Open AccessUnbalanced source identification at the point of evaluation in the distribution power systems
Author(s) -
Sun Yuanyuan,
Xie Xiangmin,
Li Peixin
Publication year - 2018
Publication title -
international transactions on electrical energy systems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.428
H-Index - 42
ISSN - 2050-7038
DOI - 10.1002/etep.2460
Subject(s) - upstream (networking) , electric power system , robustness (evolution) , identification (biology) , reliability engineering , computer science , sensitivity (control systems) , control theory (sociology) , power (physics) , downstream (manufacturing) , point (geometry) , engineering , electronic engineering , mathematics , telecommunications , botany , geometry , biology , biochemistry , physics , chemistry , control (management) , operations management , quantum mechanics , artificial intelligence , gene
Summary Three‐phase unbalance is one of the most important power quality problems in the power system. When the system is working under unbalanced conditions, more losses and heating effects will be induced, and the system will become less stable, which is harmful to both utilities and customers. The most important thing for a seriously unbalanced system is to find out the main unbalanced source to take proper measures to mitigate the problem. In this paper, a method is proposed to indentify the main unbalanced source at the point of evaluation (POE) in the distribution power systems. Two extreme cases are analyzed in the paper by assuming that the unbalanced source to be totally from the POE upstream network or downstream network. Therefore, 2 corresponding analytical formulas are derived to reveal the relationship between the POE voltage unbalance factor (VUF) and the current unbalance factor (CUF). A method is then proposed to determine the contribution of the unbalanced source at the upstream and downstream networks based on the comparison between the derived VUFs and the actual VUF. Sensitivity analysis is implemented to show the robustness of the proposed method. The effectiveness and validity of the proposed method is illustrated by the IEEE 13‐bus test system and IEEE 37‐bus test system. It is shown that the estimation error of the proposed method is generally within 5%.