연구홍보포털

논문 초록 (Abstract)

BACKGROUND/OBJECTIVES: Induction heater for electric vehicle have skin effect due to the influence of high frequency. And the influence of the skin effect, which is an AC loss, must be reduced. METHODS/STATISTICAL ANALYSIS: Reducing the skin effect is to alleviate the magnetic saturation of the workpiece surface. When magnetic saturation occurs, the magneto-resistance rapidly increases, so a design capable of mitigating the magneto-resistance is required. FEM analysis was performed to analyze the skin effect. If the magneto-resistance increases, the amount of magnetic flux leaked will increase, and the amount of leakage is checked by deriving inductance. FINDINGS: Magnetic saturation is related to magnetic reluctance. Magnetic reluctance is inverse proportion to the cross-sectional area of the workpiece through which the magnet passes. And magnetic reluctance has an inverse proportion relationship with inductance. When the cross-sectional area of the work piece was increased to reduce the skin effect, the total inductance increased, but the amount of leaked inductance also increased. The increase in leakage inductance acts as a loss, not heat generation of the work piece, and means an increase in the amount of leakage of magnetic flux in the work piece of the induction heater. The amount of leakage inductance increased to reduce the skin effect, and when the amount of leakage inductance was reduced, the skin effect increased. In this paper, about 11kW class induction heater was analyzed and the increase in leakage inductance was analyzed for the total inductance according to the surface of the workpiece. In addition, the trade-off between skin effect and leakage inductance was analyzed. IMPROVEMENTS/APPLICATIONS: The optimal design considering leakage inductance and skin effect reduces the volume of induction heater and can be applied to shielding design of induction heater.