Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userImpact of Reactive Compensators on Performance of Distance Protective Relays
أثر معوضات الاستطاعة الردية في أداء حواكم الحماية المسافية
2344
2 58
0
(
0
)
Created by
Shamra Editor
Ask ChatGPT about the research
حاولت هذه الدراسة بيان مشكلة الأثر الناجم عن وجود المعوضات التفرعية و التسلسلية في خطوط نقل القدرة الكهربائية في أداء حواكم الحماية المسافية التي تحمي هذه الخطوط. و من أجل بيان هذا الأثر استخدمت برمجيات تحليل الشبكات الكهربائية و بشكل خاص برنامج NEPLAN لدراسة سلوك الحاكمة المسافية بوجود مختلف أنواع المعوضات التفرعية و التسلسلية، و من أجل الأعطال الأساسية، و عند مواقع مختلفة من الخط المدروس. ي هذه الدراسة أجرِيت نمذجة شبكة نقل الطاقة السورية وفق NEPLAN و استخدمت معوضات تفرعية مثل STATCOM و تسلسلية مثل TCSC ومختلطة مثل UPFC لتعويض الاستطاعة الردية على خط النقل المحمي . و تُجرى النمذجة لكثير من الحالات، لبيان أثر نمط العطل و موضعه في قيمة الممانعة المقيسة من الحاكمة المسافية. و الغرض من تحديد أثر وجود المعوضات في ممانعة العطل المنظورة من الحاكمة المسافية (أي موضع العطل)، هو معرفة الاتجاهات الممكنة لحل لهذه المشكلة و تحسين أداء حمايات خطوط نقل الطاقة الكهربائية.
This paper tries to clarify the impact of parallel and serial compensation of power transmission lines on the performance of distance relays which protect these lines. To this end, power system analysis software (NEPLAN) will be used for explaining distance relay behavior in the presence of different parallel or serial reactive power compensators, with main types of faults that may occur in different locations on the protected line. In this paper, Syrian power transmission network is simulated using (NEPLAN) software, and three reactive power compensators: parallel (STATCOM), serial (TCSC), and unified (UPFC), are used to compensate reactive power on transmission line. Several simulations, in many cases are carried out to illustrate the impact of fault type and location on the measured impedance seen by the distance relay. The objective of identifying the impact of reactive compensators on fault impedance seen by distance relay (i.e. fault location), is to determine the possible ways to resolve the problem and improve the performance of transmission line protection.
References used
Yongan Deng. “ Reactive Power Compensation of Transmission Lines” Concordia University. 2007
Abhijit C, Sunita H. “ Power System Analysis Operation and Control”, third edition ,PHI Learning Private Limited, 2010
Zellagui M, Chaghi A , “Impact of GCSC on Measured Impedance by Distance Relay in the Presence of Single Phase to Earth Fault” , LSP-IE Research Laboratory, 2012
Manokaran T, karpagam V. “Performance of Distance Relay Estimation in Transmission Line with UPFC”. International Journal of Computer and Electrical Engineering, 2010
Zhou X.Y, Wang H.F, Aggarwal R.K, Beaumont P. “The Impact Of STATCOM On Distance Relay”. 15th PSCC, 2005
rate research
Read More
Reactive power compensation in distribution networks is one of the most important economic and
environmental issues in power system studies. In this paper the following points are investigated:
· The characteristics of the most developed equipment
used for reactive power compensation.
· Equations used in ETAP program calculation
· OCP is part of ETAP program which gives us the possibility to determine optimal reactive power
sizing and placement in distribution networks in order to achieve optimal Power loss and distribution
power system enhancement.
· ETAP program is applied on a part of Damascus suburb electrical network which was simulated by its
real parameters and the positive economical and technical results have been clarified.
The aim of this study to identify the impact of ownership’ structure criteria measured by
managerial ownership and ownership dispersion on corporate performance measured by
return on equity ROE, through sample contains of six Syrian private banks a
nd six Syrian
insurance companies for period between 2011 and 2016. The results showed that the
managerial ownership effects on performance, while ownership dispersion does not affect
on performance, as well as the relationship between these variables difference in term of
industry the company belongs to. To enhance the performance of Syrian corporation, some
recommendations have been presented by the end of study.
Ad-hoc networks has opened a new dimension in wireless networks. It allows
wireless communication in the absence of central support of the contract. In these
networks, there are no fixed infrastructure because the mobile nodes are continuously
mak
ing continuous and dynamic change in the topology.
Routing protocols of mobile ad-hoc networks differ from the existing internet
protocols which are designed for the fixed structure based wireless networks. MANET
protocols have to face high challenges due to dynamically changing of topologies, low
transmission power and asymmetric links. Due to link instability, node mobility and
frequently changing topologies routing becomes one of the core issues in MANETs.
Currently existent routing protocols provide routing solutions up to a certain level
and most of them are designed and implemented in small areas. Many researchers are still
working on the developments of MANET routing protocols.
With the increase in the types of routing protocols used in mobile network it has
become necessary to study the effectiveness of each type of protocols In this papper we
compared between the most famous species (proactive, Reactive, hybrid) and choose a
protocol to be representative of all species previously mentioned and the network
performance assessment each type in terms of Throughput, dynamic routing routing, load,
delay and determine which of these protocols appropriate for each case.
This research aims to shed light on the impact of corporate governance on the performance
of listed companies in Damascus Securities Exchange (2012-2016). To achieve this
objective, the researcher used a hypothetical-deductive approach to formulate
the
hypotheses; and analyzed the financial statements of all shareholding Syrians listed
companies. Results indicate that, despite of the variation in applying corporate governance
between listed companies, there is a sufficient level of commitment to the principles of
corporate governance. As well as, the results showed that all performance indicators
effected by corporate governance principles. The results of this study provides an empirical
evidence to policy makers and regulators in Syria to emphasize the importance of the
continuation of Syrian companies to abide by the applying of the principles of corporate
governance; as well as the need to find a unified measure corporate governance can be
applied in Syria; and at the same time the need to educate the public concerning corporate
governance.
This research focuses on the phenomenon of diversity and multi-culture through the work environment of the ministry of industry, through the behavior of individuals and how different the culture and the diversity of ideas, skills and creativity and
its impact on performance.
The researcher depends on a sector of workers at the ministry of industry consisted of (150) workers on top of their work during the sixth month of the current year (2013) in order to identify the impact of the manifestations diversity (both demographic and cultural in this environment) on the performance of workers.
The researcher used the analytical method and descriptive manner in the analysis of data prepared in accordance to juried survey and is composed of two main pillars, first of the manifestations of diversity (demographic and cultural) in the work environment, and the other of productivity, using certain statistical methods: Test (T-TEST) for two independent samples, and testing of variance (ANOVA), and the alpha-Cronbach coefficient to test the stability of scale search tool. The search found the following results:
- The manifestation of the demographic diversity does affect positively the performance of workers at the ministry of industry except for the working status doesn't affect the performance.- The manifestation of the demographic diversity affects positively the productivity of workers at the ministry of industry.
The researcher recommends the following:
- The need to absorb the concept of aspects of demographic diversity and cultural diversity as an important concept in the present time in all public sectors.
-The necessity of activating the role of human resources management at the ministry of industry.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
