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The use of auto sanitizer in the disinfection of human body and surfaces against dangerous micro-organisms like coronavirus diseases that are infectious is of great importance to schools, family, community, and public health. The outbreak of novel Coronavirus in late 2019, which has crippled the academic, social, and economic activities globally is as a result of unhygienic activities of living creatures like, man, and animals. But a good number of technologies can be developed to tackle the emergence of this novel infectious virus. The challenge of COVID-19 that resulted to ill-health, high death rate, and shutdown of activities was being addressed radically by different medical practitioners, engineers through various practical innovations, methods and mitigation approach - ranging from the use of face shields and respiratory facemasks to practicing of social and physical distancing. This part of preventive measures has led us to developing an Auto Sanitizer that is made of Aluminum Chamber which does not wet the cloth or human body but disinfects it against COVID-19.

The performance comparison of Sliding Mode (SM) control and instantaneous reactive power theory (PQ) control for three-phase Active Power Filter (APF) is presented. Algorithms for SM and PQ techniques were developed and used in the control of APF to shunt harmonics due to non-linear loads from the power grid. Total Harmonic Distortion (THD) was used for performance verification. The PQ control reduced the THD value, on average, from 29.84% to 4.937% while the SM control reduced the THD value, on average, from 29.84% to 5.27%. The results obtained show that PQ control offered slightly better performance in terms of reduced THD than the SM control even though the implementation of SM was less complex due to the use of programmable chips. In addition, the SM control recovered faster from transient disturbances than the PQ algorithm. Both results are, however, within the conformity limit of the IEEE standard and have proven to be good for harmonic mitigation. MATLAB/Simulink 2018 version was used as the simulation tool.

Reliability and continuity of electricity supply generated by the use of fossil fuels cannot be guaranteed absolutely because of the present decline in oil and gas. Because of this, it becomes necessary to consider another form of energy generation such as biomass. In this work, the potential of electricity generation for a small household rural/isolated location using combustion technique was done. Due to the availability of sufficient biomass (agricultural waste) in rural/isolated locations, rice husk combustion technique for biopower generation was investigated in this work. The experiment was conducted at Uburu in Ohaozara Local Government Area of Ebonyi State. A 12V permanent magnet DC motor was used as the alternator while rice husk was used as biomass fuel. The biopower was achieved by heating water to steam which was used to turn the turbine attached to the permanent DC motor and a maximum of 155Whr was generated. From the result, it can be seen that the typical load of a household in a rural/isolated location is 55W and the peak experimental power is 154.96W. This peak experimental power is sufficient to carry the household load in a rural/isolated location. The peak experimental energy value is 1549.6Whr in a 10 minutes interval which is far more than the energy demand of 260Whr in a typical household in rural/isolated location. The result shows that biomass can be used to generate power for lighting point and power outlet for small households in rural/isolated locations.

A robust high-speed sliding mode control (SMC) of three phase permanent magnet synchronous motor (PMSM) is presented. The SMC served for inner speed control while a simplified hysteresis current control (HCC) scheme was used in the outer current control to generate gating signals for the inverter switches. The present research leverages on the ability of SMC to directly access system speed error which it attempts driving to zero by cancelling modelling uncertainties and disturbances. Performance comparison was done for the SMC model and an existing model having classical PI controller. With the initial positive speed command of 200 rpm at 5 Nm constant loading, rotor speed with SMC neatly settled to the reference speed at 0.085 seconds without overshoot while the rotor speed of the model with PI controller settled at 0.217 seconds after overshoot. This translates to 155.3% speed enhancement. Similar superior speed performance of the SMC was also observed during recovering from sudden speed reversal. While the SMC model recovered and settled to the reference speed of -200 rpm at 0.369 seconds, the model with PI controller settled at 0.482 seconds. From the results, it can be seen that SMC demonstared superiority over the conventioanl PI controller for complex drives systems.

An attempt was made in this work to decorated carbon nanotubes(CNTs) in a polymer matrix using biosynthesized silver nanoparticles (GAgNPs) using Cashew leaves as a reduction agent. The new hybrid epoxy-CNTs+ GAgNPs composites were produced by modified solution-stir-cast method. The microstructure, thermal properties, strength, and electrical conductivity of the produced composites were determined. The electrical conductivity of the epoxy polymer has been enhanced from 5.6x10-13S/cm to 4.80x10-3S/cm for epoxy-0.5%CNTs and 9.1x10-3S/cm epoxy-0.5%CNTs-0.5%GAgNPs. GAgNPs was effective used to improve the strength of conducting epoxy-CNTs for electronic devices. The addition of CNTs and GAgNPs to epoxy increases the glass transition temperature. It was established that GAgNPs can be promising materials to enhanced thermal conductivity, strength, electrical conductivity of epoxy-CNTs and recover the potential reduction for electronic devices application.

