Ayodeji Ogunjuyigbe | University of Ibadan (original) (raw)

Papers by Ayodeji Ogunjuyigbe

2018 IEEE PES/IAS PowerAfrica, 2018

This paper presents an Artificial Neural Network (ANN) model to predict the excitation capacitanc... more This paper presents an Artificial Neural Network (ANN) model to predict the excitation capacitance value necessary to sustain the generated voltage of a wind-driven self-excited reluctance generator (WDSERG) within preferred limits. The network was trained, validated and tested with input data which comprises load impedances, power factor and wind speed values and a corresponding output data consisting of the excitation capacitance for each input condition. A mean square error value of less than 0.11 and an R-value of more than 0.999 were obtained for the network. These indicate a very accurate ANN training. The network was then utilized in the complete model of WDSERG under diverse input states of wind speed and load variation. The predicted capacitance value obtained from the network provides the required excitation to keep the generated phase voltage at a preferred constant level of 220±5 V under each input condition. The results depict the effectiveness of the neural network app...

The effect of changing metrological conditions on the power output performance of a local photovo... more The effect of changing metrological conditions on the power output performance of a local photovoltaic module as well as the effect of utilizing maximum power point tracking on the power output of the photovoltaic system is investigated in this paper. Firstly, the PV array is modeled using single diode, 5-parameter model and the Maximum Power Point (MPPT) control is developed and implemented in the DC-DC power converter using Perturb and Observe (P&O) intelligent algorithm. The model is then applied to a local commercially available solar panel to determine the performance and implication of utilizing MPPT on the power output of the solar panel. The results reveals that implementation of MPPT controller consistently sustained an increased power output of the PV, consequently yielding a 27% improvement in energy delivery. This paper therefore motivates for local policy on solar PV installation as it is generally observed that most PV module installed are without MPPT. ©University of ...

Engineering review, 2019

The performance of a three-phase induction motor operating under supply unbalance conditions has ... more The performance of a three-phase induction motor operating under supply unbalance conditions has been the focus of many research works using various methods. Most of the studies have focused majorly on voltage magnitude unbalance without due analysis to determine the effect of deviations in the supply phase angle from the 120° phase to phase displacement. This research investigates the significance of supply phase shift on the performance of a three-phase induction motor by applying a novel phase shift unbalance definition to the zero, negative and positive sequence components model of the motor. The test results reveal that when both phase angle shift and voltage magnitude unbalance occur simultaneously during motor operation the effect of the phase shift dominates over the effects of the voltage magnitude unbalance. This study shows that phase angle unbalance has a severe consequence on three phase motor performance.

International Journal of Ambient Energy, 2015

ABSTRACT In this paper, the wind speeds of Noupoort in the Western Cape region of South Africa ar... more ABSTRACT In this paper, the wind speeds of Noupoort in the Western Cape region of South Africa are forecasted from the site cli-matological data using feed forward artificial neural network (ANN) with the back propagation training method. Different architectural designs are tested with different combinations of climatological data to obtain the most suitable ANN for predicting the wind speed of the site. The predicted wind speeds are compared with the actual measured wind speeds and the results are evaluated using mean absolute error (MAE), mean absolute percentage error (MAPE), root mean square error (RMSE) and correlation coefficient (R). Some of the key results show that combination of temperature, wind direction and time of the day (TEM + WD + T) could effectively predict wind speed of Noupoort. The forecasted wind speed shows a strong agreement with the measured wind speed with R, RMSE, MAPE and MAE of 0.96, 0.56, 6.64% and 0.44, respectively.

