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Low Power Parallel Prefix Adder Design Using Two Phase Adiabatic Logic
Alireza Hassanzadeh,
Ahmad Shabani
Issue:
Volume 3, Issue 6, December 2015
Pages:
181-186
Received:
24 October 2015
Accepted:
6 November 2015
Published:
7 December 2015
Abstract: In this paper low power implementation of parallel prefix adders using two phase adiabatic logic has been investigated. A new structure has been proposed for the main blocks of parallel prefix adder. Three parallel prefix adders including Kogge-Stone, Brent-Kung and Ripple Carry have been considered. The effects of power clock frequency and loading capacitance on the new blocks have also been considered. Simulation results using 180nm technology parameters and trapezoidal waveform show an average of 34% power reduction in the main building blocks of the adder at 200MHz clock frequency. This power reduces to 54% for sine wave power clock waveform. This research suggests adiabatic implementation of parallel prefix adders for low power microprocessor and signal processing applications.
Abstract: In this paper low power implementation of parallel prefix adders using two phase adiabatic logic has been investigated. A new structure has been proposed for the main blocks of parallel prefix adder. Three parallel prefix adders including Kogge-Stone, Brent-Kung and Ripple Carry have been considered. The effects of power clock frequency and loading...
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Evaluation of Resistance Type SFCL on Reduction of Destructive Effects of Voltage Sag on Synchronous Machine Stability
Behrouz Alfi,
Tohid Banki,
Faramarz Faghihi
Issue:
Volume 3, Issue 6, December 2015
Pages:
187-191
Received:
3 November 2015
Accepted:
13 November 2015
Published:
7 December 2015
Abstract: Electrical power quality has become an essential part of power systems and electrical machines. True identifying and regarding power quality and how to check the related destructive points are of utmost importance. Most of the time, providing the quality of power for sensitive load which requires the voltage to maintain a sinusoidal waveform at rated voltage and frequency is the main point to be considered. On the other hand, protecting power supply against resulting turbulences can be regarded. Voltage sag is one of the destructive issues in power quality problem to be taken into account. Not only can it have some undesirable effects on the sensitive load, but it also has some undesirable effects on synchronous machine as a power supply. In this study, SFCL was used in order to reduce the destructive effects of voltage sag on the performance of synchronous generators. To achieve better understanding, a simple model composed of synchronous generators, SFCL and load is used with the help of MATLAB/SIMULINK software. By creating voltage sag which results from 3-phase short-circuit voltage, current, torque, speed and angle load changes of synchronous generators were simulated and discussed. It was done in condition with/without SFCL. The results illustrate that using SFCL in synchronous generator output can improve its performance during occurrence of voltage sag.
Abstract: Electrical power quality has become an essential part of power systems and electrical machines. True identifying and regarding power quality and how to check the related destructive points are of utmost importance. Most of the time, providing the quality of power for sensitive load which requires the voltage to maintain a sinusoidal waveform at rat...
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A Compact Model of Mosfet Transistors Including Dispersion and Thermal Phenomena
Mohamed Ali Belaïd,
Ahmed Mohammad Nahhas,
Momamed Masmoudi
Issue:
Volume 3, Issue 6, December 2015
Pages:
192-197
Received:
24 August 2015
Accepted:
16 September 2015
Published:
7 December 2015
Abstract: This paper propose a new electro-thermal model nd presents a method of studying the thermal phenomena in power MOSFET transistors, utilizing Advanced Design System techniques by a Symbolic Defined Device (SDD). The model incorporates the thermal effects and the temperature evolution in the device and captures the heat dissipation from the silicon chip to the ambient air by providing three thermal capacitances and three thermal resistances (thermal network). It enables a better estimation of the device’s reliability and lifetime. Furthermore, it can be used to make a connection between the electrical parameter drifts and the existing failures types. The developed model reflects superior performance in terms of accuracy and flexibility and the results obtained indicate a good agreement with the operating conditions.
Abstract: This paper propose a new electro-thermal model nd presents a method of studying the thermal phenomena in power MOSFET transistors, utilizing Advanced Design System techniques by a Symbolic Defined Device (SDD). The model incorporates the thermal effects and the temperature evolution in the device and captures the heat dissipation from the silicon c...
