Due to the transition of traditional power system to smart structure, integration of renewable energy sources is of great importance. It is performed by using distributed generators and Micro grid. Integration of renewable sources is very useful for the reliability enhancement of distribution system as energy can be supplied locally at distributed level. Therefore, this chapter provides an overview of various reliability methods which are utilized for finding the impact of renewable energy generation on distribution system reliability assessment. These renewable energy sources are integrated in the distribution system at distributed and Micro grid level. Various characteristics of renewable energy sources are discussed to model them. A general problem of reliability assessment in terms of reliability indices is also discussed.
TopIntroduction
The primary purpose of electrical energy system is to provide reliable and quality energy to its consumers within permissible limits (Adegboye and Ekundayo, 2011). Probability of the power system to operate adequately without any outage in specified time duration under the normal operating constraints is called Reliability of the power system (Kifle et al. 2018). The performance of distribution system can be assessed with the help of available data of distribution system. Mal-functional elements of the system can also be identified with the help of reliability assessment study of distribution system. Further, elements, which require emergency replacement, can be replaced from the system. Moreover, reliability assessment study is also helpful to recommend new components in the system, so that the overall reliability of the system will enhance (Muhaini et al. 2010). Reliability methods have technical as well as economical characteristics. Therefore, for designing and operation of power system at all the stages, these techniques have been adopted as benchmark standards (Billinton and Allan, 1996). There is the transition of conventional distribution system into the smart distribution system with the integration of renewable energy sources and smart sensors (Adefarati and Bansal, 2016, Shah et al. 2015). It supports smart technologies and distributed generation units in the electrical power system, which enhances the reliability of power system by reducing the outage duration and minimizing the interruption cost. In smart grid structure, micro grid technology provides the holistic approach for the integration of renewable energy sources. It has several benefits over conventional grid system as it’s minimise energy losses, improve reliability and enhance energy management. Further, at distribution level, micro grid technology provides better solution of energy scarcity, generation coordination and control problems due to its better performance with respect to distributed generation technology (Kifle et al. 2018, Jariso et al. 2017). Further fast restoration and enhanced capacity utilization of distribution system raise the income of the utilities. By analysing the technical, environmental and economic aspects of renewable energy sources integration, reliability of distribution system can be enhanced by the power utilities. Based on the energy output, renewable distributed generation units can be integrated into the conventional distribution system. Output of these units depends on the solar irradiance of selected area, wind speed availability, repair rate, network configuration, customer load profile, etc. By utilizing the historical meteorological data of wind speed and solar irradiance of selected site, performance of wind turbine and photovoltaic panels can be easily assessed. Therefore, the availability of renewable energy sources on hourly basis can be simply predicted. Therefore, this chapter explores the integration of renewable energy sources in the form of Micro grid, for enhancing the reliability of distribution system by reducing the power outage cost (Alhelou et al., 2019; Makdisie et al., 2018; Alhelou et al., 2018; Alhelou et al., 2016; Haes Alhelou et al., 2019; Njenda et al., 2018).