An influence of a complex modernization of the DC traction power supply on the parameters of an electric power system

Urban and suburban public transport constitute basics of functioning of modern, urbanized metropolises. It is a comfortable, economic and ecological means of transportation. Thus, a stable and fast growth of this solution. One of its components is the power supply system. It should allow functioning of the whole transportation system, maintaining the following criteria: energy efficiency and modernity. These criteria have contributed to creation and modernization of power supply systems. Where it comes to DC systems, such an investment includes: replacing 6-pulse rectifiers with 12-pulse rectifiers and raising rated supply voltage. In this article, the authors have presented research results, based on measurements of electrical energy parameters before and after a modernization of a suburban transportation traction system. These parameters have been divided into two groups. The first consists of parameters mentioned in the EN50160 norm. Another group consists of parameters not mentioned in the norm. What has been presented are waveforms and graphs showing these parameters. In the final part of the article a discussion on reasonability of introducing new, modernized traction power supply system for suburban transportation has been performed.