A method for efficiently deriving a reduced-order model of a cage induction motor (IM) with skewed rotor slots is proposed based on the multiport Cauer ladder network (CLN) method. This paper presents several formulations of the multiport CLN method for the skewed rotor, in which the continuity of the bar currents and the space harmonics included in the air-gap flux density waveform are treated differently. The effectiveness of the developed methods was verified from the viewpoints of computational accuracy and cost through application to a practical cage IM with skewed rotor slots.

No abstract

An anisotropic vector play model was developed by the superposition of scalar play models. An analytical identification method was derived for a uniaxially anisotropic term. Computed BH loops accurately reconstructed the measured anisotropic hysteretic characteristics of non-oriented silicon steel sheet. Its application to magnetization analysis by a physical magnetization model using multi-domain particles enhanced the prediction accuracy of the stress-dependent loss property.

No abstract

This paper proposes a new convergence acceleration method specialized for the magnetic field analyses of synchronous machines based on the time-periodic explicit-error-correction (TP-EEC) method. The proposed method constructs an auxiliary equation for error correction in the dq rotational reference frame to convert a fundamental harmonic component into a DC component. This conversion enables us to perform error correction using the TP-EEC method at intervals of an arbitrary number of time steps. The effective time intervals for error correction were investigated using practical interior permanent magnet synchronous motor (IPMSM) models. Moreover, DC superimposed problems, such as PMSMs with an open-end winding, were examined. Numerical results verified the effectiveness of the proposed method, and smaller time intervals could significantly improve the convergence characteristics of the transient analysis when high-order harmonic components were small. Furthermore, by adopting a 1/6 period as the time interval for the proposed method, a steady-state solution could be obtained precisely, even in a time-periodic problem that included many high-order harmonic components.