Study of Nonlinear Characteristic Curve for the Core of Transformer with Magnetic Coupling

Nonlinear characteristics for the core of transformer is very important in computing exciting current or etc.a few of articles utilize improperly the nonlinear characteristic.For example,φ-i curve is regarded to be conformable to B-H curve regardless whether magnetic coupling exists in the core.This paper discusses the relationship of the two kinds of curves for different structural transformer.Conclusions are drawn that the B-H curve is similar to φ-i curve for single-phase transformer,the φ-i curve for symmetrical three-phase transformer is multiple B-H curve.The relationship of two kinds of curves for asymmetric three-phase transformer is deduced in this paper.