Nigeria is purely an agrarian nation and the people depend on agriculture for survival. One of the missing links to wealth creation in Nigeria is lack of economic exploitation of abundant agricultural wastes. Instead of wealth creation, rice husk has become a serious threat to the environment. The unutilized rice husks in rice mills in Nigeria generate millions of tons of C02 when burnt. This increases environmental degradation and deaths associated with respiratory diseases. The sustainable use of this rice husk for bioenergy applications such as electricity generation at low cost, to mitigate greenhouse gas emissions is imperative. In this paper, an off-grid gasification power supply option for Adani, in Uzo-Uwani Local Government Area of Enugu state, of eastern Nigeria is presented. A detailed load assessment and availability of rice husk for power generation in the study area was conducted. This information was used to design the gasification system. The gasification system was designed based on the mass flow rate of producer gas required to power the gas engine at full load. The gasifier was designed downdraft with air and steam as the oxidizing agent, in order to maintain uniform temperature in the oxidation and reduction zones. Furthermore, techno-economic analysis approach was used to determine the economic viability of the designed power system considered in this study. The estimated total load demand of the study area is 850.054 k W . The estimated total daily, monthly and yearly energy demands of the study area are: 8,991 ​kWh, 269,736.42 ​kWh and 3,236,837.04 ​kWh. The annual availability of rice husk in the study area is 3,636 t / y and it has potential of 1.52 M W power generation with daily, monthly and yearly energy generation of: 36.48 ​MWh, 1,094.4 ​MWh and 13,132.8 ​MWh. This potential of electricity generation has power station capacity of 1.9 MVA, which is approximately equal to 2 MVA. The Levelized Cost of Electricity of the designed power system is 3.6 Naira/kWh, which is cheaper than 30.93 Naira/kWh tariff bill by Enugu Electricity Distribution Company to its R2S customers. Based on the proposed rice husk gasification system, a community could generate power to meet their electricity demand in most economical way, thereby reducing emission, waste and saving cost translating to sustainable development.

A stand-alone roof-top solar-PV power supply is a viable and cost effective alternative to expensive and unreliable grid electricity to improve the quality of life by rural dwellers. This paper aims at highlighting the techno economic benefit of a stand-alone solar system as a viable option for production of electricity in South Eastern Nigeria. Emii is a village situated South Eastern Nigeria at Latitude 5.4511° N and longitude 7.1003° E and at an altitude of 106m. PVsyst software was used to carry out the economic analysis and it was found that the cost of energy of the stand-alone system was better than the unreliable grid supply having 0.098 $/kWh and 0.114$/kWh respectively. The Performance ration obtained from the sample was 0.653 and the solar fraction for the system is 98%. 30.802 tons of carbon emission was saved making the environment friendlier for inhabitants and payback period of 3.1years

Reliability and continuity of electricity supply generated by the use of fossil fuels cannot be guaranteed absolutely because of the present decline in oil and gas. Because of this, it becomes necessary to consider another form of energy generation such as biomass. In this work, the potential of electricity generation for a small household rural/isolated location using combustion technique was done. Due to the availability of sufficient biomass (agricultural waste) in rural/isolated locations, rice husk combustion technique for biopower generation was investigated in this work. The experiment was conducted at Uburu in Ohaozara Local Government Area of Ebonyi State. A 12V permanent magnet DC motor was used as the alternator while rice husk was used as biomass fuel. The biopower was achieved by heating water to steam which was used to turn the turbine attached to the permanent DC motor and a maximum of 155Whr was generated. From the result, it can be seen that the typical load of a household in a rural/isolated location is 55W and the peak experimental power is 154.96W. This peak experimental power is sufficient to carry the household load in a rural/isolated location. The peak experimental energy value is 1549.6Whr in a 10 minutes interval which is far more than the energy demand of 260Whr in a typical household in rural/isolated location. The result shows that biomass can be used to generate power for lighting point and power outlet for small households in rural/isolated locations

With the ever-increasing complexity of disturbed Power Systems, the method of protection using electromagnetic relays may not be adequate to afford appropriate discrimination especially when the fault current flows in parallel paths. Because the electromagnetic relay has slow response time, and the fact that it is a mechanical device and has moving parts, over a period of time, these moving parts will wear out and the relay will fail. To overcome these drawbacks, a more reliable means of system protection was carried out using solid-state contactless devices. A modular technique using five blocks made up of power supply unit, current sensor unit, voltage sensor unit, switching unit and output unit were used in the study design. A 66 kV power network was used to test the reliability of the protection designed circuit. Result shows enhanced system security.

Electricity generation in Nigeria is based on thermal and hydro generation, and is largely dominated by two sources - non-renewable thermal (natural gas and coal) and renewable water or hydro. Coal and natural gas make up the largest portion of energy production in Nigeria. The fact that a reliable power station is one which would supply the required power within its installed capacity at any time within the specified voltage and frequency limits remains vital to our economic growth, personal well-being. Essential for this evaluation are the station’s installed capacity and available generation. As the gap between supply and demand on electric energy amplifies in Nigeria, it becomes necessary to carry out the optimal reliability performance of renewable energy powered turbine generators that control the electric power industry in Nigeria. The work focuses on the past data for performance of some power stations in Nigeria from 2006 to 2017 to determine their reliability and availability of energy within their installed capacities in line with energy global best practices. The combined installed capacity of these power plant is 37% of the twenty-one thermal power plants connected to the national power grid. A historical operational data of these selected plants over a period of twelve years was obtained and evaluated based on power plant performance indices analytical techniques. The relative index of equipment reliability obtained in this study, for Afam I–V, Afam VI, Delta and Egbin are (17.13, 78.57, 34.42, & 70.17) percent accordingly. It also shows that Afam VI and Egbin power stations have good workable preventive maintenance programmes whereas, Afam I–V and Delta power stations were always faced with corrective maintenance.

