Modeling, Simulation And Application Research Of Balise System

As key equipment for fulfilling the ground-train point-mode information transmission process, the balise system provides timely and necessary information for railway traffic control and dispatching, thus its working conditions directly affect train operation safety. The ever increasing train operation speed has demanded even higher requirements for the safety and reliability of the balise system. However, few reports have been found with respect to the fundamental theoretical researches such as the electromagnetic characteristics and work principles of the balise system, which is a hidden danger to the Chinese fast developing railway. Therefore, this paper carries out the modeling, simulation and corresponding application researches to the balise system including downward exciting process and up-link process from theoretical level, which has crucial theoretical values and reality meanings. The main researching works are as follows:Aiming at the deficiencies regarding circuit principles and electromagnetic characteristics of the balise system, the paper implements the static modeling and simulation of the ground-train point-mode information transmission process by employing finite element method (FEM). The paper divides the balise system model based on FEM into three sections, i.e. the coupling coil, the exciting circuit and the receiving circuit, and also divides the whole process of train-pass-balise (TPB) into three areas, i.e. the dormant area, the operation area and the peak area. The static electromagnetic simulation is carried out to obtain the building process of the ground balise induced voltage and the spatial magnetic field distribution among the three areas. The up-link signal transmission process is used to prove the validity and correctness of the FEM simulation.Aiming at the limitation of the above FEM analysis and shortfalls of theoretical researches regarding the work principle of the balise system, the paper carries out the theoretical modeling and simulation of the dynamic TPB process of the balise system using electromagnetic theory. The mathematical expressions of balise induced voltage and its amplitude envelope are derived using corresponding electromagnetic laws. Through theoretical simulation, the paper analyses the magnetic distribution within the balise receiving antenna plane and the change law of the balise induced voltage amplitude envelope (BIVAE) in the TPB process, and reveals the relationship between the downward exciting transmission and the up-link transmission, through which the concept of effective range is proposed. The measured, theoretical and simulated results of the reference loop flux are used to validate the theoretical model.The paper carries out the performance optimization of the balise system based on the relationship between the two transmission processes. The influence of train speed to BIVAE is analyzed and based on that, the target and evaluation standard of the performance optimization are proposed. Then the paper carries out the optimization research from two perspectives, i.e. the balise mounting style and the mounting height of the on-board antenna, and by using Golden Section method, the optimized scheme of the system performance is obtained. Experiments verify that this optimized scheme can meet the adapting requirement to higher speed of the balise system. The feasibility of the performance optimization from the pitch angle of the on-board antenna is discussed, and a potential scheme is proposed.