Analyzing the Impact of Sodium Discharge Lamps Inrush Currents on the Street Lighting System and Electric Network Quality

The amount of electricity consumed for lighting purposes is growing rapidly, despite the development of energy-efficient lighting system technologies. According to numerous forecasts, in the nearest decade, the share of global electricity consumption for lighting needs will reach up to 40% of the total consumption for household and administrative needs. The general trend of technological development to reduce energy consumption and increase the efficiency of its use additionally emphasizes the relevance and necessity of studying various scenarios for upgrading the existing lighting networks and increasing their efficiency by shifting to more high-tech solutions. Gas-discharge sodium lamps are commonly used for street lighting because they have a relatively long service life and are quite versatile in operation. The starting current of gas-discharge sodium lamps used in street lighting networks is an important parameter, since it directly affects the lamp performance and service life, as well as the overall efficiency of the lighting system in which these types of light sources are used. A high starting current is required to ignite the gas inside the lamp and generate light. If the inrush current is too low, the lamp may not turn on at all, or turn on very slowly, which leads to flickering and a decrease in brightness. On the other hand, if the inrush current is too high, it can damage the lamp or even the entire lighting system. The purpose of this work is to study the effectiveness of using sodium gas-discharge lamps as the main light sources in street lighting networks and to determine the feasibility of shifting to more high-tech LED lighting technologies. The results of measurements of starting currents of street lighting luminaires with sodium gas-discharge lamps of an existing administrative building are presented. In carrying out the study, the structural, mathematical, and instrumental methods for analyzing the street lighting network electrical parameters were used. The study results and the accomplished analysis confirm the need to take into account the street lighting systems starting currents, indicate tangible negative effects of the start-up control equipment, which lead to an increase of the current through the zero conductor even with a completely balanced load, as well as noticeable current waveform distortions, which entails problems resulting in a deterioration in the quality of electric network parameters.