Design And Implementation Of Axle-counter Inspection Equipment For Track Circuit Bad Shunting In Railway Station

Bad shunting of track circuit is a conundrum for railway traffic and electricity department over the years. Railway technology department has never interrupted the study of this problem. Such as adjust the send voltage of existing track circuit, or using the electronic high-voltage pulsed track circuit. But the researches of this direction have not got both safe, reliable, practical and economic solutions. Only giving up track circuit and using axle-counter, can we completely solve the problem caused by bad shunting of track circuit.According to the special situation of bad shunting in railway station, and combined with the inspection of railway section principle, we have designed a new kind axle-counter equipment. The control object of axle-counter is a single track section. This decentralized control approach makes the axle-counter equipment miniaturization. The control of each railway section is independent. One axle-counter failure will not affect the control of other sections. We use the current-loop to establish the axle-signal communication channels, between the outdoor devices and indoor devices. This change let the outdoor axle-counter devices can work without microcontroller. So we can greatly simplify the axle-counter equipment. we improve the anti-jamming performance and make the reliable communication distance reach 10 kilometers.When design the system, we take the high security and high reliability requirements of the railway signaling equipment into account. We have taken several methods to ensure the safety and reliability of the equipment. Hardware design:Main control unit and axle-count unit use the "two out of two" security structure; Using the dynamic drive safety I/O circuit. Software design:Give full consideration to the non-normal clearing of track section; Check the important information with redundancy method; Identify the security side of critical software. Fault detection and safety-oriented design:Using software to make a very comprehensive inspection of the hardware state. Fault detection includes:Micro-controller self-test; Peripheral chips test; CAN communication test; Detection of the axle-signal transmission channel; Relay test. The corresponding fault code tips will be given when the fault is detected.We overcome these technical problems, optimize the hardware and software design, improve reliability and stability of the system, substantially reduce the cost of the equipment. All this will laid the foundation for greatly promoting the application of the axle-counter device.