Numerical integrator substitution

A continuous function can be simulated by substituting a numerical integration formula into the differential equation and rearranging the function into an appropriate form. Among the factors to be taken into account in the selection of the numerical integrator are the error due to truncated terms, its properties as a differentiator, error propagation and frequency response. Numerical integration substitution (NIS) constitutes the basis of Dommel's EMTP , which, as explained in the introductory chapter, is now the most generally accepted method for the solution of electromagnetic transients.