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Hybrid Renewable Energy Systems for Electrification: A Review
Ibrahim Baba Kyari,
Jamilu Ya’u Muhammad
Issue:
Volume 8, Issue 2, December 2019
Pages:
32-39
Received:
8 July 2019
Accepted:
27 July 2019
Published:
14 August 2019
Abstract: Renewable energy systems are becoming widespread in the future due to adverse environmental friendly and abundant in nature. Solar and wind energy resources are alternative to each other which will have the actual potential to satisfy the energy demand. But wind energy system may not be technically viable at all sites because of low wind speeds and being more unpredictable than solar energy. Due to this reason a combined utilization of these renewable energy sources are therefore becoming increasingly attractive and are being widely used as alternative of oil-produced energy and this is called “Hybrid Renewable Energy Systems. These hybrid energy systems are becoming popular in remote area power generation applications due to advancements in renewable energy technologies and substantial rise in prices of fossil fuel. This paper presents an extensive review on hybrid renewable energy systems configurations, mathematical modeling and control strategies of the system. This Paper also highlights the optimization techniques which have the potential to increase the economic attractiveness of the system.
Abstract: Renewable energy systems are becoming widespread in the future due to adverse environmental friendly and abundant in nature. Solar and wind energy resources are alternative to each other which will have the actual potential to satisfy the energy demand. But wind energy system may not be technically viable at all sites because of low wind speeds and...
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Satellite Image Used to Solve the Impact of Silt and Velocity on Discharge Carrying Capacity of Right Bank Canals of SukkurBarrage Pakistan
Farhan Hussain Wagan,
Sadaf She,
Ghulam Hussain Wagan
Issue:
Volume 8, Issue 2, December 2019
Pages:
40-46
Received:
21 June 2019
Accepted:
3 August 2019
Published:
15 August 2019
Abstract: Pakistan is basically an agricultural country, agriculture is considered the back bone of the country. It helps country in earning foreign exchange, about 90% of output comes from agriculture, supports in employment and economy by exporting food grains. Luckly Pakistan has worlds third giant irrigation system, it comprises best storage infra-structure, controlling system of barrages, regulators, conveyance system of canals and an efficient drainage system both horizontal and vertical. Indus river basin irrigation system has three major reservoirs, sixteen barrages, two head works, two siphons across major rivers, 12 inter river link canals and 44 irrigation canals. Average gradient was observed from sea level as flat with rate of 12.5 cm/km (eight inches/mile), Indus provides irrigation system to major portion of Sindh almost 41 percent. The total Gross Commanded area of Sindh and Baluchistan which depends on Indus is 5.92 Mha whereas, the only Cultivable command Area is 5.43 Mha. The major crops grown in Sindh are rice in Kharif and wheat in Rabi. Besides this, Sindh also produces horticultural crops such as: mangoes, bananas, dates and chilies. Sindh has also diversion capacity of 111 billion cubic meter (BCM) which is equivalent to 90 million Acre Feet (MAF). It was found in the research that excess of silt in Right Bank Canal is more to reduce the velocity of water. Satellite image based model shows negligible velocity to Right Pocket at Sukkur Barrage. 60% less cultivation in 2018 at SaifullahMagsi Branch Division at border of Sindh-Balochistan.
Abstract: Pakistan is basically an agricultural country, agriculture is considered the back bone of the country. It helps country in earning foreign exchange, about 90% of output comes from agriculture, supports in employment and economy by exporting food grains. Luckly Pakistan has worlds third giant irrigation system, it comprises best storage infra-struct...
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Floyd’s Modified Computational Method Applied to Calculate Step Response of a Regilator from Frequency Response
Jose Flavio Feiteira,
Jose Luiz Guarino,
Rodrigo Guerra de Souza
Issue:
Volume 8, Issue 2, December 2019
Pages:
47-52
Received:
10 July 2019
Accepted:
12 August 2019
Published:
23 August 2019
Abstract: This work explains how to obtain the unit step time domain response by means of the frequency response of a regulator (gain and phase) using the Floyd’s Modified Computational Method. The preliminary condition is that the gain of the system tends to zero as the frequency tends to infinite. Floyd’s Method uses the Fourier’s Inverse Transform to achieve the Impulse Unit response. The Modified Method calculates the integral. This work details the mathematical developnent of Floyd’s Method. Authors introduce the integral of the Impulse Unit response to obtain the Step Unit response and also the linearization of the Method in order to approximate it and obtain an equation to do the computational calculation. We apply the modified method in a second order system, calculating its frequency response and its analytic step unit response by means of the MNatlab. Then we use the equation developed in this work by the linearization of Floyd‘s Modified Method applied in the frequency response of the system and compare with the step unit analytic response. The relative error is calculated and we can observe that Floyd’s Modified Method generates a step unit response in the time domain that has some time little retard and with values a little inferior to the analytic response. This behavior is attributed to the linearization and to do not use the complete frequency band of the system. However the final values are very exact. T.
Abstract: This work explains how to obtain the unit step time domain response by means of the frequency response of a regulator (gain and phase) using the Floyd’s Modified Computational Method. The preliminary condition is that the gain of the system tends to zero as the frequency tends to infinite. Floyd’s Method uses the Fourier’s Inverse Transform to achi...
