TY - JOUR

T1 - Energy-Preserving Methods and Torque Computation from Energy Balance in Electrical Machine Simulations

AU - Perkkiö, Lauri

AU - Rasilo, Paavo

AU - Silwal, Bishal

AU - Hannukainen, Antti

AU - Arkkio, Antero

AU - Eirola, Timo

PY - 2016/8/1

Y1 - 2016/8/1

N2 - The finite-element analysis for the simulation of magnetic fields in electrical machines leads to an index-1 differential-algebraic equation (DAE) (as opposed to a conventional ordinary differential equation), because the electrical conductivity can be zero in certain regions. First, we construct a DAE-compatible time integration scheme which is energy-balanced, meaning that in a linear system, the input stored and lost powers sum exactly to zero. Second, we use a method based on the energy balance to compute torque. We show that the energy balance method approaches the virtual work principle applied at remeshing layer, as the time step is refined. A similar result also holds if the rotation of the rotor is implemented by Nitsche's method, which is an instance of the so-called mortar methods.

AB - The finite-element analysis for the simulation of magnetic fields in electrical machines leads to an index-1 differential-algebraic equation (DAE) (as opposed to a conventional ordinary differential equation), because the electrical conductivity can be zero in certain regions. First, we construct a DAE-compatible time integration scheme which is energy-balanced, meaning that in a linear system, the input stored and lost powers sum exactly to zero. Second, we use a method based on the energy balance to compute torque. We show that the energy balance method approaches the virtual work principle applied at remeshing layer, as the time step is refined. A similar result also holds if the rotation of the rotor is implemented by Nitsche's method, which is an instance of the so-called mortar methods.

KW - Electric machine

KW - energy balance

KW - non-matching mesh

KW - torque

UR - http://www.scopus.com/inward/record.url?scp=84979678850&partnerID=8YFLogxK

U2 - 10.1109/TMAG.2016.2537263

DO - 10.1109/TMAG.2016.2537263

M3 - Article

AN - SCOPUS:84979678850

VL - 52

JO - IEEE Transactions on Magnetics

JF - IEEE Transactions on Magnetics

SN - 0018-9464

IS - 8

M1 - 7209708

ER -