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Papers by ignatius okakwu

IOSR Journal of Electrical and Electronics Engineering, Jun 1, 2017

2019 IEEE PES/IAS PowerAfrica, Aug 1, 2019

This research work is aimed at performing the load flow analysis of Kaduna 132/33 kV transmission... more This research work is aimed at performing the load flow analysis of Kaduna 132/33 kV transmission station in order to ascertain its steady state operating condition. Electrical Transient Analyzer Program (ETAP) software (version 12.6) was employed in the modeling and performing of the load flow analysis using the single line diagram (SLD) and the actual data obtained from the station. The losses in the network were compensated using the Optimal Capacitor Placement OCP module on the ETAP environment. The OCP optimally sized and placed capacitors on the affected buses which improved the bus voltages of the entire network. The results obtained recorded voltage violations at Abakpa, Water works, NAF base, Rigasa, Airport, Kinkinau, Angwa Dosa and Turuku buses with magnitudes of 93.483%, 92.188%, 94.716%, 93.012%, 91.789%, 90.244%, 94.171%, 91.676% respectively. An overall system loss of 753.2 kW and 10437.3 kVAR was recorded by the network. The results from the OCP revealed that it optimally sized and placed eight capacitor banks on eight of the candidate buses which include Abakpa Bus, Water works Bus, NAF Base Bus, Rigasa Bus, Airport Bus, Kinkinau Bus, Angwa Dosa Bus, and Turuku Bus. Consequently, an improvement of 3.408%, 6.721%, 2.401%, 3.835%, 6.397%, 8.866%, 3.359% and 6.591% respectively were recorded for the buses which raised their voltage profile to 96.891%, 98.186%, 97.53%, 96.703%, 99.11%, 97.117%, 96.847%, 98.267% and 98.909% respectively. The losses were also reduced from 753.2 kW and 10437.3 kVAR to 586.1 kW and 8015.7 kVAR respectively.

Scientia Africana, Jan 29, 2023

Innovative Systems Design and Engineering, 2015

This paper addresses the dynamic behaviour of 3-? induction machines based on a quality mathemati... more This paper addresses the dynamic behaviour of 3-? induction machines based on a quality mathematical model and computer program simulation in a stationary reference frame to avoid the complexity involved in the course of solving time-varying differential equations obtained from the dynamic model. Laplace transform of the dynamic equations was carried out to derive analytical solutions the current variables. 4 th 0rder Runge-Kutta method is adopted to give numerical solution of the dynamic model. The basic electrical characteristics of the 3-? induction machine are considered in the two-phase approximate equivalent model. The graphical curves were obtained from MATLAB program code developed. Keywords: 3-? Induction Machines, Dynamic Model, Reference Frame, ??-Coordinate, Analytical and Numerical Solution, MATLAB program code

FIRAT UNIVERSITY JOURNAL OF EXPERIMENTAL AND COMPUTATIONAL ENGINEERING

Mehran University Research Journal of Engineering and Technology

This paper presents a techno-economic application of a directly-coupled PV-pumping system for dom... more This paper presents a techno-economic application of a directly-coupled PV-pumping system for domestic application in some selected rural communities in Nigeria. Four different rural communities were considered in Ogun State, Nigeria and data of volume of water requirement per household per day were obtained through the use of interview scheduled for the rural households. The system is properly sized such that the pump energy requirement is in tandem with the PV-system of the location. Six different submersible pumps of different ratings were considered for this study. The number of PV-arrays, controllers and the tank storage capacities for various pumps were also determined. MATLAB tool is used to simulate the system. The economic assessment of the system, which includes life cycle cost, energy cost of pumps and the cubic meter cost of water were also determined. The result reveals that the life cycle cost ranges from unit cost of energy ranges from unit cost of water per cubic met...