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Risk Based Management Methods for Maintaining 750 kV Electricity Grid in Northwest China
Li Juan,
Liang Naifeng,
Zhao Puzhi,
Zhou Erbiao,
Li Xiaoguang
Issue:
Volume 3, Issue 6, December 2015
Pages:
198-201
Received:
11 December 2015
Published:
11 December 2015
Abstract: This paper will discuss a different case - a 750 kV transmission grid in China, in which the regulation rules have not been decided and the assets are operating in their early stage. The difficulty in technology and insufficiency of regulation decide the focus of this study: to select the method feasible in this business environment, rather than to develop complicated but unrealistic models.
Abstract: This paper will discuss a different case - a 750 kV transmission grid in China, in which the regulation rules have not been decided and the assets are operating in their early stage. The difficulty in technology and insufficiency of regulation decide the focus of this study: to select the method feasible in this business environment, rather than to...
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Considerations on Developing a Chainsaw Intrusion Detection and Localization System for Preventing Unauthorized Logging
Valentin Andrei,
Horia Cucu,
Lucian Petrică
Issue:
Volume 3, Issue 6, December 2015
Pages:
202-207
Received:
3 December 2015
Accepted:
11 December 2015
Published:
25 December 2015
Abstract: This work presents a system designed to prevent unauthorized logging by detecting and locating chainsaw sound sources. We analyze the specifics of chainsaw related sounds and discuss about the possible approaches for classifying the input sounds. The work also highlights several approaches for sound source localization that can be used in wireless sensor network architecture for tracking the assumed intruders. Finally we describe the architecture of the system and discuss on how our approach is designed to be scalable, fail-safe and cost effective.
Abstract: This work presents a system designed to prevent unauthorized logging by detecting and locating chainsaw sound sources. We analyze the specifics of chainsaw related sounds and discuss about the possible approaches for classifying the input sounds. The work also highlights several approaches for sound source localization that can be used in wireless ...
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Diagnosis of Water Tree Aging in XLPE Cable by the Loss Current Harmonic Component Under Variable Frequency Power
Chen Jie,
Li Hongze,
Zhou Li,
Hu Libin,
Li Chenying,
Cao Jingying
Issue:
Volume 3, Issue 6, December 2015
Pages:
208-214
Received:
8 January 2016
Published:
9 January 2016
Abstract: Water treeing is one of the main aging in XLPE cable insulation, which has the direct effect on the reliability of cable long-term operation. The diagnosis of water tree aging is a premise to ensure the safe operation of cables. The water treed XLPE insulation shows a nonlinear conductivity characteristic, which leads to a harmonic component in the corresponding lose current under the standard sinusoidal voltage. So the loss current harmonic component method can be an effective diagnosis of water tree aging. The loss current measurement system based on the high voltage current comparator bridge is used in this paper, which is designed by Harbin University of Science and Technology and Jiangsu Electric Power Company Research Institute. The feasibility of the application of variable frequency series resonant power source in the loss current measurement, which is aimed to diagnose the water treeing in XLPE insulation, is studied in the laboratory and field test. The results show that the output voltage waveform of the variable frequency series resonant power source is quite close to the standard sinusoidal voltage, although there are some high frequency sharp peaks. So the variable frequency series resonant power source can be used as the high voltage test power supply in the loss current harmonic component measurement system. The loss current harmonic component has power frequency interference during the field test, but this can be solved by differential frequency principle. The microscopic observation of water tree structures during the anatomy of the cable not only indicates the effectiveness of the results and diagnosis during the field test, but also proves the feasibility of the application of variable frequency series resonant power source in the loss current measurement. The existence and degree of the water tree can be estimated according to the test results, which can be a strong basis of the standardization of water tree aging diagnosis. Furthermore, the expensive standard sinusoidal wave generator and linear power generator is replaced by the variable frequency series resonant power source, which reduces the cost and weight of the testing system.
Abstract: Water treeing is one of the main aging in XLPE cable insulation, which has the direct effect on the reliability of cable long-term operation. The diagnosis of water tree aging is a premise to ensure the safe operation of cables. The water treed XLPE insulation shows a nonlinear conductivity characteristic, which leads to a harmonic component in the...
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