Анализ погрешностей расчетов нагрузочных потерь электроэнергии в проводах воздушных линий электропередачи

Abstract

The errors introduced in calculations of load-induced loss of electric energy in the wires of overhead power lines due to omitting the effect of meteorological factors are analyzed. The load loss in the overhead power line wires depend directly on the wire temperature, which, in turn, depends on the wire current, ambient air temperature, and various meteorological factors, such as solar radiation and wind velocity and direction. The methods through which these factors can be taken into account are rather intricate in nature and inconvenient for use in engineering calculations. In view of this, there is a need to analyze the cumulative effect of all factors, to evaluate the errors arising from neglecting the influence of meteorological conditions, and to identify the input data boundaries within which the calculations can be carried out according to a simplified procedure. Load-induced losses of electric energy in the overhead power line wires having standard cross-sections are calculated for different combinations of current density in the wires, load curve shapes, and meteorological factors characteristic for some cities of Russia. The error of the electric energy loss calculation carried out without taking into account the actual wire temperature is estimated. The error in the load-induced loss of electric energy in the wires of overhead power lines calculated assuming the wire temperature equal to the monthly average air temperature is presented as a function of the daily temperature fluctuation amplitude. The ranges in which the load-induced loss of electric energy can be calculated at satisfactory accuracy without taking the actual wire temperature into account are defined. Recommendations on calculating the load-induced loss of electric energy in the wires of overhead power lines are elaborated.