Study on the EMI impact over the safety of railway signaling and case analysis

摘要

Focusing on relationship between EMI and the safety of railway signaling, this paper proposes a quantitative analysis method about the EMI consequence over the safety. At first, on the basis of traditional reliability analysis method, FTA, the railway signal equipment is appropriately divided into several independent parts or components, and the fault probability is calculated under the condition that the component performance is affected by EMI. Next, based on the AHP, the weight of risk occurrence degree for each fault mode is inferred, and each fault mode is properly classified into the fail-safety side and fail-danger side to obtain the probability values of the component. Then, owing to the influential mechanism of EMI on signal equipment, ß-factor based CCF is introduced to analyze the posteriori probability by BN. Therefore, compared with the original probability data without EMI, the quantitative result clearly shows the influence extent under the EMI since it determines the equipment's SIL. Finally, taking ZPW-2000A track circuit as the typical case, the impacts of EMI are analyzed based on this procedure, and the detailed safety data of transmitter and receiver are calculated and discussed, the result preliminarily proves the feasibility of this quantitative analysis method.