Reliability evaluation of power distribution systems considering electric vehicles and distributed generation

Abstract: As human society develops, there is an increasing demand for electricity. However, the reserves of fossil fuels on earth are limited and may run out in the foreseeable future. Therefore, the possibility of replacing traditional fossil fuels with renewable energy sources is widely being investigated to resolve the world-faced energy shortage and environmental problems. The first method is to utilize more renewable energy such as wind and solar power and increase the percentage of distributed generation. Another method is to popularize electric vehicles due to their environmental-friendly and energy-saving characteristics. However, the integration of distributed generation and electric vehicles may greatly influence the operation and planning of power systems in several ways. This might result in deterioration of power system reliability. Since the society development highly depends on a safe and reliable power grid, it is essential to ensure high reliability of power systems when integrated with renewable energy resources. This master thesis aims to investigate the reliability performance of power distribution systems after integrating distributed generation and electric vehicles. First, the probabilistic model of distributed generation and electric vehicles for various scenarios are simulated. After that, a set of reliability analyses based on a standard reliability test system are carried out, in which a sequential Monte-Carlo simulation method is adopted to estimate average reliability indices. The overall conclusion is that the integration of distributed generation enhances power system reliability performance through supplying power to nearby customers in island mode. For electric vehicles, the proper regulation of charging behavior can help reduce the deterioration of power system reliability to the most extent, and the Vehicle-to-Grid mode can also improve system reliability. Furthermore, the electric bus dynamic charging mode has no additional harm to power system reliability performance than non-dynamic charging and has a promising prospect.