Noriaki Fukushima

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In this paper, we propose and validate a method for the accurate estimation of iron loss in rotating machines. In this method, the eddy current loss in electrical steel sheets is directly calculated by nonlinear time-domain electromagnetic field analysis with a simple approximation of the excess loss. The hysteresis loss is also estimated by considering the(More)
Two calculation methods for iron-loss estimation of rotating machines are investigated. One is based on the conventional three-term expression. In this case, the losses are calculated from the time variation in the flux density obtained by the finite element analysis, which approximates the stator and rotor cores as solid magnetic materials without(More)
A post 1-D analysis of laminated cores is developed for estimating the torque and loss in rotating machines. The 1-D nonlinear eddy-current analysis along the thickness of electrical steel sheets is carried out at each element in the main finite-element analysis in order to estimate the loss and the harmonic torques caused by the eddy currents and the(More)
In this study, we propose and confirm an accurate estimation method of iron loss in rotating machines. In the method, the eddy-current loss in the electrical steel sheets is directly calculated by a nonlinear time-domain electromagnetic field analysis with a simple approximation of the excess loss. The hysteresis loss is also estimated with the(More)
We have obtained new inelastic neutron scattering (INS) data for the molecular magnet Mn12-acetate which exhibit at least six magnetic peaks in the energy range 5–35meV. These are compared with a microscopic Heisenberg model for the 12 quantum spins localised on the Mn ions, coupled by four inequivalent magnetic exchange constants. A fit to the magnetic(More)
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