Injection Substations Research Articles

Optimal selection and design of grid-connected hybrid renewable energy system in three selected communities of Rivers State

The pursuit of electrifying rural areas has been a multi-decade quest, emblematic of Nigeria's longstanding efforts to diversify its energy sources and reduce dependence on traditional fossil fuels. Accordingly, this study aims to evaluate the electrification status and perform a techno-economic analysis of a hybrid system to ensure electricity reliability, bill reduction and reduced grid demand for three representative rural communities in Rivers State using HOMER Pro Software. Subsequently, five hybrid system scenarios that encompassed different combinations of the grid, PV modules, wind and battery, were examined using the CRITIC-PROMETHEE II methodologies. Each community was assessed based on its own hourly electricity demand, using data obtained from the injection substation. The Aluu, Choba and Rumuekini communities experienced an average daily electricity supply of 4.6, 5.4 and 6.2 h respectively from the national grid with energy usage of 5436.4 MW for Aluu, 3375.4 MW for Choba and 1626.1 MW for Rumuekini, in 2022. The findings indicate that the grid/PV module was the optimal choice for the three communities. Moreover, the cost of energy (COE) for the proposed systems ranged from 0.0181 $/kWh to 0.0185 $/kWh, significantly lower than the grid's COE of 0.08625 $/kWh in the respective communities. This research further includes a sensitivity analysis of the optimal system, examining variations in PV cost, discount rate, inflation rate, annual scaled solar irradiance and electrical demand. The results provide a comprehensive framework to support decision-making, optimize system design and align renewable energy solutions with project goals and stakeholder priorities.

Reliability Analysis of a Typical 33kV Distribution Network Using MATLAB (A Case Study of Ile-Oluji 33kV Distribution Line)

The significance of a dependable and sufficient electrical power supply in societal development cannot be overstated. The distribution of electrical power holds a crucial position in the power system chain, representing the final stage where it reaches consumers. At this phase, various types of losses, including technical loss and theft, among others are associated. The Ile-Oluji community is situated in Ondo State, a south-western part of Nigeria, A region which is host to federal, state, local and private institutions. This community grapples with inconsistent power supply experiencing intermittent trips without a clear originating cause from components in the Ile-Oluji injection substation and its feeder in Ondo. This study analyses the power distribution patterns in this locality focusing on three primary elements (transformer, switch gear and supply line) extracting data on; failures, outage time, numbers of customers and total hours for the year 2019 to 2022. Reliability indices were employed to assess its performance utilising the MATLAB software. Codes were crafted to extract these indices; Availability, Failure rates, Mean Time to Repair (MTTR), Mean Time Between failure (MTBF), System Average Interruption Duration Index (SAIDI), System Average Interruption Frequency Index (SAIFI), and Customer Average Interruption Duration Index (CAIDI). The results show that there is a strong relationship among the reliability indices. It is adduced that the lower the failure rate, the higher the availability of a system. It was concluded that the power system switchgear recorded the highest failure rate amongst the three elements with 0.037341 hrs/year followed by supply line with 0.022541 hrs/year and the transformer with 0.0148 hrs/year in 2022. In corollary, transformer has the highest availability of 0.94441 followed by supply line with 0.81681 and switchgear with 0.78004 in 2021, switchgear recorded the highest failure rates because it is responsible for executing both forced and planned outages.

Application of Power System Reliability and Outage Cost Indices on 33/11 kV Distribution Injection Substation: A Case Study of Asaba Business District

The energy satisfaction that consumers can obtain from a power service provider solely depends on how reliable the feeder to which such customers are connected guarantees adequate and secure energy delivery. This research work is, therefore, to assess the reliability indices and the cost of expected electricity not supplied to the Asaba metropolis through the Benin Electricity Distribution Company (BEDC) Asaba 33/11 kV distribution injection substation. The method used consists of computing the System Average Interruption Duration Index (SAIDI), System Average Interruption Frequency Index (SAIFI), Customer Average Interruption Duration Index (CAIDI), Average Service Availability Index (ASAI), and Expected Energy Not Supplied Index (EENS) of the four feeders emanating from the substation and radiating into the metropolis. This is achieved by first collecting the outage hour, frequency of outage, and expected energy at the point of outage from the station's hourly logbook. The input data is fed into a program written in a MATLAB/OCTAVE environment. The values of the most important reliability index, ASAI, or availability, computed on the SPC, Anwai, Express, and Asaba Commercial feeders are 0.24, 0.23, 0.23, and 0.76 p.u., respectively, in 2020, while in 2021, these values are 0.32, 0.31, 0.33, and 0.83 p.u., respectively. Using the ASAI standard value from IEEE Standard 1366-2003, which is 0.999 as a benchmark, shows that all the feeders can be categorized as less reliable in the years under study. The annual cost of expected energy not supplied during power interruptions to Asaba electricity consumers in 2020 is $2,426,187.046 and $2,214,669.91 in 2021, respectively.

