Advanced Materials Research Vols. 62-64

Abstract: The task of load frequency controller (LFC) is to maintain the area generation–demand balance by adjusting the outputs on regulating units in response to deviations of frequency and tie-line power exchange. In this paper, the gain of an integral controller for a two area interconnected power system is designed based on the particle swarm optimization (PSO) technique. PSO is a population based stochastic optimization technique derived from simulation of simplified social model. Simulation results on a two area network revealed that the proposed approach optimizes the parameter of integral controller by selecting the optimal gain, which dampens the frequency oscillations and change in tie-line power to zero following a step disturbance.

Abstract: In this paper, a prototype of an electronic patient record management system using smart cards is described. An application using visual basic was developed, a database using Microsoft access was built, the visual-basic-based application was then interfaced to the database. An interface module that allows any person with no programming knowledge to store easily, required information on a smart card was also developed. The application was then interfaced to a smartcard reader. With this system, relevant patient information including, but not limited to allergies, blood-group, and past operations can be retrieved from the smart card.

Abstract: Application of Pareto Analysis technique in major feeder pillar faults identification is presented in this paper. Power outage data due to feeder pillar faults were collected between January, 2005 and September, 2007 from Power Holding Company of Nigeria (PHCN), Ugbowo district office, Edo State, Nigeria for four feeder pillars. The data were processed and Pareto Analysis technique was applied to the field data. The results obtained shows that eliminating wrong fusing and overloading in Edaiken 2 and Holex feeder pillars will reduce faults by 77.42 and 79.53% respectively while eliminating wrong fusing, overloading and line-to-line faults in Uwasota 2 and Holy Rosary feeder pillars will reduce faults by 87.9 and 88.35% respectively.

Abstract: Load Frequency Controllers (LFC) are required to maintain constant power and frequency in inter-connected power generating systems. Differential Evolution (DE) based optimal tuning of load frequency controller of two area inter-connected power system is presented in this paper. The proposed method optimizes the parameter of Integral controller by selecting the optimal gain which drives the change in frequency in the two areas and change in tie-line power flow to zero within the shortest time span. Simulation results on two networks revealed that the proposed controller dampened the frequency oscillations and restores the system frequency and tie-line power to set value after a step load disturbance.

Abstract: The incidence of car theft in Nigeria has grown to nearly epidemic proportion. On daily basis, the numbers of stolen cars reported over the media are on the increase. Alarms and other deterrents are not enough. There is actually little one can do to prevent a car from being stolen. However, with a Global System for Mobile communication (GSM) activated automobile demobilizer with identification capability one can virtually take control of the virtually impossible incidence and hence increase the possibility of car recovery. This paper is aimed at implementing a security device capable of safeguarding cars from theft as well as provides picture and audio information of the culprits in an attempt to steal the car. To realize this work, use was made of a GSM phone

Abstract: In this paper, we study the performance of Binary phase shift keying (BPSK) and Quartenary phase shift keying (QPSK) modulation signalling over fast and frequency non-selective Rayleigh fading channel with mobile digital communication and usually a decision feedback equalizer (DFE) at the receiver. Mobile communication is generally a complex process in which the input modulated signals propagate to the receiver over many different paths resulting in what is known as multipath propagation. Its main effects are delay spread and Doppler spread. These effects result in the channel being classified as fast and frequency non selective. Performances in terms of Bit Error Rate (BER) with respect to the Signal-to-Noise Ratio (SNR) at different selected velocities of 10, 40, 70 and 100km/hr are investigated with Adaptive Equalizer. Simulation results are obtained using MATLAB 7.0 programming language. The results indicate that at all the velocities considered; there is an excessive degradation in the BER performance due to fading with both the BPSK and QPSK modulation schemes. However, the BER improves for BPSK modulation signalling scheme when a decision feedback equalizer is used at the receiver

Abstract: The prevalence of fire incidents in buildings resulting from electrical faults due to haphazard planning and installations have reached an alarming state in the country. Thus, this paper highlights the advantages to be derived from a properly designed and maintained electrical engineering services in buildings. The basic theory, methodology and technical considerations involved in the design and maintenance of electrical services are discussed in this paper. These were in consonance with both National and International regulations governing electrical services design and installations, such as International Electro-Technical Commission (IEC), Institute of Electrical Engineers (IEE) Regulation, Illumination Engineering Society (IES) Codes and Electrical Act of Federal Republic of Nigeria. An office apartment was used as a case study. In order to ensure safety of equipment and consumers, relevant tests to be carried out in the installation were also prescribed in this paper. Lack of proper design, poor maintenance, sub-standard materials such as cables, luminaries, electrical panels, switches and sockets, in-appropriately sized protective devices, unqualified personnel, up-patriotic attitude and wrong ultilization of electric power were identified as major factors responsible for electric faults in buildings. The paper therefore proffer recommendations to the rampant electrical faults resulting in fire incidents in both private and public buildings and the need to inculcate maintenance culture in their operations to minimise deterioration of electrical installations in buildings.

Abstract: A study of the growth dynamics of the installed capacity of the Nigerian Power System from 1963 to date was done. Perspective available generating capacity was estimated based on service life of existing installed capacity. The sufficiency of generating capacity for future normal operating modes of the system was estimated based on a power load growth forecast from 2003 to 2020. An analysis of the results shows that all the installed capacity since 1963 to the late 80s would have expired by 2020 i.e outlived their rated service lives. At present, only about 4.9 GW (80%) of total installed capacity is valid. Considering the national goal of significant economic development and estimated load forecast of over 8 GW by 2020, there is an urgent need to renovate or replace expired generating units besides the planned building of new power stations which have long gestation periods.

Abstract: This paper presented the qualitative assessment of transformer insulating oil. The breakdown voltage, dielectric and acidity tests were electrically and chemically carried out on sixteen samples of transformer insulating oil collected from various serving distribution transformers in Ilorin Metropolis in Nigeria, through the supply authority. The adequacy of the obtained results was determined by comparing experimental values with America Society for Testing and British Standard (BTA4705) pre-requisites. About seventy five percent (75%) of the tested samples failed at least one of the tests, indicating inadequacy in the routine checks. Economic impacts of the obtained results and major causes and prevention of insulation oil degradation were also presented.

Abstract: This paper presents the use of a user-interactive MATLAB programme for the design and the parameter estimation of a three-phase induction motor (TPIM) using a per phase equivalent circuit model. Optimum design parameters such as the bore diameter, the rotor diameter, the slot dimensions, the air-gap length and the performance curves are obtained by iterative procedure of a design algorithm. The performance curves of the TPIM i.e., torque and efficiency are drawn from the model’s per phase parameters and then analyzed for different number of poles, number of slots ,varying air-gap, rated slip etc and their effect on the performance of the TPIM are analyzed and the results discussed. The results obtained were validated with similar studies carried out using finite element software FEMM. The comparison shows that the TPIM model is satisfactory.