Hybrid Automata Supported Method For Development Of Positive CBTC On-board System

In communication based train control (CBTC) system, traditional on-board equipment can only monitor train speed by receive movement authority, which is sent by track-side ATP equipment. The functions of block control, route control and track-side equipment control are also completed by the track-side equipment. This leads to the problem that the on-board equipment cannot protect the train by itself, and the whole system is rely too much on track-side equipment. Meanwhile, because of complexity of the architecture and the function of track-side equipment, the CBTC system cannot fit for some special lines which require simple architecture of track-side equipment.This thesis focus on the development method of positive on-board equipment in CBTC, specifically works show as follows:1. Based on the basic framework of CBTC, this thesis studies the division of safety protection function of the system, and then proposes the concept of positive on-board equipment and the structure of the system. It also designs the function of positive on-board equipment;2. This thesis analyzes the hybrid characteristic of positive on-board equipment, and studies the development method base on the theory of hybrid automata;3. This thesis models the function of emergency brake speed calculation, emergency brake intervention speed calculation, service brake speed calculation, permitted speed calculation, brake implement, route request and movement authority calculation, which consist the hybrid automata model of positive on-board equipment;4. With the use of MATLAB, this thesis simulates and implements prototype system of positive CBTC on-board equipment. In calculating performance, the function calculation demand of the prototype system is only36.7MIPS; in functional, positive on-board equipment re-combines the function of over speed, protection and movement authority calculation.This thesis shows that positive on-board equipment is a typical hybrid system, and the theory of hybrid automata is suitable for modeling this hybrid system. It also proves the feasibility of positive on-board equipment, which can improve the intelligent safety protection ability of on-board equipment. Positive on-board equipment will decrease the load of track-side equipment and increase the application range of CBTC.