This work presents ideally the behavioral characteristics of induction motor (IM) when subjected to different loading conditions. The task is achieved via mathematical modeling of the process using the Simulink tool of the Matlab. Dynamic model is generally used to study the steady state and transient behavior of induction motor. Here, Clarke and Park’s transformation of stator and rotor parameters on the synchronously rotating reference frame is applied to the developed mathematical model of the induction motor. First, the differential equations of voltages, currents and flux linkages between the stationary stator and rotating rotor are developed, followed by the mechanical equation of torque and speed. Thereafter the mathematical model developed with the help of the software is generally used to study the variation in parameters value on the dynamic performance of the induction motor as variable load is driven. The obtained simulated results apart from the exhibited performances still suggests that the synchronously rotating reference frame theory is actually a shrewd process to validate the dynamic behavior of the induction motor.

The provision of reliable electricity supply in both developed and developing nation is one of the primary needs for socio economic development of that nation. This paper turn’s to solve by way of introducing indigenous technology hybrid solar/Wind/Diesel Power system that will harness the natural renewable energies from the Sun and Wind to generate electricity. Renewable energy resources are a favourable alternative for rural energy supply. In order to handle the fluctuating nature, hybrid systems can be applied. The 2007–2016, 9 years solar radiation data, and the 2007–2016 data for wind speed for Potiskum in Yobe State of Nigeria, were collected. The two parameter Wielbull distribution was used to simulate power in watts per meter square densities for the 9 years period. Load estimates of a typical rural community and for rural ICT infrastructures were estimated. The step by step design of a 15 kW solar power supply system and a 10 kW wind power was done as a sample case. The results showed the average exploitable wind power density of 54.5 W/m2 average mean speed of 8.04 m/s. It was found that with the exception of monsoon months, August and September, solar energy can be utilized throughout the year for North-Eastern region of Nigeria. Therefore, the development of hybrid wind-solar system for off grid communities will go a long way to improve socio economy lives of people in that community.

The inability of power system to maintain a proper balance of reactive power is the major cause of voltage collapse. A system can be saved from voltage collapse by reducing the reactive power load or by adding additional reactive power into the system. The electric power system is afflicted with continuous load shedding due to inadequate generation and transmission capacities. To maximize the amount of real power that can be transferred over a network, reactive power flow must be minimized. Thus, sufficient reactive power should be provided locally in the system to keep bus voltages within stipulated ranges to satisfy customers’ equipment ratings. This paper presents an overview in reactive power compensation skills which remains as research challenges in this area. Newton-Raphson’s solution method was used to carry out the analysis because of its fast convergence, sparsity, and simplicity attributes when compared to other solution methods, with relevant data obtained from Power Holding Company of Nigeria (PHCN). MATLAB/SIMULINK was used to carry out the simulation analysis. It is observed that the application of compensation on the unified system jointly has effect on the other buses. This is confirmed by a step-by-step application of compensation at 5% intervals. The effects were noticed in Bus (20) where voltage decreased from 0.9568 to 0.9329 p.u. about 2.39%, bus (19) from 0.998 to 1.1035 p.u. and others. These results indicate undershoot and overshoot that will cause damage to the system, and may lead to system collapse if no contingency control is installed. It is also observed that compensation should be done on weak buses only for better results. The results indicate the enhancement in voltage profile in addition to reduction in the network losses and more balanced system. Active and reactive power control greatly influence the electricity grid, thus, need adequate attention with the recent advent of integration of renewable energy into the grid.

Prepaid meters have many applications in generation, transmission and distribution of electric power in Nigeria, this makes their actual power measurement to be an important issue. In this work, actual power consumption of each load was determined and was used to study the time each load will use to consume 30.8 EEDC units when it is constantly connected to power supply. The analytical method was used to investigate the collected date for different appliance consumption rate with respect to time. This experiment was conducted in Achara Layout of Enugu South Local Government Area, Enugu state. Each of the load was subjected to test to determine the current and voltages across them. The actual power consumption of each load was calculated. The time for each actual power to completely consume 30.8 units was calculated. The corresponding amount in naira per day of the actual consumption of each load was calculated. The results show that, phone and lighting points will take longer time (18421.05 and 5589.8 hours) to drain the 30.8 units; while electrical pressing iron will take 8.95hours to drain the 30.8 units. It is also seen that lighting points and phones have the least and highest consumption cost per day. By optimal combination of these loads, it will make economic sense for the subscribers of prepaid meter, and hence reduce the phobia faced by the subscribers (if not total elimination). Keywords : Actual Power, Economic Sense, Prepaid meter, Nigeria DISCOs, Tariff.