Evaluating Technical Losses Arising from Power Factor Fluctuations: A Case Study of the Nekpenekpen 33/11 kV Injection Substation

Evaluating Technical Losses Arising from Power Factor Fluctuations: A Case Study of the Nekpenekpen 33/11 kV Injection Substation

Voltage profile improvement and power loss minimization of new haven injection substation for optimal placement of DG using harmony search algorithm optimization technique

Voltage profile improvement and power loss minimization of new haven injection substation for optimal placement of DG using harmony search algorithm optimization technique

Voltage profile improvement and power loss minimization of new haven injection substation for optimal placement of DG using harmony search algorithm optimization technique

The main importance of a power grid is to transfer electrical energy from the production to the consumption, while maintaining an acceptable reliability and voltage quality for all customers. The role of electrical power distributions to have centralized plants distributing electricity through Distributed Generation (DG) which reduces the Power Loss on transmission and distribution station and also improve voltage profile by optimization. This research work analyzes New Haven injection substation for optimal placement of DG generation based on wind power renewable energy source to the Distribution network and voltage stability using Harmony Search Algorithm. The model developed was simulated using MATLAB/SIMULINK software. The work applied new improved Harmony Search Algorithm for integration of renewable energy generation in the distribution network with positive impact on the operation of the voltage stability between 0.95 to 1.05p.u and reactive power distribution improvement through minimization of line losses. The total power system Loss without and with DG are 338.712KW and 307.9KW. Also, the voltage profiles of the sixteen faulty buses are stabilized for efficient performance of substation. Hence, the percentage of power system improvement is 27.23%. Therefore from the results, there is reduction of power Loss when DG is applied and optimised in the power system.

Evaluation of Electric Power Losses on 33/11 kV Distribution Feeder Networks in Uyo Urban, Nigeria Using Loss Factor Approach

No matter how carefully a power system is designed, grid inefficiencies or load losses would happen, causing power unbalance between distribution and major load centers. It is therefore fundamental to clearly determine and identify electric power system losses for network improvement because of their financial-economic value to distribution companies and consumers. In this work, relevant data including monthly loading, feeder route length, and cross-sectional area of four 11 kV feeders namely, Aka, Ibrahim Babangida, Udo Udoma, and Idongesit Nkanga secretariat-dedicated feeders were obtained from the Port Harcourt Electricity Distribution (PHED) company technical office, Uyo, Nigeria for four years (January 2018 to December 2021) for the 33/11 kV Akwa Ibom State Secretariat Injection Substation and distribution feeder circuits. Average load, maximum load, load factor, loss factor, power losses in the feeders and total power loss in the system were computed and the results which were shown graphically revealed grid inefficiencies and power imbalance or losses which increased slightly on a yearly basis. The losses are due to heat dissipation, lack of maintenance of the power system components, transformer overloading, copper losses, core losses, lengthy feeder routes, and location/aging of the transformers. Suggestions were made in order to reduce further losses in the network.

Scalable and Characterization Methods and Tools for Remote Monitoring of Off Grid Technologies: Case Study of 3x15mva Power Distribution Injection Substation in Nigeria