Journal of Applied Science, Engineering and Technology, 2006

No Abstract. Journal of Applied Science, Engineering and Technology Vol. 4(2) 2004: 49-54

MATLAB Applications for the Practical Engineer, 2014

Renewable and Sustainable Energy Reviews, 2013

Almost all the villages consisting of more than 20 households in Iran have been grid-connected by... more Almost all the villages consisting of more than 20 households in Iran have been grid-connected by 2010 according to the Forth Five-Year Economic Development Plan (2005-2010) of the Iranian government; however, there are many isolated communities with less than 20 households that are still in need of electrification. Currently, the sole technology that provides electric power to such communities is diesel generator, which does only cause environmental problems and human health concerns, but also rank high in maintenance and operational costs. Due to the recent increasing attention of Renewable Energy Organization in Iran (acronymed as SUNA based on its Persian name) to the application of renewable energies, this paper aims to analyze the techno-economic feasibility of stand-alone hybrid PV-diesel energy systems for electrification of remote rural areas in eastern part of Iran where 5 kW h/m 2 solar radiation per day is a common feature. Through simulations based on HOMER software, this study presents a comprehensive comparative analysis among potential configurations of a system best suited to meet the needs of isolated Iranian communities.

International Journal of Sustainable Energy, 2013

ABSTRACT n this paper, critical review of various work done in the areas of wind energy resource,... more ABSTRACT n this paper, critical review of various work done in the areas of wind energy resource, modelling of wind energy conversion system (WECS) and issues regarding wind power integration into the grid are presented with the aim of examining the development, progress, achievements and direction of research. Some of the findings show that every site is unique; therefore, no generic conclusion can be drawn with regards to wind characteristics and the wind power potential of locations. The study also reveals that there is no single model of WECS. The model to be adopted will depend on the problem to be solved. This paper is useful in providing background details for wind turbine designers, researchers and practical engineers who are new in the field of wind energy

International Journal of Sustainable Energy, 2014

ABSTRACT This paper analyses the turbulence intensity of seven different sites in the coastal reg... more ABSTRACT This paper analyses the turbulence intensity of seven different sites in the coastal region of South Africa. The study is based on 12 months, 10-minute average wind speed measurement. The turbulence intensity is calculated using mean wind speed and the standard deviation method. Some of the key results show that generalised extreme value distribution gives the best fit to the turbulence intensity in the entire sites. The annual shape parameter of the distribution ranges from 0.11 at site WM06 to 0.3 at site WM05. The scale parameter varies from 3.55 at site WM04 to 6.06 at site WM02, while the location parameters span between 7.07 at site WM04 and 10.65 at site WM01. The annual turbulence intensity varies from 9.6% at site WM04 to 15.9% at site WM03. The result also reveals that sites with higher turbulence intensity have lower wind power potential and hence are less attractive for wind power application.

2019 10th International Renewable Energy Congress (IREC), 2019

In this paper, the effect of landfill gas collection efficiency as well as oxidation factor on th... more In this paper, the effect of landfill gas collection efficiency as well as oxidation factor on the electricity generation and greenhouse gas (CO2) emission is examined for a landfill gas to energy (LFGtE) technology. The study is conducted using the waste profile of the city of Ibadan, Nigeria. First, the waste generation potential of the city is determined using the population model as well as the per capita municipal solid waste (MSW) generation rate of the city obtained from the literature. The amount of landfill gas obtainable from the municipal solid waste of the city is determined using LandGem software. The result shows that the methane generation rates using LFGtE technology based on the estimated waste profile of the city is 0.2028 billion m3/yr (2315m3/h). Electricity generation potential using LFGtE technology increases with increase in collection efficiency. Conversely, it decreases with increase in oxidation factor. Also, the greenhouse gas emission potential in carbon ...

2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE), 2019

This paper investigates the impact of rewinding on the performance characteristics (i.e. energy e... more This paper investigates the impact of rewinding on the performance characteristics (i.e. energy efficiency, energy loss, steady state behavior and the harmonic distortion) of a lhp, 420V, three phase induction machine by means of laboratory experiments. First, the machine parameters are extracted experimentally and are used to simulate the steady state behavior of the machine before and after rewinding. The cost incurred due to change in efficiency of the machine after rewinding as well as the payback period if a new machine is to be purchased rather than rewinding is evaluated. The study reveals that an induction machine rewound in an average commercial rewind workshop results in small decrease in energy efficiency resulting into slight increase in energy usage. It was observed that for one to two units of induction machines, usually for domestic or personal use, rewinding might be a good option rather than buying a new one because the cost incurred due to loss of efficiency compar...

