The University of British Columbia

Most common computer programs for time domain simulations of power systems calculate the state of the system step by step, either with fixed or with variable step size. They integrate differential equations by using numerical methods. Whichever method of integration is used, numerical errors in modeling power system impedances will arise, which may not be negligible in the presence of resonances. The problem of analytically describing these errors for complex circuits is analyzed, with particular reference to computer programs of the EMTP type. (C) 2002 Elsevier Science Ltd. All rights reserved.