Improving the reliability of the relay automation system for power facilities

[摘要] The main reasons of the false (incorrect) operation of the microprocessor relay protection system are analyzed in the article. The methods of increasing the reliability indicators of the relay automation system are presented. Analysis of statistical data submitted by PAO Rosseti showed that the probability of failure-free operation of microprocessor relay protection systems is not lower than 0.998. Increasing the reliability of microprocessor protection systems does not dictate the revision of the Electrical Installation Rules, but requires the use of high-quality cable products with normalized technical characteristics, the transition to a digital data transfer format with the limitation of the number of variables fed through one serial channel. Exemplary upper and lower bounds are established for the cost of improving the reliability of the microprocessor system. For example, reducing the failure rate by half will require increasing the capital costs of protection from electromagnetic interference by about (3-4) times. Preservation of the reliability level of the microprocessor system in the process of operation is possible only if the planned measures are taken to assess the electromagnetic situation. As shown by statistical data, the most likely cause of incorrect operation of relay automation is atmospheric phenomena (lightning). Therefore, at the stage of estimating the electromagnetic state, it is necessary to pay attention to the state of the earthing system, and the fault diagnosis is most rationally performed by the half-division method, considering the probability of failure-free operation.

[发布机构] RiK-Energo Ltd, 15, Tarasova St., Chelyabinsk; 454048, Russia^1;Gmbh Anvilex, Enderstrasse 94, Dresden, Germany^2

[效力级别] 工业技术

[关键词] Digital data transfer;Electrical installations;Electromagnetic situation;Microprocessor protections;Microprocessor systems;Probability of failure;Reliability indicators;Upper and lower bounds