Assessment of Balanced Reliability of Restored Electricity Sources in Distribution Networks Taking into Account Typical Graphics of Generationand Consumption

Abstract

The article focuses on the location of centralized sources in providing a balance of power in distributive networks with distributed generation. The method of estimating the timetable of non-consumption of electricity to consumers is proposed, which is caused by sudden failures of the ES (electrical system) elements, the main equipment of the DES (dispersed energy sources), as well as the discrepancy, from the natural causes, schedules generated by the DES, declared.

The article suggests a combined method that, unlike known ones, takes into account the daily load schedule and changes in the electric power transmission scheme depending on the operation modes of dispersed sources. It has been experimentally established that the proposed approach makes it possible to increase the adequacy of the estimation of balance reliability by combining methods for estimating reliability and periodically refining the initial data with the help of geoinformation systems.

The presence of IDE in the electricity supply system has both positive and negative effects. Among the positive ones, it should be noted a decrease in electricity consumption during the day. Negative is the need for their reservation by centralized sources of energy, since IDEs without means of accumulation of energy cannot provide the stated schedule of power delivery due to the difficult predicted weather conditions. The results of calculations on characteristic load / generation graphs indicate the need to keep in reserve the power that would cover up to 40% of the total electricity consumption.

Considering these factors, using the probability theory methods and the decomposition principle, an expression was obtained for evaluating the lack of electricity in the distribution network with the DES. The probability of failure of individual elements of the ES, as well as the failure of dispersed sources and inconsistency of their generation schedules for a given time point are taken into account.

It has been experimentally established that using the power generating and consumption capacities, as well as power supply schemes for certain moments of time, it is possible to adequately assess the timetable for the lack of electricity for consumers, the reliability of the balance sheet, as well as the schedule of the required power reserve of the centralized source for ensuring the balance reliability of the ES, that is, consumer electricity supply and operation of the DES.