Research Of The Electronic Unit Pump Fuel Injection System Of HXn5Locomotive

In recent years, China’s railway continue to progress in the development of high-speed and heavy-load, the requirements are also getting higher and higher. In order to meet the market demand, our CSR Qishuyan Locomotive&Rolling Stock Co. Ltd. is in cooperation with the U.S. company GE develope and manufacture China’s largest power AC drive diesel locomotive at present, that is HXn5diesel locomotive. The core component of the locomotive-diesel engine, is the world’s most advanced GEVO16low-emission four-stroke diesel engine. The fuel injection system of this diesel engine is composed of electronic unit pump, solenoid valve and the porous injector and some other advanced structure and technology. In this paper, fuel injection pump and its solenoid valves, injector in the fuel injection system are studied. Carried out research work in the following areas:First of all, the completion of mapping the main parts of the HXn5locomotive diesel fuel injection systems---the fuel injection pump and the injector, and then complete the design of construction drawings. On this basis, with the GT-Fuel software the simulation model of diesel engine fuel injection system is established. And analysis the structure and performance of the system with the use of powerful post-processing features of the GT-Post software. Obtaine the peak pressure of high-pressure fuel, law of injection, the lift of solenoid valve and the needle valve, and some othe important fuel system performance parameters. Compared the parameters of fuel system with the same type of domestic locomotive diesel engine, we find that the performance of introduced locomotive diesel engine fuel injection system is superior, and we also find out the inadequacies of the domestic locomotives through it.Secondly, with in the GT-Flow the simulation model of solenoid valve in this injection system is established. The solenoid valve is the key components of diesel fuel injection system performance, its performance directly affects the injection performance of the fuel system. Therefore, study and analysis the characteristics of the solenoid valve is quite necessary. In this paper, two main aspects that solenoid valve drive current and the solenoid valve spring preload are analyzed, ultimately determine the reasonable parameters in order to achieve the requirements of the rapid response to the solenoid valve.Finally, build a single-cylinder model of the diesel engine by using GT-Power software, and the single-cylinder engine is simulated by use of the selected parameters of solenoid valve. Through the simulation analysis, the fuel injection system has a greatly affect on diesel engine performance. At the same time with the comparison of experimental datas the solenoid valve parameters is reasonable.Through the work above, master the basic characteristics of the electronic unit pump and solenoid valve of HXn5locomotive diesel engine fuel injection system. It is the first time in China, to carry out systematic research and analysis on this fuel injection system, in order to pave the way for better absorbing international advanced technology. At the same time it provides a reference for improving the fuel system of domestic locomotive, also provides the valuable experience for domestic counterparts.