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The Use of Markov Chain Method to Determine Spare Transformer Number and Location
No full textThe purpose of this study is to develop a method to determine spare transformer number and location. Using Markov Chain method, state transition model and steady state probability was used on each 500-kV substation in order to analyze the effect of spare number and location variation with the reliability changes. To give an actual result of the case study, calculation of spare transformer number and location on 500/150 kV transformers in Java Bali System was analyzed. The steady state probability results will vary depending on the number of spare transformer, these results can then be used to assess the spare transformer needed. The variation of spare transformer location can be used to analyze the best possible location of the spare in order to satisfy the reliability required. The methodology presented shows an integrated calculation for determining the spare transformer number and location
Robust Multi-Objective Control of Power System Stabilizer Using Mixed H2/H∞ and µ Analysis
No full textIn order to study the dynamic stability of the system, having a precise dynamic model including the energy generation units such as generators, excitation system and turbine is necessary. The aim of this paper is to design a power stabilizer for Mashhad power plant and assess its effects on the electromechanical fluctuations. Due to lack of certainty in the system, designing an optimized robust controller is crucial. In this paper, the establishment of balance between the nominal and robust performance is done by the weight functions. In the frequencies where the uncertainty is high, in order to achieve to the robust performance of the controller, µ analysis is more profound, otherwise, in order to achieve to nominal performance, robust stability, noise reduction and decrease of controlling signal, the impact of the controller H2/H∞ is more profound. The results of the simulation studies represent the advantages and effectiveness of the suggested method
Effect of Chirality and oxide thikness on the Performance of a Ballistic CNTFET
No full textSince the discovery of 1D nano-object, they are constantly revealing significant physical properties. In this regard, carbon nanotubes (CNT) is consider as a promising candidate for application in future nanoelectronics devices like carbon nanotube field effect transistor (CNTFET). In this work, the impact of chirality and gate oxide thikness on theelectrical characteristics of a CNTFET are studied. The chiralities used are (5, 0), (10, 0), (19, 0), (26, 0), and the gate oxide thikness varied from 1 to 5 nm.This work is based on a numerical simulation program based on surface potential model.CNTFET Modeling is useful for semiconductor industries for nano scale devices manufacturing. From our results we have observed that the output current increases with chirality increasing.Wehave also highlight the importance of the gate oxide thickness on the drain current that increases when gate oxide is thin
Data Aggregation Techniques for Wireless Sensor Networks: A Survey
No full textIn Wireless Sensor Network (WSN), data from different sensor nodes is collected at aggregating node, which is typically complete via modest procedures such as averaging as inadequate computational power and energy resources. Though such collections is identified to be extremely susceptible to node compromising attacks. These approaches are extremely prone to attacks as WSN are typically lacking interfere resilient hardware. Thus, purpose of trustworthiness of data and reputation of sensor nodes is critical for wireless sensor networks. Therefore, imminent aggregator nodes will be proficient of accomplishment additional sophisticated data aggregation algorithms, so creating WSN less vulnerable, as the performance of actual low power processors affectedly increases. Iterative filtering algorithms embrace inordinate capacity for such a resolution. The way of allocated the matching weight factors to data delivered by every source, such iterative algorithms concurrently aggregate data from many sources and deliver trust valuation of these sources. Though suggestively extra robust against collusion attacks than the modest averaging techniques, are quiet vulnerable to a different sophisticated attack familiarize.At the end of this paper new technique of improved iterative filtering is proposed with the help of literature survey and drawbacks found in the literatur
Employee Performance Measurement in Teleworking Using Balanced Scorecard
No full textKey Performance Indicator (KPI) must be aligned with the development of the organization. PT. Mitra Intregrasi Informatika (MII) in its development decided to change the traditional way of work to modern telework. This encourages companies to adjust employee’s KPI from the traditional way of work turns in to telework. In order to perform KPI measurement of its employees based on teleworking, this research uses balanced scorecard method approach that is by taking into account financial, customer, internal business process and learning and growth perspective. The results of this study are the design proposal KPI employees to accommodate telework at the company. Then KPI employee test results showed an increase in the average value of the employee KPI of 0.295 points (9.47%) of the old KPI. Thus, it is recommended to the company to implement the employee KPI