Remote control and monitoring of energy resources are vital for the effective management of electricity in rural areas. Access to electricity in rural areas of Nigeria has grown in recent years. Nigeria appears to be growing rapidly in the electrification of both rural and urban areas through the use of distributed energy resources using renewable energy. Nevertheless, there have been challenges in the remote monitoring of the energy resources in the rural area. The challenges include high cost of implementation, available technology, power consumption, system integration, social-Economic challenge, etc. This paper present a cost-effective concept for remote monitoring systems of distributed energy resources (off-grid/mini-grid) and on-grid/main-grid technologies based on free open-source Supervisory Control and Data Acquisition (SCADA) or vison CC software that runs on a server located at the central station and a robust interface panel where the sensors measure system parameters, which are subsequently analyzed by signal processors before being transferred to a central location, where data is stored on the server's hard drive. The remote monitoring system is for monitoring and collection of energy data such as current, voltage, power, and environmental data such as temperature and humidity. The basic remote monitoring system consists of two components: a transmitter located at a remote site (where the mini-grid is installed) and a receiver located at the central station (where the system monitoring process is done). The proposed concept comprises various means of connecting locally with the remote system, with the connection being through Universal Serial Bus (USB), RS232, RS485, or Ethernet, where this data is stored on a central relational database management system, which makes it possible for posterior analysis.

Power supply enhancement in Onitsha distribution network using distribution generations

The research explored ways in which power supplied in Onitsha distribution line network would be enhanced using distributed generation. The problem of insufficient power supply in densely populated metropolis which is characterised by frequent load shedding was solved using optimal placement and sizing of multiple distributed generation. A gas plant was optimally placed at 33 kV injection substations at Awada and General Cotton Mill (GCM). The generators were optimally placed using voltage sensitivity index factor, while their optimum capacities were sized using step method. Simulations were done by power system analysis toolbox (PSAT) 2.1.11 simulation tool in MATLAB 2018a environment and the result of the findings revealed that 32 buses out of 34 buses were violated. The result of the simulation also showed that the optimal operating power output of the generators at Awada and GCM of 12.5 MW and 2.5 MW respectively could only clear 29 out of the 32 bus voltage violations. Overloading of Fegge injection substation transformer was identified as the cause and its upgrade from 7.5 MVA to 15.0 MVA cleared all the voltage violations. The system active loss and reactive loss were 1.82 MW and 35.03 MVar and the research was able to reduce them by 23.30% and 23.80% respectively. The statutory bus voltage limits of ±5% and the requirement that distributed generators installed must be less than the maximum demanded had been achieved in the research. The power supply in Onitsha distribution network was enhanced using distribution generations and the usage of optimal placement and sizing of multiple distributed generation is therefore recommended for problematic distribution networks not only for loss reduction also for better performance.

Tripping Profile Analysis of the 33 kV Feeder of Ugbowo 2 x 15 MVA, 33/11 kV Injection Substation

This paper investigated the tripping profile of the 33 kV feeder of Ugbowo 2 x 15 MVA, 33/11 kV electric powerdistribution network. The annual data of daily tripping of the 33 kV feeder from September 2019 to August 2020were collated and collected from the Ugbowo injection substation. The daily outage of the 33 kV feeder was usedto compute the monthly and yearly tripping profile of the sub-transmission line (33 kV feeder) of the Ugbowoinjection substation. The monthly and yearly failure rate, MTTR, MTTF, MTBF, availability, unavailability, SAIFI,SAIDI, ASAI, ASUI, etc. for the period of twelve (12) months were analyzed using the Load Point Indices (LPI)and Microsoft Excel was used graphically to interpret the results of the tripping profile of the 33 kV feeder. Theresults obtained from the analyses of the 33 kV feeder of the network showed that yearly failure rate, MTTR,MTTF, MTBF, unavailability, availability, SAIFI, SAIDI, ASAI and ASUI were 4.32%, 6.520 h, 23.148 h, 29.668h, 21.98%, 78.02%, 0.0358 interruptions/customer/yr, 0.2336 h/customer/yr, 78.03%, and 21.97%, respectively.These results revealed that the performance indices of the 33 kV feeder with annual total outage frequency (SAIFI)and percentage availability (ASAI) were a far cry from the recommended values of the internationally acceptablestandard value (IASV) of 0.01 and 99.99% respectively. This poses a threat to the reliability and availability ofelectricity supply to consumers.

