Research On Real-Time State Monitoring Of Compensation Capacitor In Jointless Track Circuit

As the important part of ground-train continuous information transmission and the key equipment of train operation control system, joint-less track circuit(JTC) can achieve the train occupying checking, integrity checking and ground-train continuous information transmission. Among them, the compensation capacitor is an important equipment to improve the signal transmission quality of joint-less track circuit, whose failure will directly change the network structure of track circuit and affect the normal working of JTC, which will probably decrease the efficiency of train operation and endanger traffic safety. At present, the research at home for compensation capacitor state monitoring, in aspects of timeliness, has been unable to meet the requirements of high-speed development of Chinese railway. The centralized signaling monitoring (CSM) system of Chinese railway has achieved monitoring the state of track circuit round the clock, therefore, based on the data of CSM, this dissertation focuses on implementing the real-time state monitoring of compensation capacitor, by researching on the influence of compensation on the data of CSM. The work is of great practical significance and research value. The main work of this paper is as follows:l.For the transmission process of track circuit signal in adjusted state, based on the transmission line theory, the paper models the transmission process of main track circuit and small track circuit signal respectively and analyzes the effect of different compensation capacitor fault on the receiving voltage amplitude of main and small track respectively. The hierarchical clustering method is used to classify the receiving voltage amplitude of main and small track circuit receiver caused by the different compensation capacitor fault. The average distance from the original data to different kinds of centers is used to evaluate the clustering effect and the optimal clustering distance threshold is determined. The receiving amplitude of main and small track receiver are obtained from CSM and the distance from the sample to be measured to the center point of all kinds of compensation capacitor state mode is calculated to obtain the compensation capacitor state. Eventually, the compensation capacitor monitoring is implemented in adjusted state.2. For the transmission process of track circuit signal in shunted state, based on the transmission lien theory, the paper models the transmission process of small track circuit signal and analyzes the effect of different compensation capacitor fault on receiving voltage amplitude of small track circuit receiver. Simultaneously, the sub-features are extracted from the receiving voltage amplitude envelope of small tack circuit receiver by fitting, amplitude and information entropy analyzing, and a state monitoring method is proposed for the compensation capacitor on basis of the principal component analysis (PCA) and correlation method. The PCA is used to reduce the dimension of features and obtain the corresponding transformation matrix. The relevance similarity theory is utilized to develop fault recognition strategies to set the recognition threshold. Eventually, the compensation capacitor monitoring is implemented in shunted state.3. Combining with the characteristic of the monitoring method of compensation capacitor in adjusted and shunted state of JTC, the paper proposes a real time comprehensive monitoring strategy for compensation capacitor state and constructs the compensation capacitor state monitoring module. It is shown that the method combined the monitoring method advantage in adjusted and shunted of joint-less track circuit, can improve the accuracy of monitoring the compensation capacitor state.