Electrical System Study Of Type GKD_3B Diesel Locomotive

Type GKD_3B diesel locomotive is an electric transmission shunting locomotive and small transfer locomotive provided to customers in and beyond railway. It has type 12V240ZJ diesel engine, and loading power is 2000kW.The locomotive adopts AC-DC transmission. The three phase AC generated by a main generator driven by diesel engine is rectified, and transmitted to six paralleled DC traction motors, and then the traction motors dirve wheel running via drive gear. The mian generator adopts brushless excitation.Microcomputer control system is used for the locomotive. Microcomputer system adopts modular design, and multifunctional real time control system with the core of type SIMATIC S7-200/CPU226 PLC. It has powerful function, good performance, and reliable operaion, with constant power excitation regulation, lowly constant speed control, dynamic brake and self-load function, and can realize logic control of the locomotive. There is a large colour display screen for the system, which can not only show the operation status parameter of locomotive and diesel engine, but also show failure information of each system on the locomotive. In addition, it has man-machine conversation function. This control system is in ahead of these types locomotive.This article introduces in detail about main operation principle of locomotive eletric system, each main electrical equipment and device, and microcomputer system, and analyses the eletric circuits such as main circuit, excitaion circuit, auxiliary circuit, control circuit, lighting circuit and so on. Furthermore, it forecasts the application situation and the future of this type of locomotive.