Reliability Evaluation of 33/11kV Olunde Injection Substation for Improved Performance

Electric power supply reliability (PSR) is crucial in the present economy to avoid huge economic loss and life discomfort. Thus, there is need to improve PSR. Reliability evaluation of power equipment was carried out on Olunde 33/11kV Injection Substation using extracted and available five years data of Fault Frequency and Downtime of associated power equipment for 2016 to 2020 from the Injection Substation’s log books. Fault Tree Analysis (FTA) Technique was used in this research. The existing Injection Power Substation results shows that the overall injection substation unavailability of power supply was 0.00672; 33kV NBL Feeder alone has the highest percentage of failure contribution 72.97% of the unavailability of the injection substation. The reliability improvement of the Injection Power Substation using doubling maintenance activities method on the NBL 33kV feeder shows that the overall injection substation unavailability improved from 1:1.57; the NBL 33kV feeder failure contribution reduced to 15.63%. Using a redundant feeder, 33kV feeder, the overall unavailability of the injection substation improved from 1:3.6; the NBL 33kV failure contribution reduced to 1.31%. The redundant feeder approach in this work is highly significant since it is better than the doubling maintenance activities method .

ENHANCEMENT OF ARC CONTROL AT BORIKIRI 11/33KV DISTRIBUTION STATION, PORT HARCOURT, RIVERS STATE

This research work has highlighted the benefits of enhancement of arc at Borikiri 33kV Distribution Network in Rivers State, Nigeria. The flash arc analysis was modelled and simulated using ETAP 12.6 software environment to show the sequence of operation of arc flash from the Injection substation to the Transmission Station. The analysis focus on the fault current occurred at some point once the relay protection device issued a clearing time in seconds, the circuit breaker was absolutely tripped and when an arc fault occurs, the latched fault occurred showing that a short circuit that has no electrical resistance at the point of the fault, that is characterised by an absence of arcing. The case study shows the connection between the clearing/tripping time and fault current for the prevailing and simulated case study; for the existing case study shows the minimum values and therefore the most values, once the clearing/tripping time was 0.011 sec, the fault current was 32.20 kA and when the clearing/tripping time was 0.025 sec, the fault current was 34.12 kA, the result show the behavior of the graph as linearity. The graph shows that as clearing/tripping time will increase, fault current increases slowly at first. Similarly, because the clearing/tripping time and the the} fault current will increase slowly at first, then additional rapidly, then slows down once more and reaches a most level. The simulated case study also shows the link between the fault current and clearing time shows the minimum values and the maximum values, once the clearing/tripping time was 0.062 sec, the fault current was 4.62 kA and when the clearing/tripping time was 0.26 sec, the fault current was 5.01 kA, the graph show that as clearing/tripping time increases, fault current increases slowly at first. Relationship between the incident energy, flash protection boundary and clearing time of the prevailing case study; once clearing or tripping time was zero.011 sec, the flash protection boundary was 1.03 feet, and therefore the incident energy of 0.73 cal/cm2 , according to standard for Electrical Safety, our result shows that Hazard Risk categories is 0 (HRC 0) that cause a second degree burn to unprotected skin.

Optimization of Energy Efficiency for Electric Power Distribution System Losses

Abstract: This study evaluated the existing electric power network of Mile 2 Diobu zone, Port Harcourt distribution network which consists of four (4) 11kV distribution feeders namely; Ojoto, Nsukka, Udi and Silverbird. This work considered Ojoto and Nsukka Street distribution network for improved power quality. The three (3) 33/11kv injection substations are fed from 165 MVA transmission station (PH Town) at Amadi junction by Nzimiro. Collection and analysis of data collected from the injection substations that supply electricity to mile 2 Diobu, Port Harcourt was the first consideration. The distribution network was modeled in Electrical Transient Analyzer Program (ETAP) using Newton-Raphson Load Flow equations. The simulation result of the existing condition network shows that the network has low voltage profile problem on Nsukka network and overloading of distribution transformers on Ojoto networks. The following optimization techniques are applied: up-gradation of distribution transformers, and transformer load tap changer to improve the distribution network for Mile 2 Diobu, Port Harcourt electrical power network. The simulation result of the improved distribution network for Mile 2 Diobu, Port Harcourt power network shows that the voltage profile Nsukka network has improved within the statutory limit which is between 95.0 -105.0% and the loading of the distribution transformers on Ojoto and Nsukka networks are all below 70% required capacity. Keywords: Optimization, Energy Efficiency Distribution

Monitoring and Evaluation of The Reliability of Distribution Network with Distributed Generation

