The Research Of Switch Control Module Based On Distributed Computer Interlocking System

Against this background of railway signal equipment towards decentralize,miniaturization, high-speed, intelligent, This paper proposes a distributed switch controlmodule combined with distributed control technology, power electronic switch technology,fail-safe technology, safety analysis technology, etc. Distributed control method is applied tothe computer interlocking system compared with the centralized interlocking control mode tosave the cost and reduce the disconnection, mixed line fault，increase the reliability of thesystem. But the trackside environment is more special. So, the module should be more safety,reliability and anti-interference, at the same time module also need to have the characteristicsof small volume, intelligence and high real-time performance.The research of distributed switch control module belongs to the early stage in ourcountry. In this paper, the distributed switch module is researched in this situation. On onehand, thesis draw use action principle and design method of traditional switch control circuitfor reference. On the other hand, the paper also combined with design experience of computerinterlocking equipment.Firstly, this paper introduce the situation of development of the computer interlockingsystem, analyzes on the advantages of the distributed computer interlocking system, clearabout the significance of selected topic. According to the characteristics of distributedcomputer interlocking system and the functional requirements of the switch machine.Through the analysis of safety method, clear the risk source of the system. In order to knowthe relationship between system fault and single function fault, building Fault Tree. Throughthe allocation of system’s allow risk, get the module’s allow risk and clear the method ofhardware circuit and software. In the phase of hardware design, introducing the technology ofsafety and reliability, overall structure of the hardware circuit was introduced in detail. Theprinciple of the main control circuit, the indication acquisition circuit, current detection circuit,monitoring circuit and the communication circuit is analyzed. In thesis, the working principleof dual system hot spare and hot standby switching circuit is described and illustrated in detailalso. In term of software, through introducing related technology of software, coming up withthe requirements of software’s design. Introduce the principle and working process ofinitialization of MCU, synchronization, communication, control circuits and the indicationacquisition in detail.Finally, using the method of the Fault Tree analyze the safety of the module. Throughqualitative analysis and quantitative analysis of the module, fault probability of the top eventis obtained. Results indicate that the failure rate of the switch control module can meet therequirements of the system’s safety. The result of research provides the basic data and theoretical basis for the tracksideexecution unit’s further development of distributed computer interlocking system. Theresearch method can be applied to the rest of the trackside execution unit module.