motor with star-pentagon winding connection with the best comprehensive performance is simulated and analyzed.The temperature distribution law of each structural part of the five-phase induction motor with star-pentagon winding connection under normal operation and open-phase operation of power supply is studied,which provides a theoretical basis for subsequent motor fault monitoring and fault-tolerant control. |
