| Popis: |
Rural networks are characterized by a large length and low load density. In the country, there are problems with the reliability of electricity supply to agricultural enterprises and the uninterrupted operation of electrical equipment. The average duration of consumer outages is up to 100 hours annually. In Western developed countries, it is statistically defined as an acceptable state of electricity supply, when for a medium- voltage network during the year, the total duration of interruptions is in the range of 15-60 minutes per year. The permanent functioning of the Russian agro-industrial complex is impossible without reliable and stable operation of rural electric distribution networks. (Research purpose) The research purpose is in studying the impact of electricity losses on the reliability of electrical equipment in the rural power grid of 0.4 kilovolt. (Materials and methods) The methods of ensuring reliability include: design features of the system, reliability of electrical equipment; provision of backup power, system management tools, organization of operation. The reasons for the decrease in reliability were: equipment failures, errors of operating personnel, excess of resource capabilities, deviation of the actual operating conditions of the equipment from the calculated ones. (Results and discussion) The article considers the issues of additional electricity losses in the low- voltage network of 0.4 kilovolts on the example of the power supply of an agricultural enterprise, caused by the flow of reactive energy. The article presents graphs of phase voltages and power consumption. Authors conducted experimental studies in a network of 0.4 kilovolts. The article presents the calculated reliability indicators of electrical equipment at an agricultural enterprise. The increase in reliability when installing a compensating device in the 0.4 kilovolt network are described. (Conclusions) The increase of reliability of electrical equipment is revealed, the probability of failure operation of the electric motors decreased by 3 percent; the probability of failure operation of the electric motors decreased by 19 percent; reducing the failure rate by 15 percent; decrease in failure rates by 14 percent. |
