Calculation of operation mode of outdoor lighting line with bilateral supply part 1
The electrical outdoor lighting grids are formed with a regard for their functional purpose. The present article draws the attention to the specific features of operation mode of an outdoor lighting line with a bilateral supply. This mode of operation is characteristic for main streets and circular roads. The article presents the method of calculating of the mode of such kind and the calculation itself that has been fulfilled on behalf of the outdoor lighting line with a bilateral supply described in the article. Luminaries with high pressure sodium lamps connected through electromagnetic ballasts were used as sources of light. The accuracy of parameters under calculation depends on the completeness of the source data. The calculations were implemented with the use of a program realized in MathCad. For each line phase the following mode parameters were defined: voltage in the circuit points, power, current, power loss and voltage drop on all segments of the line. The calculated data can be used for various purposes. Power magnitudes were determined for two points of supply and one can determine the power consumption provided that the time of operation of electric lighting is known. Estimation of the efficiency the mode on the basis of ensuring the necessary level of voltage at the luminaires was implemented. Active and reactive power of a luminary is determined by the voltage at the terminals of the luminaires. Magnitudes of power of luminaires located at different distances from the power source differ from each other. The voltage value has a significant effect on the electricity consumption values and on operating characteristics of a light source. With the use of the abovementioned program a line of outdoor lighting with a bilateral supply of any configuration can be simulated and different operation modes of a grid, viz. evening, night, dimming and other modes can be calculated.