The Research In Logical Control System Of Diesel Locomotive Based On PLC

The diesel locomotive is the mainly pulling force of the railway transportation of our country, which takes charge of thousands miles of strenuous railway transportation tasks for a long time and is playing an important role for the national construction and the development of economy.The technology of the diesel locomotive will be improved in all aspects with the development of railway transportation to the high-speed, heavy-loaded direction and the higher requirement for its quality, level and techanical innovation since the 21st centry. At present, most of the diesel locomotive still use the traditional relay and interlock to control in logical control system. And this kind of control systrm has too many contacts, complicated connect, miscellaneous control circuit, badly reliability and inconvenient repairment.Even some contacts will be burned-out by running under large electric current, which cause the electric fault rate of the locomotive to remain high, and influence the safty and efficiency of the locomotive directly. So how to improve the logical control system of diesel locomotive, enhance its reliability, simplify the control circuit is becoming an urgent task to overcome.The huge use of PLC in industry control system makes it possible to improve the logical control system of diesel locomotive. This thesis combines the logical control system of diesel locomotive with the application technology of PLC, replaced the various traditional relay to set up a logical control system based on PLC. It introduces how to use PLC to replace the tradional relay and contact , which is in order to enhance the reliability and stability of system;It is designed by module , which makes it possible for the control system to have a very strong expansion ablity and can realize the communication with the computer intelligence; It uses the professional PLC equipment,which makes the control system has much lower cost but higher performance, and meets the demands of domestic national conditions; It also could be used as a diesel locomotive logical control teaching laboratory bench in a university by some improvement, which could give a good performance to interact with students and get the ideal studying result. All of these make this control system to be a typical mechatronic automatic control system.