High reliable unilateral inductive axle counting sensor system and applications

This paper proposes a new high reliable unilateral inductive axle counting sensor prototype based on eddy-current principle. It could send out strong analog signal several kilometers away without any trackside or inner magnifying circuits because of its special open flux magnetic structure and signal processing method. The operational principle of the sensor is studied with modeling as well as the validation by experiments in labs. Signal processing is implemented to extract the information of train's occupation including the vehicle speed, traversing direction, wheel diameter and so on. It also conforms to the requirement of the Safety Integrity Level 3 standard. The performance of this proposed sensor is discussed with different operational conditions for the future work.