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Design of an automatic load monitoring and load shedding device
No full textOver time, the negative impact of overload in the distribution system network has resulted in a growing need for a more sophisticated control and monitoring system. Several methods have been limited to monitoring the electric power, power system loading level and transfer load from one feeder to another. To this end, this study focuses on designing an automatic load monitoring and load shedding device, a Supervisory Control and Data Acquisition (SCADA) device designed for utility and the University of Benin Teaching Hospital (UBTH) distribution system to prevent contingency. The method adopted is based on the load audit report carried out on the UBTH distribution network. A model is proposed, and the load audit report is used to structure the UBTH distribution network into critical and essential load demands. Each feeder is monitored, and priority is given to critical loads during load shedding. Finally, a prototype of an automatic load monitoring and load shedding device is designed and implemented with the capacity to perform the desired function. The efficiency of the proposed system is evaluated by carrying out a monitoring test, loading test, control test and converter test, which all tested satisfactorily
Fabrication of a GSM-based intruder detection system prototype based on ultrasonic sensor
No full textThe design and construction of GSM based ultrasonic intruder detection system for detecting an intruder through a protected environment was carried out and presented in this paper. An alarm is triggered when intrusion is detected through the use of ultrasonic sensor. Also, SMS is sent in the form of text to the owner’s mobile number via the GSM module being installed. The configuration and coordination required for the system units to function effectively were carried out by a programmed ATMEGA16 microcontroller. AC and DC voltage supplies were incorporated into the system to provide a constant power supply. The fabricated system was tested and found to work successfully in accordance with the target design specifications carried out as the intruder was successfully detected and SMS sent
Design and development of an electric egg incubator for industrial use
No full textAn electric egg incubator developed using locally sourced materials is presented. The study aimed to produce a low-cost electric egg incubator to enhance the production of chicks for the poultry industry. The incubator comprised a body frame, turning mechanism, egg trays, humidity control pan, fan, heat source, and controls. The design and fabrication process of the egg incubator involved an appropriate selection of engineering materials for the various parts, design analysis, and calculations of the parts, detailed machine drawing using AutoCAD, parts fabrication, and assembling of the different components. The device was evaluated using percentage fertility and hatchability with 60 poultry chicken eggs. The test results showed 81.7% fertility and 58.3% hatchability at an incubation temperature range of 36.2 to 38. The unit cost of the incubator with a capacity of 60 eggs per production was ₦105,000. This study recommends incorporating a humidity sensory device for adequate humidity control, designing for a wider incubation temperature range for other poultry egg incubation and capacity improvement, and incorporating a solar power unit for a reliable supply
Detecting defects in noncommissioned oil and gas pipelines using a ground robotic vehicle with thermal image processing
No full textLeak detection is one of the most crucial aspects of oil and gas pipeline operation. These leaks are a result of defects that may have been present before laying the pipes. Early defect detection helps a lot to save both service and maintenance costs, as well as prevent possible operational shutdowns and damages. Several methods are used for leak detection and defect identification, but most often, the approaches are usually from the external structural view of the pipes. This paper presents an internal pipe approach to defect detection through the application of a robot equipped with a thermal imaging system. The robot is developed around a Raspberry Pi B+ ARM11-based microcomputer with a Graphic Processing Unit to support a video/photographic camera. Image capture points were obtained by the location of object distance and image frame sizing. Acquired images are processed with a modified image processing algorithm using Gaussian and Sobel filters with morphological transformation in OpenCV. Results show good performance of the robot’s movement and image capture points at distances less than 80cm. Processed images also indicate areas of defects within the pipe internals
Performance analysis of a grid-connected photovoltaic/fuel cell micro-grid system in a university campus
No full textA grid-connected photovoltaic/fuel cell micro-grid optimized for university buildings is analyzed. The objective is to establish the techno-economic and environmental merits of integrating renewable power resources into an erratic electric power grid. The energy-balance method was used for the design. Case study simulations were carried out for the electric load of an information and communication technology infrastructure at Ambrose Alli University campus (latitude 6°44.0′N, longitude 6°5.1′E) using 22-year period datasets gathered from the National Aeronautics and Space Administration. The results show that hybridization of a photovoltaic generator (340kW), power converter (80kW), fuel cell system (22kW) with electrolyzer (21kW) and hydrogen tank (28kg) can sustainably augment the existing grid-diesel generator system. The potential deployment of this design on university campuses in African cities would represent great strides towards decarbonization
Development of wireless sensor nodes for data acquisition in petroleum pipelines
