Failure of power system components cause undue interruptions to Power Supply thereby affecting the Overall System reliability. Consequently, Power system reliability assessment is important for high-quality and continuous power delivery to consumers. This chapter presents the reliability assessment of Mofor Injection Substation. The performance evaluation of Mofor Injection Substation is evaluated using various system parameters which regulate the operation of the Substation. Statistical data from January, 2017 to December, 2017 were used to analyze the Substation. The results gave a power availability index (ASAI) of 0.7683796 and 0.768968 for Ekete and Orhuworun substation, respectively, due to the unavailability of strategically placed distributed generators (DGs). The aforementioned reliability result revealed that the power distribution at Mofor Injection Substation can be said to be unreliable, inefficient, undesirable, and Unstable.
TopIntroduction
A viable power system engenders economical, technological, social advancement of a nation (Kehinde & Jubril, 2013; Obi et al., 2013; Mwale & Davidson, 2014; Oluwafemi et al., 2019). Reliability assessments are therefore imperative in order to keep track of power systems performances, to aid distribution system’s planning, and to ensure the continuous availability of high-quality power to the consumers. Furthermore, reliability assessment of distribution system is sacrosanct as statistics indicate that distribution system are most prone to power interruptions (Ayamolowo et al., 2017).
Nigeria has undergone several power reforms aimed at ameliorating the power system network, while improving the overall system’s availability and reliability (Ayamolowo et al.,2019; Ayamolowo et al.,2019). However, the nation’s power generation capacity still undulates between 3795MW and 7000 MW, consequently characterized by frequent power system interruptions (Okoro et al., 2007).
In literature, assessment of power system reliability can be achieved using simulation and analytical method. The Monte Carlo simulations (MCS) technique is an example of the simulation method which comprises of standard equations used for power system reliability analyses. However, this approach is often limited by computer storage, solution time requirements and approximated solution when analyzing complex network. The direct analytical method uses reliability indices such as SAIDI, CAIDI to analyze the stochastic behavior of power systems (Georgilakis et al., 2012; Sabpayakom & Sirisumrannukul, 2016; Adefarati & Bansal, 2017; Kumar et al., 2017; Rexhepi et al., 2017).
This paper deals with the reliability assessment of Mofor distribution power system using statistical data obtained from the substation from January 2017 to December 2017. The obtained results were also validated using the MCS and it further reveals the need for strategically placed distributed generator (DG) as a means of ameliorating and improving the Power System availability of Mofor Injection Substation.
Reliability Overview and Evaluation in POWER System
Reliability assessment relates to the length of time end users are without power which is generally influenced by number of power system interruptions (Bertling, 2002; Kehinde & Jubril, 2013). Distribution circuit connects with end users using feeders through distribution transformers laterally distributed. On the other hand, a radially distributed power system is a linear interconnection of system’s components which makes distribution system susceptible to frequent power outages. Figure 1 shows the diagram of a simple radial distribution network in which a single incoming power supply is received and distributed to the utility.
Figure 1. Simple radial distribution system
Reliability Assessment Indices
In this session, we will consider the commonly used Reliability for evaluating power system performance in distribution system as defined by (Sabpayakom & Sirisumrannukul, 2016).