ANALYSIS OF METHODS FOR CALCULATING THE RELIABILITY OF RAILWAY AUTOMATION SYSTEMS WITH ELECTRONIC COMPONENTS

Abstract

Testing of electronic products of railway automation involves assessing the indicators of their functional safety and reliability. Reliability standards are very high. Confirmation of these  indicators is mostly performed by the calculation method [8]. For this  purpose, the branching technique is applied. The initial data for the calculations are the reference failure rates of the elements of the product under study. In the industry  methodology, it is recommended to obtain these failure rates from the time directory, or other available sources. Directories of the late twentieth  century are not relevant today. Among the current reference books is MIL-HDBK-217 F. Military handbook. Reliability prediction of electronic equipment. 1991, published in the United States. This guide is used by the vast majority of domestic developers of railway automation products. However,  there are certain methodological problems that hinder the use of the methods of the above document. In particular, the methods of the late twentieth century provide reference values of failure rates, which  characterize the maximum load on the element. The actual calculated values of failure rates will be significantly lower than the maximum. The  reference values of the failure rates, which are given in the American directory, reflect the minimum possible values. In this case, the actual  calculated values of failure rates will be significantly higher than the reference. It is obvious that the joint use of the  railway industry methodology and the American reference data on failure rates is not correct. In addition, the American method operates with more parameters. A way out of this situation is proposed. If the researcher uses the American value, he is obliged to use as much additional data as possible. Not all such data can be correctly used in the calculations of domestic developers and researchers. Therefore, a comparative analysis of the calculation formulas from the two above sources. Identical parameters and certain differences are indicated. Conclusions are made on the adaptation of the ratio of the American source to domestic requirements.