Phase Band Scheme Magnetomotive Force Harmonic Analysis And Winding Arrangement And Optimization Of Five Phase Asynchronous Motor

The multiphase motor has the advantages of low voltage and high power drive,which greatly improves the operation reliability in electric vehicles and aerospace and other fields.As a polyphase motor with relatively few phases,five-phase asynchronous motor can reduce the cost and is easy to control.In five-phase asynchronous motor,windings are the key to realize electromechanical energy conversion.In this paper,the phase band scheme of the five-phase winding is analyzed by magnetomotive force harmonic,according to the fundamental wave distribution coefficient and harmonic content,the winding of a 15 k W five-phase asynchronous motor is arranged.Then,the prototype is designed and analyzed to optimize the low harmonic winding.Firstly,the phase band scheme of five-phase winding is analyzed by magnetomotive force harmonic.Using the groove number phase diagram method,harmonic analysis is carried out for the phase band scheme with the denominators D of each phase groove number of each pole being odd and even respectively,including deducing the 36 degree phase band winding.Distribution coefficient and harmonic content of 72 degree phase band winding and small phase band winding.Secondly,the prototype is arranged with windings.According to the above derivation,based on the harmonic content of the five-phase synthetic magnetomotive force,the reason why the prototype selected the integer slot winding group was explained,and the phase-band scheme which could make the prototype have a larger fundamental wave distribution coefficient and less harmonic content of the five-phase synthetic magnetomotive force was found for slot number allocation.Then,based on the amplitudes of the positive and negative sequence components of the five-phase synthetic fundamental wave magnetomotive force,the rationality of slot number allocation was proved,and the prototype was analyzed by finite element simulation to check the rationality of the simulation results such as the distribution of magnetic field lines.Finally,the prototype is designed and analyzed to optimize the low harmonic winding.Starting from the principle of low harmonic winding,the harmonic analysis is carried out,and the turns ratio suitable for the prototype is selected to weaken the harmonic of magnetomotive force.Then,the average half-turn length of the coil is calculated and compared with the original winding and the pitch leakage resistance coefficient is calculated.Next,the two windings are compared through simulation to check the optimization effect.