Discrete-Time Fourier Series to simulate transient over voltages in power systems

Abstract This paper presents a methodology based on the Discrete-Time Fourier Series (DTFS) to calculate transient over-voltages in power systems. The proposed algorithm determines the time window with sufficient width to allow the time constants of the transients to decay to a small value. This method is simpler than the traditional numerical Laplace transform (NLT) and does not require parameters adjustment to obtain accurate results. The test case is based on a study to calculate Transient Over-Voltages (TOV) for 138 kV transmission lines in British Columbia, Canada. To assess the accuracy of the results, the DTFS solution is compared with the traditional NLT solution with optimized parameters and with the frequency-dependent time-domain models: fdLINE (JMARTI Model) and Universal Line Model (ULM).