The Research And Design Of The Chain Control Logic Of The Main Tram Track Based On PLC

In recent years, the speed of the urbanization expedite obviously and the continuous expansion of urban population,combining with the rapid development of automobile industry in urban traffic congestion, the situation of environment is becoming increasingly serious.So develop a low energy consumption vigorously, less pollution, large capacity of urban rail transit has become one of the effective means to solve the problems of the environment, traffic and city.In this thesis modern trams become the main choice of small and medium-sized city passenger transport with its economic characteristics such as environmental protection and the moderate and comfort traffic.At the same time,it is also the extension and supplements of the big city metro light rail and other large capacity and rail transit, main switch control system as the main part of modern tram system is the key run line equipment to ensure the tram to run safely and efficiently. So, the main research and explore of the switch control technology has great significance to promote the development of modern trams science in our country.Main line switch control system's main function is to switch area ground signal equipment interlocking control, to ensure the safety of train and efficient through the switch area. In this thesis, combined with modern tram main driving demand and operating environment of conditions and the urban road traffic restriction factor, proposed by programmable controller(PLC) as core controller switch control system, the main modern tram rail interlock control logic of the control system is studied and designed.In this thesis, it analyzed the actual characteristics and traffic control requirements of tram. On this basis, it also decorated the signal equipment on the wayside reasonably which prepared for improving the driving safety and operational efficiency. Then it designed a kind of control method which can realize the automatic interlock control of the switch. Automatic interlock control mainly use the function named two-way communication and speed positioning of the inductive communication loop. During the train get close to the bifurcation, the control host of wayside and the terminal which installed in the tram will execute information interaction so as to carry out the interlock logic operations to the ground signal equipment and complete the automatic precise control of the switch. At the same time, the automatic interlock control mode, the remote control on-board and the ground control can switch each other rapidly and flexibly so as to ensure driving safety when an emergency occurs. This control method is simple and safe and can reduce the labor intensity of the drivers and control center attendants. On the basis of this kind of control method, it designed the overall structure of the switch control system based on PLC, then designed a kind of signal display method which can control logic closely and a interlock switch area control logic which can improve the efficiency of operations greatly under the premise of ensuring the safety of operation. And finally achieved the software programming to the interlocking control logic. The specific contents are as follows: First of all, it expounded the development of the trams, and discussed the topic purpose and significance of this thesis from several aspects, introduced the application situation of the modern trams at home and abroad, and also introduced the search status of the tram signal system at home and abroad, also the paper introduced the programmable controller technology.Secondly, based on the further study of the characteristics of the main modern tram operation and business processes, it analyzed the main switch control system functional requirements; did the selection and layout of the main rail area signal equipment and finally determined the key technology solutions such as the host settings, mode switch control. With the PLC as the interlocking logic processing host, it designed a kind of interlock switch area control logic which give attention to both the efficiency and safety.Then, according to the functional requirements and technical plans it put forward, the interlock control logic of the main switch control was finished which using STEP as the development platform, ladder diagram programming language as the development tools, using a structured software design method. In order to make the simulation test facilitate, it designed the interlocking PC monitoring software based on WinCC.Finally, it did the simulative debugging to the specific function of switch interlock control logic which using the PLCSIM simulate the real PLC hardware system, the WinCC interlocking PC man-machine interface as the test platform, and the debugging results prove that the interlocking control program based on the PLC can achieve accurate need of the interlock logic control function.