A complete model of a single layer air-cored reactor for impulse voltage distribution

A numerical method developed for the computation of impulse voltage distribution in a single-layer air-cored reactor is discussed. The method uses lumped parameters with mutual coupling as suggested by H.W. Dommel (IEEE Trans. Power App. Sys., vol.88, p.388-99, 1969) for transmission lines. The capacitance coefficients have been computed by the charge simulation method. The method includes the mutual inductances, the mutual capacitances, the winding resistance, the capacitance to ground and the insulation resistance. Three implicit methods, trapezoidal integration with damping, trapezoidal integration, and backward Euler, have been used to obtain the companion network. Three test cases are examined: published one to test the numerical method and two measured cases to show the agreement between the computed and the measured results for the actual reactors. The effect of the parameters on the solution has been studied. The method is simple since it involves only the solution of a system of linear equations