Dynamic Event Analysis using Synchronized PMUs via 220 V Wall Outlets

This paper presents the dynamic analysis results of a system event in Thailand power network using a wide-area monitoring system based on synchronized phasor measurement units (PMUs). The salient feature of the proposed monitoring system is the convenient installation of PMU at 220 V wall power outlets. The event considering here is a 80 MW load transferring from Thailand to Malaysia systems through a weak 115 kV tie- line. To perform load transferring, a synchronization between both systems is required. This causes a problem of frequency oscillation in a southern area of Thailand. Besides, this event severely excites the inter-area oscillation in a 230 kV tie-line between central and southern areas of Thailand. Analyzed results based on discrete wavelet decomposition and short-time Fourier Transform provide valuable information of the system dynamic behavior in both frequency and time domains.