No full textData acquisition of parameters from oil and gas pipelines aids in the economic growth of any oil-producing nation; which in turn increases the efficiency, safety and lifespan of these pipelines significantly. This work focused on the development of the data sensors (pressure, flow and temperature sensors), Nodboxes and D-station. The Nodbox was designed using an ATmega 328p microprocessor as the control unit and an NRF 24l01+ transceiver as the wireless transmission path. Five (5) Nodboxes were designed; with one serving as the receiver at the D-station. A testbed was designed to demonstrate the reality of this system. MATLAB was used to design the GUI of the D-station to display and analyze data received graphically. Pressure, flow and temperature data were successfully transmitted from the pipeline network of the testbed to the D-station wirelessly up to a distance of 1.1km. It is cost-effective as it requires about 5 million naira to implement compared to existing systems
Implementation of an Internet-linked system for smart control of home appliances based on remote speech interaction via the Google home app
No full textSmartphones have made life easier than it has ever been because they are equipped with a lot of applications and at the same time, compact and pocketable. Several apps are available today for Internet shopping, banking, medical consulting, stock trading, and a range of other tasks. In addition to these applications, smartphones can now be employed to control our home appliances at the touch of a button or the use of voice commands. To further demonstrate the viability of this technology, a remote home control and automation system was designed and implemented. The system was based on a NodeMCU/ESP8266 Internet of Things device, Sinric Pro cloud system, and Remote Speech Interaction via Google Home App. The constructed device was tested and found to be working effectively as three light bulbs representing the home appliances, were remotely switched ON and OFF from Sinric Pro Website and also from a Smartphone via voice command on Google Home App. This device which can be mass-produced locally is hereby recommended to homes in Nigeria as this will make life easier and more comfortable
Evaluating the impact of injecting the 3050MW Mambilla power plant into the Nigerian grid network
Get PDFThe study aims to evaluate the impact of the injection of the 3050 MW Mambilla power plant into the Nigerian National Grid (NNG). To achieve this aim, line and bus data were collated from National Control Centre, Osogbo. The Mambilla power plant was injected at the Makurdi and Jalingo buses respectively in view of determining the optimal injection point. Load flow analysis employing the Newton Raphson technique was first performed without the Mambilla power plant injected into the NNG. The simulation was repeated for the respective power plant injection scenarios. For each case, the voltage profile and line losses were obtained accordingly. Total Voltage Deviations (TVDs) for the various scenarios were computed and used to determine the optimal point of injecting the Mambilla 3050MW power plant to NNG. All simulations were implemented using MATLAB software (version 2020b). A loss of 872.8 MW and 874.1 MW was observed in the network when the Mambilla power plant was injected at Makurdi and Jalingo bus respectively with respect to a base case loss of 876.1 MW. This corresponds to a reduction in a power loss of 0.36% and 0.12% respectively. A TVD of 0.0052 and 0.0169 was observed when the Mambilla power plant was injected at Makurdi and Jalingo buses respectively. This implies that the voltage condition of the network is better when Mambilla was injected at the Makurdi bus. Hence, the Makurdi bus was identified as the optimal point for injecting the Mambilla 3050 MW power plant since it resulted in a better reduction of the system losses and overall voltage profile improvement of the network
Reliability investigation of power system in Nigeria
No full textPower systems meet the demands of the consumers. However, largely unavoidable interruptions contribute to the unavailability of power supply. The sustained interruptions are the cause that greatly affects both the utility company and its customers. In this study, the investigation of power system reliability in the Ikeja Distribution Network was evaluated using the reliability indices. The analysis was done using statistical analytical methods and MATLAB software. Statistical analytical methods provide useful and higher accuracy of result since it provides high tolerance to uncertainties. The reliability data obtained from the utility substation was analysed as the outages from the utility company. The simulation indices results are shown as follows; Average Service Availability Index (ASAI) is 0.8841pu, the System Average Interruption Frequency Index (SAIFI) is 0.7239 f/customer in a year, the System Average Interruption Duration Index (SAIDI) is 3.8004 h/customer in a year, the Customer Average Interruption Duration Index (CAIDI) is 8.38 h/customer interruption in February and ASAI has as highest 0.9772 in December, SAIFI has 0.1418/customer has highest in January. While the Average Service Unavailability Index (ASUI) has an average value of 0.1159 pu/y
Emotionally intelligent chatbots-designing for empathy and emotional support: A review
No full textThe integration of emotional Intelligence into chatbots for empathy and support has brought dramatic development to many sectors. The development has led researchers to continue experimenting and studying diverse design techniques (novel and existing) to find the method(s) that best suit the building of emotionally intelligent chatbots. To address this challenge, this paper provides a reviewed literature that extracted features such as the work done, findings, limitations, and the design techniques adopted to either improve an existing model or design a new model. Findings from the reviewed papers indicate that the reviewed paper mostly used the sequence-to-sequence (seq2seq) model framework while incorporating it with other design techniques to improve on the seq2seq model. This is done based on the domain the model is built. However, other design techniques adopted by other reviewed papers are conditional variational auto-encoder, transformers, and a host of others. Although the researchers also incorporated other models with their main design technique to have a better system model