With the growing population of Ezenei 11KV feeder radiating from the Asaba mains Injection Substation and overstretched distribution network, monitoring and evaluation of the reliability and improvement of distribution network feeder is essential. Failure of some of the equipment at supply restoration is frequent due to weakness of some of the line conductors and long usage of the equipment. In this research work, simulation, analysis and evaluation of the reliability and improvement of Ezenei 11kV feeder was investigated. Load data used were collected from Benin Electricity Distribution Company (BEDC) Asaba between February and April 2018 and this was used to model the sixty – seven (67) buses on the network using Electrical Transient and Analysis Program (ETAP). Load flow analysis was carried out on the modelled network using Newton – Raphson (N-R) iteration method to determine the various bus power (active and reactive) and voltage magnitude using the base and distributed generation injected power. Reliability study was carried out on the network and result showed that the load point indices were increasing as distance of load point increased from feeder. The Seventeen load buses which was Okeke bus to Starcom bus forms the location A. and St. Rebecca bus to Chief Ofili bus forms location B. while Odogu bus to Old Deputy Govt. bus forms location, Iyabi bus to MTN III bus forms location D. Okeke and Jimok water which are the closest load buses to the feeder have an Average Interruption Rate (f/yr) and Annual Output Interruption Rate (hr/yr) of 8.9264f/yr, 417.1507hr/yr while Victor Odogu and Auditor General has an Average Interruption Rate (f/yr) and Annual Output Interruption Rate (hr/yr) of 8.9318f/yr, 417.2857hr/yr and 8.9264 f/yr, 417.1507hr/yr. It was also observed that Chief Osita, Anacho and Estate buses had the highest Average Interruption Rate (f/yr) and Annual Output Interruption Rate (hr/yr).

Distribution Network Reliability and Efficiency Enhancement Using Distributed Generation

The Nigerian power sector is faced with many challenges such as: generation deficit, inefficiency and power loss over lengthy transmission and distribution lines, contribution to greenhouse gas emission, weak and dilapidated transmission and distribution infrastructure, dependence on fossil fuels, insufficient power. Efforts should be put in place by relevant authorities to improve the power sector. With the distribution network being the closest to the final consumer, efforts should be made to make it more efficient. This study therefore aims at improving the performance of poor distribution network using Distributed Generation (DG), optimally placed and sized in the network. The Asaba, 2 X 15MVA, 33/11kV injection substation in Asaba, Delta state of Nigeria consisting of Anwai road feeder and SPC feeder radiating outwardly from this injection substation was the focus of this study. Relevant data collected from Benin Electricity Distribution Company (BEDC) was used to carry out load flow study. The simulation and analysis of the result and injection of photovoltaic (PV) DG of Asaba injection substation distribution network using Newton-Raphson iteration technique in ETAP 12.6environment to ascertain the overall performance of the network under base loading condition was modelled from a drawn detailed single line diagram of the network. DGs were optimally placed in specific buses in the network using loss sensitivity analysis. The result revealed that prior to DG placement in the network, only 10.4% of the buses were within statutory voltage limit (394.25V – 435.75V or 0.95p.u – 1.05p.u) and 89.6% of the load buses in the network violated the statutory voltage limit and high losses (active and reactive) of 1329.08kW and 2031kVar. After the optimal placement of DG, the active and reactive power losses on the network reduced by 57.5% and 70.7%. While the voltage profile improved by 94.8%, thereby increasing the capacity, reliability and efficiency of distribution network.

Design of Effective 33/11 kV Injection Substations Using International Standards

This research focuses on the design of an effective 33/11 kV modelled injection substation that conforms to an appropriate standard for equipment protection, the safety of personnel and power quality compliance. This is to provide a solution to one of the major problems industries in Nigeria faces due to sudden voltage fluctuations in the power system which results in damages to equipment and thus outage of power supply and damages to substation equipment. The methodology involved designing an effective 33/11 kV injection substation and associated distributive substation elements using international codes and applicable algorithms. 60% loading of transformer and additional 1.25 factor of future expansion (F.E) were considered too. The results showed that a 7.5 MVA injection transformer was designed to operate at 60%. Also, the results revealed that the injection substation would feed 15 numbers of 500 kVA distributive transformers. Each distribution substation was sized in accordance with the 7.5MVA injection transformer philosophy in this work. This research concludes that the injection substation must be loaded at 60% with an additional 1.25 F.E. in order to increase the transformer life span, and the 7.5MVA injection substation can crater for 15nos of 500 kVA distribution transformers in this research. Each substation will reliably and effectively carry the expected load demand. This research recommends that injection substations should be designed for areas with high energy requirements for reliable power quality. It recommends that substations should conform to 60% loading at the initial years of usage and that the substation design should conform to appropriate standards used in this work.

