ASSESSMENT OF RELIABILITY PARAMETERS OF POWER SUPPLY SCHEMES IN TECHNICAL AND ECONOMIC CALCULATIONS

The relevance of the study lies in assessing the reliability parameters of power supply schemes with transformer substations with various redundancy options – at medium and low voltage – relative to consumers of low-voltage switchgear. The purpose of this article is to study the reliability parameters of circuits with 10/0.4 kV transformer substations. The paper examines the reliability of the power supply system for the following circuit options: without redundancy; with medium voltage (MV) redundancy; with low voltage (LV) redundancy; with double redundancy: with redundancy of the MV circuit and the LV circuit. The condition for the rational construction of the power supply circuit is the smallest number of transformer substations and, accordingly, distribution transformers, while maintaining a load factor of 0.8. When comparing the obtained dependencies, it was found that the highest mean time between failures, equal to 25.641, is achieved with double redundancy, and the lowest, equal to 5.435, is achieved without redundancy. The payback period for commissioning the scheme options was determined, taking into account the inflation index. Based on the results of the calculations, it has been determined that the scheme with redundancy at the low voltage level has a payback period for the equipment of 8.52 years. The scheme with two single-transformer substations without redundancy has a payback period for the commissioning of equipment of 7.75 years. The payback period for the double redundancy scheme equipment is 8.81 years. The results showed that the failure rate parameter has a minimum value of 0.039 failures per year for the double redundancy scheme (HV and LV circuits) and a maximum value of 0.368 failures per year for the non-redundant scheme. When comparing schemes with backup at the low voltage level and backup at the high voltage level, the failure rate parameter differs insignificantly (0.042 and 0.043 failures per year). The research results can be recommended for use in the design of power supply systems and in conducting a feasibility study to select the optimal circuit option, taking into account its reliability parameters.

power supply system, ring scheme, reliability logic scheme, power source, failure rate parameter, redundancy, double redundancy, technical and economic indicators.

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2026-03-30