International Journal of Energy for a Clean Environment, 2021

2020 IEEE PES/IAS PowerAfrica, 2020

In this paper, a proposed grid-integrated photovoltaic (PV) system in Kankia, Katsina state of Ni... more In this paper, a proposed grid-integrated photovoltaic (PV) system in Kankia, Katsina state of Nigeria is investigated. One year meteorological data obtained from National Aeronautics and space Administration (NASA) was used for the study. The system comprises of 187,500 modules of 400Wp PV panels. Key results shows that total monthly energy deliverable to the grid ranges from 8374.4MWh to 11336MWh corresponding to the month of August and March respectively. The calculated capacity factor has a value between 15.01% and 20.32% corresppmding to the month of August and March, respectively. Performance ratio is determined to be between 71.26% in June and 76.80% in December.

Sustainable Energy Technologies and Assessments, 2016

Abstract The current–voltage relationship of the single-diode photovoltaic (PV) cell/panel equiva... more Abstract The current–voltage relationship of the single-diode photovoltaic (PV) cell/panel equivalent circuit model is defined by its implicit nonlinear transcendental equation, which is difficult to solve using analytical methods. This difficulty has led to the development of several algorithms for solving this equation using numerical techniques. This paper investigates and compares three different algorithms commonly employed in solving current–voltage equation of a 5-parameter single-diode solar PV model using manufacturer’s data sheet. The comparison is performed based on accuracy (i.e. closeness of the obtained results to experimental values), required computer memory, speed of computation, robustness of the algorithm, and ease of implementation of algorithm. The results reveal that no single algorithm performs best in all the metrics and there will always be a trade-off in the choice of the algorithms based on the user’s focus. Villalva algorithm is preferable in terms of robustness whilst T. Esram performs better in the area of computational speed, memory space and ease of implementation. No generic conclusion could be easily made in terms of accuracy as it varies with the PV technology and parameter of interest. The present work can be a potential tool for researchers and designers working in the area of photovoltaic systems, to make decisions related to the selection of the best possible algorithm for the extraction of the characteristic parameters of single-diode 5-parameter PV models.

This paper presents the influence of four operating factors (plastic type i.e feedstock, temperat... more This paper presents the influence of four operating factors (plastic type i.e feedstock, temperature, heating rate and the reaction time) on the bio-oil yield obtainable from pyrolysis of plastics wastes. To achieve this, twenty-seven (27) different experiments conducted on the pyrolysis of various plastic types under different pyrolytic operating conditions were sourced from different literature and then modelled using response surface methodology (RSM). This is to facilitate the establishment of regression relationship between the operating factors and the probable bio-oil yield from plastic waste making it possible to determine the impact of the operating factors. Some of the key results show that the regression model derived from the RSM could effectively model and predict the bio oil yield using the four operating factors with the R–square and the adjusted R–square value of 92.2% and 83.2%, respectively. It is also revealed that the different interactions among the factors resu...

Journal of Electrical Systems and Information Technology

In recent years, there have been efforts to reduce greenhouse gas (GHG) emission in order to miti... more In recent years, there have been efforts to reduce greenhouse gas (GHG) emission in order to mitigate the effects of climate change on the environment [3, 16]. There are basically two identified means of achieving this: through the reduction in energy consumption by means of energy efficiency strategy and by ultilizing renewable energy sources as part of generational mix [28]. Presently, world energy growth stands at 1.6% rate per annum, and this is expected to increase the world energy demand by 50% by 2030 [5]. As the energy demand increases, so also the GHG emission increases [11]. Most of this