Development of calculation methods for additional electrical power losses during transportation

The paper describes additional electric power losses which are not considered in traditional calculation methods for electric power losses in electrical grids. They include losses produced by high harmonic currents together with additional losses produced by fundamental frequency currents due to their unbalance. The Russian regulatory documents regarding the account of electric power transmission losses, do not consider the additional losses. The authors have obtained the mathematical description of electrical grid regimes and its implementation procedure, considering the additional electric power losses. The research allowed solving a number of important practical problems: · to determine the value of additional electric power losses factor (increase of specified losses on account of additional ones); · to identify the structure of losses due to fundamental and high harmonic currents; · to estimate the influence of fundamental frequency current unbalance on the level of losses. The developed approaches were tested on more than two hundred 110 kV overhead transmission lines (OTL). The software package for calculating additional electric power losses is used in two electric power systems of Russia.