Wavelet and multi-rate analysis for the simulation of electromagnetic transients in power systems

Abstract

This work illustrates a network equivalent multirate model based on Discrete Wavelet Transform (DWT) and Multi-Rate analysis (MRA). The processing structure operates as a multi-rate digital filter, decomposing signals and network into frequency sub-bands. This concept is applied in the time domain and adjusts the integration step during the simulation, it is implemented using signal processing theory, and filter banks and the network equivalents is a generalization of the Electro Magnetic Transient Program (EMTP) approach with three different integration rules. Finally two implementations of the proposed model are explained, the first tool is used for parallel processing but with loss of accuracy and the second model is based on the solution of linear systems in state space via Lyapunov equation.