Power quality considerations for embedded generation integration in Nigeria: A case study of ogba 33 kV injection substation

The deregulation of the Nigerian power sector has resulted in the quest to explore power generation options for power quality improvement. One of such options is the pattern shift from central power generation to embedded power generation. Network integration of embedded generators (EGs) causes several regulatory, technical and economic issues. This research focuses on power quality challenges that may arise as a result of network integration of embedded generation in a weak electricity networks using Ogba 33 kV injection substation as case study. The embedded generators considered comprised of gas turbine and diesel generators. NEPLAN software was used to perform the load flow analysis with and without EGs connection on the network. This was necessary so as to ascertain the healthiness of the existing distribution network for EGs integration. The power quality issues considered in the study were bus voltage profiles and the total line losses. Simulation results showed that EGs connection improved the voltage profile, for example, bus voltage at PTC 11 kV, improved from 0.881 pu to 0.958 pu while the total active power loss was reduced by 78.16%. The results obtained suggest that the grid is healthy enough to accommodate the EGs with no quality issues.

Comparative Analysis of Fuzzy Inference System (FIS) And Adaptive Neuro-Fuzzy Inference System (ANFIS) Methods in the Classification and Location of High Impedance Faults on Distribution System

Unlike low impedance faults, which involve relatively large magnitude of fault currents and are easily detected by conventional over-current protection devices, high impedance faults pose a serious challenge to protection engineers because they can remain on the system without the protective relays being able to detect them. This paper presents an improved method for detection and location of high impedance fault using ANFIS model. The study was conducted on the 33 kV Uyo-Ikot Ekpene power distribution line. The case study power distribution system was modeled using MATLAB software. HIFs were introduced at various locations along the distribution line. The data obtained from the MATLAB/Simulink simulated fault using discrete wavelet transform (DWT) were used to train the ANFIS for the location of HIF points along the distribution system as well as for prediction of the distance of the fault location to the nearest injection substation. The results show that ANFIS model gives 52.5 percentage reduction in error compared with FIS in the location of fault points on the case study power distribution system.

Comparative Analysis of Fuzzy Inference System (FIS) And Adaptive Neuro-Fuzzy Inference System (ANFIS) Methods in the Classification and Location of High Impedance Faults on Distribution System

Unlike low impedance faults, which involve relatively large magnitude of fault currents and are easily detected by conventional over-current protection devices, high impedance faults pose a serious challenge to protection engineers because they can remain on the system without the protective relays being able to detect them. This paper presents an improved method for detection and location of high impedance fault using ANFIS model. The study was conducted on the 33 kV Uyo-Ikot Ekpene power distribution line. The case study power distribution system was modeled using MATLAB software. HIFs were introduced at various locations along the distribution line. The data obtained from the MATLAB/Simulink simulated fault using discrete wavelet transform (DWT) were used to train the ANFIS for the location of HIF points along the distribution system as well as for prediction of the distance of the fault location to the nearest injection substation. The results show that ANFIS model gives 52.5 percentage reduction in error compared with FIS in the location of fault points on the case study power distribution system.

ELECTRICAL LOAD RELIABILITY ASSESSMENT USING ANALYTICAL METHOD, CASE STUDY: FUPRE 1 X 2.5MVA INJECTION SUBSTATION

This research work presents the reliability assessment of electrical load distribution system in Federal University of Petroleum Resources, Effurun (FUPRE), Warri using the Analytical method and ETAP software as the simulation tool to run the reliability assessment of the System. The analytical analysis was conceded out by using August 2018 – August 2019 historical data of Tetfund Classrooms Blocks, Hostels, College of Technology, Administration Block, Health Center, and College of Science Feeder obtained from the Benin Electricity Distribution Company [BEDC]. The results conceded revealed that College of Technology Injection Substation is the most reliable in the distribution network when compared to the other five substations around the institution premises as it recorded system indices of ASAI: 99.30, SAIFI: 1.10, SAIDI: 55.35, CAIDI: 123.04 in August 2018 to August 2019. Nevertheless, the total reliability indices of the six substations under investigation as obtained from the analysis, and it shows that availability of power to FUPRE distribution is very poor as compared with the benchmark of IEEE ASAI of 99.99 for distribution substation availability.