An Improved Method of Calculating the Power Generated in an Inductively Heated Load

Normally, coil and load end effects are neglected when calculating the power generated in an inductively heated load. Empirical correction factors are used to account for the effects of leakage flux. In this paper, the coil and load are approximated by a short current sheet and an infinitely long conductor. The resulting load power distribution is determined analytically for a cylindrical geometry. A correction factor that can be incorporated directly in the classical expression for load power is then derived in closed form. This factor describes the axial distribution of power in the load and inherently includes the effects of leakage flux. Numerical values are given in normalized form for a wide range of coil-load configurations. The accuracy of the method is illustrated by comparing predicted and experimental values of load power. The improvement relative to the classical methods is discussed.