TY - JOUR ID - 4373 TI - Power System Thévenin Equivalent Estimation Based on Phasor Measurements JO - Scientia Iranica JA - SCI LA - en SN - 1026-3098 AU - Alinejad Osbouei, Bahman AU - Kazemi Karegar, Hossein AD - Faculty of Electrical and Computer Engineering, Shahid Beheshti University (SBU), Tehran, Iran Y1 - 2018 PY - 2018 VL - 25 IS - 6 SP - 3559 EP - 3568 KW - Thévenin equivalent KW - Phasor Measurement Units (PMU) KW - Triangulation method KW - Phase drift KW - Slip frequency DO - 10.24200/sci.2017.4373 N2 - This paper presents a novel algorithm based on phasor measurements to online estimation of power system Thévenin Equivalent (TE) from a generator terminal. Three consecutive phasor measurements of generator terminal voltage and current are used to estimate the system TE. In a real network, system frequency deviation from its nominal value will produce some phase drift in consecutive phasors reported by Phasor Measurements Units (PMUs). To correct the phase drift and synchronizing the reported phasors to the same reference, an improved triangulation method is developed. The improved method uses a virtual vector in its structure. Using this vector alleviates the negative impacts of improper data resulting from noise or disturbances which make the simple triangulation method to be useless. The algorithm is tested on standard NE-39 network and is implemented in Shahid Beheshti University (SBU) protection laboratory to verify the results in a practical area. The obtained results show that the new method can efficiently estimate the  in online mode in steady-state and transient conditions. UR - https://scientiairanica.sharif.edu/article_4373.html L1 - https://scientiairanica.sharif.edu/article_4373_7bebdd06b0cdd78d655a8a4100f0d652.pdf ER -