Considering the reliability of gas supply to power plants in the analysis of electric power system adequacy

Abstract

One of the promising directions for further development of the methodology for investigating and ensuring the reliability of energy systems is the consideration of integrated energy systems. This is caused by the need for the adequate reflection of their joint operation. Previously, the authors proposed several methodological approaches based on "node," "system," and "evaluation" to assess the adequacy of an electric power system when this is operating jointly with a gas supply system. In that case, the focus was made only on high-pressure gas supply systems (simplified calculation). This work aims to consider not only the high-pressure gas systems, but also to take into account the influence of lowpressure gas systems (refined calculation) on the adequacy of electric power system. This approach appears to be more technologically advanced and corresponds to the real conditions of the functioning of integrated power systems. The studies were carried out using the “node” approach, its reference calculation being the most accurate one. The methods applied in the research are probability theory and mathematical statistics: a particular theorem on the repetition of experiments (Bernoulli's trial), calculation of probability distribution series, theorems of addition and multiplication of probabilities. A comparative analysis of reference calculations of the electric power system adequacy was carried out for simplified and refined connection schemes in the gas system (two cases were considered: a highly reliable low-pressure gas system and a low-reliability one). The calculations were performed on an illustrative example of a power system. Assessment of the load supply reliability in integrated systems must factor in the process features of the systems at issue, the block diagram of their connections, as well as the accuracy of the results obtained and the complexity of searching and preparing initial data for the corresponding research model.