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[TechVid]

There's a model of motor with 6 poles, shaft & rotor. The model got meshed in APDL, defined material for air volume, B-H curves for shaft and rotor and copper for coil. Now these coils are modeled in slot shape with two semi-circular sides, so it's stranded coil. It's difficult to define the current,number of turns and current direction.

I have a batch file, it takes forever to converge, I sense a big error behind the physics not getting converged.

[Karthik Remella]

Hello,nI moved this post to the Structures category for better alignment. I hope this helps.nThank you.nKarthikn

[Ashish Khemka]

nnPlease refer to following link in Ansys Help that might be useful -nRegards,nAshish Khemkan

[Ashish Khemka]

nnI am moving this post to Electronics as this looks more relevant to Ansys Maxwell.nnRegards,nAshish Khemkann

[wrbulat]

As this is a MAPDL model, presumably the element types you are using are SOLID236/237.nSometimes the analysis objective is to simulate a locked (non-rotating) rotor condition with DC coil energization. Far more complicated is the simulation of an operating motor (rotor spinning) with voltage-fed coils, with analysis objectives of calculating resulting coil current (considering induced back-emf due to rotor speed), delivered torque, efficiency, and torque ripple. nFor both cases you want separate element coordinate systems (ESYS attribute) assigned to different regions of each coil. The semicircular ends should have cylindrical coordinate systems assigned to them (circumferential or y direction direction aligned with coil strands). The centers of the cylindrical coordinate systems should coincide and be aligned with the centers of the semicircular ends. For convenience, for the straight legs of the coils, it is best to create ESYS Cartesian coordinate systems that also have their y directions aligned with coil strands and in the same direction that coil current flows.nFor the former case, you can define coil solenation in terms of current density (e.g., A/m^2) using the BFE command, Lab=JS, nIn the latter case the coils should use the stranded conductor option (keyopt(1)=2). There are real constants that are required for this option (image below):nnIs your BH data entered in units of B=Tesla, H=A/m, or have you entered the data in units of B=Gauss, H=Oersted? I almost always convert the latter to the formed and use MKS units for all aspects of modeling and solving (I find it easier).nnnIt's remotely possible that (if you are doing a DC locked rotor analysis) you are using the legacy MSP element type SOLID96. Is this the case?nBest,nBilln

[TechVid]

Hello Bill,nAs I can see you definitely understood the whole model. Yes I'm going with SOLID 237. As you can see, according to the shape of coil it's required to define multiple cylindrical co-ordinate systems with origin at the center point of circular turns. It's bit of too much work tho, defining ESYS at perfect co-ordinate point.nAnd Yes, I'm going with defining real_constants for stranded coil rather using SOURCE36 to model FE model of coil.nWhich one of these two methods would you recommend to define Stranded coil?nAnd about material properties,yes , I have verified it with standard input file and made sure that I'm not missing any data.nAlso, I'm not being able to define the current density in the coil as there's no 2d surface, while current density must be defined. Shall i rely on real_constants?.n