Multiscale Computations of Parameters of Power Transformer Windings at High Frequencies. Part II: Large-Scale Level

In this part of the paper, we focus on implementation of a hierarchical multiscale approach for modeling high-frequency electromagnetic processes in power transformers. We present a large-scale 3D computer model for calculating magnetic fields in a transformer and evaluating effective parameters (inductance and resistance) of its windings and losses. The model accounts for complex, anisotropic, and frequency-dependent effective diamagnetic properties of the windings, which are obtained by solving small-scale 2D field problems as described in Part I of the paper. Results of the computations performed for a test transformer are analyzed in the frequency range 10 Hz-10 MHz. We discuss effects of windings conditions (open and short-circuited) and their location on the transformer core.

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