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Analysis of the Power Blackout in the Ethiopian Electric Power Grid
Moges Alemu Tikuneh,
Getachew Biru Worku
Issue:
Volume 8, Issue 2, December 2019
Pages:
53-65
Received:
5 July 2019
Accepted:
31 July 2019
Published:
26 August 2019
Abstract: In recent years, with an increasing load demand for rural electrification and industrialization, the Ethiopian power system has faced more frequent, widely spread and long-lasting blackouts. To identify the impacts, analyzing and studying the reasons and the mechanisms of such blackouts would be the first step and so, the January 6th, 2016 blackout of the Ethiopian Electric Power (EEP) is reviewed based on the data that are available at the National Load Dispatch Center (NLDC) archive. The analysis is done by considering the sequential phases of the blackout: system condition prior to the power failure, initiating events, cascading events, the final state of the power system and its restoration. Computer simulations are then performed using DIgSILENT PowerFactory software to identify the root cause of the blackout and evaluate the initiating event that had triggered the sequence of events that followed. In doing so, two procedures are followed. Firstly, power flow simulation is run to analyze the system performance under steady state conditions to determine the voltage magnitude at critical buses and the loadings of lines and generators prior to the disturbance. Secondly, time domain simulations are performed to analyze the system performance under transient conditions for the specified initiating and cascading events. Above all the possible method is suggested for the prevention of such incidents.
Abstract: In recent years, with an increasing load demand for rural electrification and industrialization, the Ethiopian power system has faced more frequent, widely spread and long-lasting blackouts. To identify the impacts, analyzing and studying the reasons and the mechanisms of such blackouts would be the first step and so, the January 6th, 2016 blackout...
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Dynamics of an Optically Injected Diode Laser Subject to Periodic Perturbation: Occurrence of a Large Number of Attractors, Bistability and Metastable Chaos
Thiery Tchinda,
Zeric Njitacke,
Theophile Fozin Fonzin,
Hilaire Fotsin
Issue:
Volume 8, Issue 2, December 2019
Pages:
66-75
Received:
14 November 2019
Accepted:
11 December 2019
Published:
25 December 2019
Abstract: It is well known that during a certain interval of time, a molecule of gas in the beam path from the pump laser (master) to the injected laser (slave) can decrease the power injected [1]. In this contribution, we consider a well-known rate equation model of semiconductor laser to explore numerically the effect of a periodic perturbation from the pump laser (master) on the dynamical behavior of the injected laser (slave). Using nonlinear diagnostic tools such bifurcation diagrams, graph of maximum Lyapunov exponent, phase portraits, Poincare sections, basin of attraction and two parameter diagrams, the dynamical behavior of the model is analyzed in terms of its parameters. The coexistence of periodic and chaotic attractors as well as the occurrence of ten different attractors (symmetric and asymmetric) and transient chaos are demonstrated. Finally, PSpice simulations are performed to support numerical results.
Abstract: It is well known that during a certain interval of time, a molecule of gas in the beam path from the pump laser (master) to the injected laser (slave) can decrease the power injected [1]. In this contribution, we consider a well-known rate equation model of semiconductor laser to explore numerically the effect of a periodic perturbation from the pu...
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Performance Improvement of 4-Bit Static CMOS Carry Look-Ahead Adder Using Modified Circuits for Carry Propagate and Generate Terms
Mehedi Hasan,
Moumita Sadia Islam,
Muhtasim Rafid Ahmed
Issue:
Volume 8, Issue 2, December 2019
Pages:
76-81
Received:
2 December 2019
Accepted:
18 December 2019
Published:
27 December 2019
Abstract: Carry Look-Ahead Adder (CLA) is considered as one of the most widely used adder topologies which are used in high performance computing systems. In this research, an improved version of 4-bit CLA adder has been proposed. Performance improvement of 4-bit CLA adder has been made by using hybrid AND and XOR gates in the input side for generating carry propagate and carry generate terms. The CLA circuits are kept exactly the same as the conventional one. Performance of the proposed modified 4-bit CLA adder has been evaluated and compared with the conventional design using Cadence tools in 90 nm technology node. Performance has been evaluated and compared in terms of average power, propagation delay and power delay product. The proposed modified design exhibited significant improvement in performance while compared with the conventional one. Enhancement done by the proposed 4-bit CLA adder design in average power, propagation delay and PDP were 14.96%, 11.76% and 25.32% respectively. In addition to performance enhancement, transistor count require for the proposed design is quite less compared to the conventional design which result in less surface area on chip. Moreover, less transistor count accounts for less power dissipation. Hence, utilizing the proposed design in modern high-performance computing systems would bring about high-performance improvements.
Abstract: Carry Look-Ahead Adder (CLA) is considered as one of the most widely used adder topologies which are used in high performance computing systems. In this research, an improved version of 4-bit CLA adder has been proposed. Performance improvement of 4-bit CLA adder has been made by using hybrid AND and XOR gates in the input side for generating carry...
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