IIUM Engineering Journal

The wind speed of a location is a critical parameter for analyzing wind energy conversion systems... more The wind speed of a location is a critical parameter for analyzing wind energy conversion systems. Background knowledge has revealed that the two-parameter Weibull distribution is commonly used for fitting wind speed data because of its simplicity, flexibility and suitability. This research study examines wind speed data from five locations in Nigeria (Kano, Maiduguri, Jos, Abuja and Akure). It employs five numerical techniques, namely the maximum likelihood method, method of moment, power density method, empirical method and the logarithmic moment method, to estimate the Weibull parameters based on the locations’ data. The goodness of fit test is used to determine which numerical method best fits the distribution. The paper also considers the techno-economic design of wind electricity of five 25 kW pitch-controlled wind turbines with dissimilar characteristics. The test result presents the method of moment and empirical method as the best methods for calculating the Weibull paramet...

Advances in Intelligent Systems and Computing

Due to the ever increasing number of devices connected to the Internet, several methods, protocol... more Due to the ever increasing number of devices connected to the Internet, several methods, protocols and strategies have been developed to accommodate the increasing traffic. One of these methods is the supposed transition between Internet Protocol version 4 (IPv4) and Internet Protocol version 6 (IPv6) thereby extending the addressing capabilities of the protocols. In this study, the two addressing schemes are compared. Simulation results showed that IPv6 has better performance with respect to selected protocols such as Hyper Text Transfer Protocol, File Transfer Protocol and Jitter in Voice over Internet Protocol (VoIP) calls. Both IPv4 and IPv6 had a mean object score of 3.2, a metric for measuring the quality of VoIP calls.

Journal of Advances in Science and Engineering

The occurrence of faults in any operational power system network is inevitable, and many of the c... more The occurrence of faults in any operational power system network is inevitable, and many of the causative factors such as lightning, thunderstorm among others is usually beyond human control. Consequently, there is the need to set up models capable of prompt identification and classification of these faults for immediate action. This paper, explored the use of artificial neural network (ANN) technique to identify and classify various faults on the 11 kV distribution network of University of Lagos. The ANN is applied because it offers high speed, higher efficiency and requires less human intervention. Datasets of the case study obtained were sectioned proportionately for training, testing, and validation. The mathematical formulations for the method are presented with python used as the programming tools for the analysis. The results obtained from this study, for both the voltage and current under different scenarios of faults, are displayed in graphical forms and discussed. The resu...

Equity Journal of Science and Technology, 2020

An effective maintenance practice is one which involves a strategic framework aimed at improving ... more An effective maintenance practice is one which involves a strategic framework aimed at improving the overall performance of a system by reducing the number of failures in the system. The main attribute of sound maintenance management will be to effectively plan the system to operate with a status-quo so as to avoid all kinds of failure within the system. This paper presents a review of the present maintenance practices in the Nigeria Power System Network NPSN. It was observed from the review that the maintenance strategy presently adopted by the NPSN has not been effective due to the increase in the number of failures arising from poor maintenance. This paper proposes the incorporation of Reliability-Centered Maintenance RCM as an effective maintenance strategy in the NPSN when adopted, RCM strategy will give priority to the operating context of the equipment within the NPSN; give maintenance personnel opportunity to react to potential failures, reduce unnecessary maintenance within...

International Journal of Energy Economics and Policy, 2021

American Journal of Electrical and Electronic Engineering, 2017

The Nigerian 330kV grid network is characterized with major problems like voltage instability (vo... more The Nigerian 330kV grid network is characterized with major problems like voltage instability (voltage profile violation), long transmission lines, nature of transmission lines and high power losses which affect power generation and distribution systems. This paper considered the load-flow study of the Nigerian 330-kV consisting of 32 buses, 11 generating stations and 36 transmission lines. Newton-Raphson iteration technique was used to carry out the analysis because of its fast convergence nature as compared to other iterative techniques. The data used for the study is obtained from Power Holding Company of Nigeria (PHCN). MATLAB/SIMULINK software was used to carry out the simulations. The results obtained shows that some of the bus voltages lie outside the prescribed limit of 0.95-1.05 pu (313.5 – 346.5kV). These buses include buses 16 (Kano 0.8721pu), 17(Kaduna, 0.9046pu), 18(Jos, 0.8580pu), 19(Gombe 0.8735pu) and 21(Katampe, 0.9167pu). The total active power loss is 268.622MW an...

