The Study On The Electric Transmission System Of A High Power AC Diesel Electric Locomotive

The paper aimed at the 5500HP AC transmission diesel locomotive jointly developed by Ziyang Diesel Locomotive Works and Zhuzhou Electric Locomotive Research Institute as its reserching object. By means of the discussion about the main technical parameters of the locomotive and its AC transmission control system,the comparison of the technical scheme and the analysis of the working processes,the paper eventually determined the main technical plan of this locomotive and its transmission control system.The first part of the paper presented the history and existing situation of the AC transmission technique in China and abroad and the advantage of this technique. The background of this project is mentioned here. The main reserching work of this paper is also introduced in this part.The second part mainly deal with the general technical parameters of this locomotive. Starting from the development of the Chinese Railway transportation and its requirement for the locomotive traction performance,the paper analyzed the main parameters of the locomotive such as locomotive horsepower,speed,traction effort,braking force. The traction and dynamic brake calculation of the locomotive has been made here. The starting and accelerating performance of the locomotive is also analyzedThe third part discussed the mode of the main circuit and the form of the inverter. The main circuit plan of the AC transmission system is also introduced here.The fourth part analyzed the intermediate DC voltage and its control principle and the technical parameter of the main parts in the AC transmission system. Several key technical problems such as parallel working of the AC motors,the wheel diameter difference under the Bogie-control mode,the AC motor-inverter matching principle are studied in detail. The principles to determine the electrical parameters are also discussed. The working process of the AC diesel locomotive on traction anddynamic braking service as well as the matching relationships and control principles of the electrical parameters are analyzed in detail.The fifth part introduced the main characters of the locomotive converter which has the water cooling GTO as its switching element.The sixth part discussed the working principle,control process of the locomotive computer control system. The logic control principle by locomotive computer and its control logic process are introduced. The control system for the electronic fuel injection of diesel engine on this locomotive has been introduced. The emphases is put on the way to realize the constant power control for the diesel engine by the electronic fuel injection system,and how to transfer the auxiliary power of the locomotive and how to modify the locomotive tractive effort to compensate its temperature swing as the calculation result of the tractive effort by Direct Torque Control is dependent on the temperature. The control mode of the inverter is introduced at the end of the paper.