Study On Iron Core Loss Of The Induction Motor Considering Rotating Magnetic Property Of The Electrical Steel Sheets

The temperature field analysis and structure optimization design of modern electricalmachine put forward a higher request to the magnetic field calculations of electricalmachine. In this paper, we combine the modeling of rotating magnetic property ofelectrical steel sheets with the FEM, and the rotating iron loss is taking into considerationin this calculation. Based on the study on the two different kinds of rotating magneticproperty models, the programs of FEM calculation are achieved by FORTRAN, and thenthe magnetic field distribution is given. The results of iron loss calculated by differentmagnetic property models of electrical steel sheets are analyzed and compared with eachother. In addition, the calculation result is verified by a non-load experiment of a threephase induction motor in this paper.First of all, based on the given data of2-D magnetic properties, the study on therotating magnetic property model with high waves of magnetic field intensity is carried out,the formula and the equation set of the transient time-stepping finite element method whichis coupling with this magnetic property model are derived, and the program is achieved byFORTRAN, then the analysis on the transient time-stepping finite element method isrealized. At the same time, a delamination in the air gap between the stator and the rotor isallowed, the flexibly rotation of rotor with no surface re-mesh on rotor is realized and theskewness of element in the air gap between the stator and the rotor is avoided.Secondly, in this paper, we combine the complex rotating magnetic property modelwhich based on the effective magnetic parameters with harmonic finite element analysis,the flowchart of FEM calculation is given, then the harmonic finite element analysis ofinduction motor is realized by FORTRAN, and the magnetic field distribution in statorcore of induction motor is achieved.Then, based on the analysis above, the calculation methods of iron loss is introduced,the distribution of iron loss is achieved, and the result of iron loss distribution is comparedwith the one calculated by commercial software. Finally, we design a three-phase induction motor, and do an experiment of the motorunder the non-load running condition. The magnetic flux in the tooth and the yoke at theslots root is selected as comparison object to make the comparison between the measureddata and numerical simulation results by different magnetic property model, the calculatedmethods of magnetic field in induction motor by rotating magnetic property models areverified.