The Recovery of Energy from a Hybrid System to Improve the Performance of a Photovoltaic Cell
No full textThe main objective of this work is to study a photovoltaic/thermoelectric hybrid generator system, ranging from characterisation of thermoelectric (TE) and photovoltaic (PV) modules basic elements of thermal and PV energy conversion into electrical energy through necessary modelling steps. The bibliographic study allows TE and PV generation to be positioned in the current context, by presenting their history and evolution. In some sectors, this technology has already matured. For example, in the space sector, the scientific activity seems to show an acceleration in hybrid systems development in the solar field. This research field remains completely open, as evidenced by the multiplicity of technological solutions implemented. A significant part of this work has been to develop generic energy models of various modules (PV and thermal) for a multi-source generator design, based on experimental tests and existing technologies. In addition, a methodology for sizing optimisation of such generator was proposed by considering surface or volume criteria, number of thermoelectric generator (TEG) modules and temperature gradient
Hybrid-modulation-based control technique for reduction of output voltage ripples in frequency-modulated switch-mode power converters
No full textIn this paper a novel control technique for switching-frequency-modulated switch-mode power converters (SMPC) operating in discontinuous conduction mode is proposed. The use of the technique leads to significant reduction in peak-to-peak output voltage and peak currents increased due to straightforward application of switching frequency modulation (SFM). The technique is based on hybrid modulation scheme in which both switching frequency and duty ratio are modulated simultaneously by the same modulation signal. Theoretical analysis and experimental verification of the proposed technique are presented in details. Both computer simulations and experiments show that switching-frequency-modulated SMPC with the proposed control technique in comparison to SMPC without SFM has appreaciably lower conducted electromagnetic emissions, at the cost of slightly increased peak-to-peak output voltage and peak currents
Microstrip Antenna with Photographic Paper Substrate for WLAN
No full textIn this paper a compact, flexible, Multiband antenna is designed. It is having flexible Substrate of photographic paper which makes the antenna conformal. The antenna with two U slots cut in radiating patch is offset fed by microstrip lines gives the multiple bands of WLAN /WIMAX Application and two parasitic Elements improves the bandwidth of a typical microstrip antenna. The Measured results shows that the antenna resonates between Frequency band 2.10-2.95 GHz, 3.35-3.54 GHz and 5.04-6.0Hz.which are used for application such as Bluetooth, Wi-Fi, Zigbee, ISM 2.4GHz,WLAN WiMAX, and WLAN 5.2GHz
Optimal Power Flow Solution for Wind Integrated Power in presence of VSC-HVDC Using Ant Lion Optimization
No full textThis paper studies the impact of incorporating wind power generation WPG on the power system on prsence of voltage source converter based high voltage DC (VSC-HVDC). A new meta-heuristic optimization technique are use for solving of the optimal power flow (OPF) problem, this technique optimization namely Ant Lion Optimizer (ALO). The optimization method is the Ant Lion Optimizer (ALO) method for resolve the optimal power flow (OPF) with incorporating of wind power generation on prsence of VSC-HVDC. And we used weibull distribution model of the wind farm. The ALO-OPF method has been examined and tested on standard test systems IEEE 30 bus with objective functions is minimization of cost total of production TPC are contain the sum of thermal and wind generation cost
Monitoring of PV Performance Using LabVIEW
No full textThis project aims to design a simulator for PV monitoring using LabVIEW. This project will be divided into two parts ; software where LabVIEW and Arduino IDE been contracted and hardware parts. First part involves the software development. In this project, LabVIEW program is used as the main program to monitor the output of solar panel; voltage, current, power and temperature in real time. Next, the Arduino IDE program is used to interact the sensors with the Arduino board. The Arduino Uno microcontroller board is used as data acquisition medium to collect data from the solar panel. Second, the hardware part which is PV panel setup and measurement circuit that consist of sensors and Arduino board so that the sensors data will transfer and display to the PC connected. In this simulator, the sensors are connected to the Analog I/O of Arduino Uno microcontroller which read the analogue input of sensors. The Arduino then is connected to the PC program LabVIEW to display the I-V graph and P-V graph. To make the data more significant, the data will be collected at the location 1.8635° N, 103.1089 ° E which is in Parit Raja, Batu Pahat, Johor. The data was collected with 3 different day and time; 12PM, 1PM and 2PM on 28/11/2017, 29/11/2017 and 30/11/2017