Field measurements, modeling, and analysis of power system harmonics caused by industrial customers

Due to problems caused by non-linear loads in a power system, a harmonic technical analysis on the hydroelectric generating units Illuchi 1 and 2 of the Electric Utility Company of Cotopaxi Province ELEPCO S.A., Ecuador, is performed in this project by means of industrial analyzers as well as software simulation. The analysis starts from harmonic distortion measurements on the generating plants and El Calvario substation. Then, simulations are performed including non-linear loads characterized as current sources in the east zone of the studied system by using a harmonic power flow to determine the industrial load causing the current fluctuations. The maximum values of THD are in the order of 5.4% and 3% in Illuchi 1 and 2, respectively, that are above the recommended values of IEEE Std. 519-1992. Based on these results and determined the cause, filters for 5^th and 7^th harmonic according to the IEEE Std. 1531-2003 are designed.