Traction Power Supply System Of Trolleybus And Its Testing Research

With the acceleration of China’s economic growth and urbanization, cities are constantly expanding in both size and population, which brings about considerable pressures on urban traffic. Traffic congestion has become one of the major concerns in urban construction and development. Urban Public Transportation, with its unique advantages such as being intensive, efficient, energy-saving and environment-friendly, has been performing a very important function in urban public transport system. Developing public transportation, as a strategic choice to build a resource-saving and environment-friendly society, is vitally important and absolutely necessary since it can ease traffic congestion, transform the development mode of traffic.Trolley bus as an important part of urban public transport, in recent years started from recession to recovery, has received increasing attention. Traditional trolley bus power supply has problems of complex structure, poor reliability, urban visual pollution. On the basis, such as "one line one ground" type of trolley bus is proposed, and its traction power supply system is analyzed and designed, and a new protection scheme of traction power supply system is put forward.The thesis elaborates the "one line one ground" trolleybus scheme, analyzed in depth the traction power supply system. Combined with the trolleybus experiment line construction carried out in SWJTU Emei campus, the thesis put forwards the design scheme for the traction power supply system, and analyzes the rectifier transformer, rectifier, the voltage of rectifier in the system.The thesis introduces the fundamental principles of rectification technology, Matlab/Simulink is used to build the simulation models of 12-pulse and 24-pulse rectifier units. An analysis of the features of AC side harmonics and DC side harmonics and the 24-pulse rectifier unit produces non-characteristic harmonic. The thesis arrives at some important conclusions which can benefit not only the optimization design of traction power supply system for trolley bus but also the performance of rectifier units as well as the construction and re-construction of urban rail transport system.The protection of traction power supply of the trolleybus is also discussed in this thesis. A new protection method of new traction power supply is presented. In the thesis, the new protection principle and the fault type identification method are described in detail. Improved DC traction power supply system and protection method, with the new functions of identifying and distinguishing permanent fault and transient (non-permanent) fault, and thus is applicable not only to the trackless trolley for electric system and new urban rail transit line, but also to the transformation of the existing urban rail transit traction power supply system.