Research On Winding Loss Of High-Frequency Magnetic Components

Magnetic components play an important part in switching mode power supplies. They areplaying an important determinant factor in the performance and stability of the switching modepower supply. In the switching mode power supplies, the volume and weight of magneticcomponents account for a large proportion. With the continuous development of powertechnology and the continuous improvement of the operating frequency, it helps to reduce theproportion of the entire circuit of magnetic components. However, the high-frequency effect onthe winding of the magnetic components is more and more obvious, leading to the windinglosses increases. This paper to reduce winding loss as a starting point, studies the influence of thehigh-frequency effect on the conductor loss, and the design of the parallel windings of the planartransformers. Finally,the article analyzed the winding loss in the inductors.This article begins with the Maxwell electromagnetic field equations, the loss caused by theskin and proximity effects of the thin copper foil were studied. The study concluded that the totalloss of the thin copper foil is equal to the set of the sum of the loss in the skin effect andproximity effect work alone. Analyzed in the case of one-dimensional, thick conductor dividedinto two layers of equal thickness of thin conductor parallel and the conductor loss could not bereduced. The thick conductor divided into parallel thin conductors, in the insulating layer due tothe presence of alternating magnetic flux, it will lead to loss increase. In one occasion, in order toincrease the current carrying capacity of the windings, it is usually used parallel windings.However, due to high-frequency effects may lead to parallel winding current is not sharedequally. This article analyzed the cause of the uneven flow in parallel windings, and verified bythe two-dimensional electromagnetic simulation software from the current density distribution.This paper analyzes the air-gap effect, bypass flux and edge effects in the design of theinductor. The conclusion is that with the air gap changes in the column position of the coreWinding loss influenced by the bypass flux is not the same. The conductor near the air gap isaffected by the fringing flux will generate a lot of eddy current losses, and verified by the finiteelement analysis software.