2020 International Conference in Mathematics, Computer Engineering and Computer Science (ICMCECS), 2020

Electrical energy enriches today’s world and so the forecast of its consumption aids energy indus... more Electrical energy enriches today’s world and so the forecast of its consumption aids energy industries, governments, as well as investors in making informed decisions at any point in time. It is on this background that this paper engaged regression analysis techniques to forecast on medium-term basis the electric power consumption within the region of Abeokuta in Ogun State of Nigeria. Three different regression techniques: linear, compound-growth and quadratic; were employed to forecast the energy demand based on previous load consumption of the study area. The performance evaluation metrics employed to measure the accuracy of the forecast are the Mean Average Percentage Error (MAPE) and the Root Mean Square Error (RMSE). Of the three techniques, linear regression recorded the least values of MAPE and RMSE. Therefore, with the employment of the linear regression technique, the load demand for July to December in 2018 was forecasted and the percentage load growth achieved for each of the months. The results obtained from this analysis could assist the management of the Regional Headquarters of the Ibadan Electricity Distribution Company on the need to make adequate planning that would facilitate efficient management of energy supply within the region.

This paper presents a comparative analysis of techno-economic viability of four different system ... more This paper presents a comparative analysis of techno-economic viability of four different system configurations (photovoltaic [PV]/diesel generator [DG], PV/battery [BAT], DG/BAT and DG-only) for energizing outdoor telecommunication sites located within the latitude 7.15˚N and longitude 3.35˚E of Abeokuta, Ogun State, Nigeria. The site used in this study has a maximum and average load of 1697 W and 39.6 kWh/day, respectively. Among all configurations examined, PV/BAT system configuration achieved the lowest life cycle cost (LCC) of ₦133,064,109 and cost of energy (COE) of ₦0.70 with a renewable fraction of 100%, adjured as the most cost-benefit configuration. However, the configuration with the least initial capital cost of ₦4,375,000 (DG-only) was the worst system configuration due to its high LCC (₦593,667,359) and COE (₦12.95). Suffice it to know that both high fuel consumption and exorbitant cost of maintenance account for this unfavorable scenario of DG-only system configuratio...

The quest to improve system voltage profile appreciably as well as to significantly reduce networ... more The quest to improve system voltage profile appreciably as well as to significantly reduce network system loss is the growing desire of power system engineers. Flexible alternating current transmission system (FACTS) devices are the emerging technologies for achieving these objectives. One of the famous members of shunt-connected FACTS controller is static synchronous compensator (STATCOM). The motivation for choice of STATCOM for critical review on Nigerian longitudinal transmission systems among other members of advanced voltage source converter (VSC) is connected to enhanced rapid usage of STATCOM in power system simulators across the globe during the last few decades. Published literatures on this concept were carefully x-rayed and presented in chronologically order. The popularity of artificial intelligence (AI) for optimal sizing and placement of STATCOM is still at abysmal level. This suggests the need for power systems researchers to switch to the use of AI techniques most e...

2020 IEEE PES/IAS PowerAfrica, 2020

Photovoltaic (PV) cells convert sunlight directly into electricity as one way of renewable energy... more Photovoltaic (PV) cells convert sunlight directly into electricity as one way of renewable energy-based power generation, a key aspect of achieving energy sustainability for sustainable economic growth. The paper as part of this goal presents an algorithm to identify various maximum power points (MPPs) on different environmental conditions of group of PV arrays. Three series connected PV arrays of similar electrical properties are considered in this paper. The conditions are grouped under three main forms; uniform test conditions (UTC), partial shading conditions 1 (PSC1) and partial shading conditions 2 (PSC2) to simulate different environmental conditions. Results obtained showed that the algorithm was able to identify all the MPPs; global or local where applicable on power-voltage (P-V) curve. For example, a global MPP of 915.7W was pinpointed on the P-V curve under standard test condition scenario type of UTC based on open circuit voltage and short circuit current of 46.3V and 8...