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Article
Estimation of the Consumer Peak Load for the Iraqi Distr ibution System Using intelligent Methods

Authors: M. A. Al-Nama --- M. S. Al-Hafid --- A. S. Al-Fahadi
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2011 Volume: 7 Issue: 2 Pages: 180-184
Publisher: Basrah University جامعة البصرة

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Abstract

The drastic increase of residential loadconsumption in recent years result in over loadingfeeder lines and transformers for the Iraqi northernarea distribution system especially in the city of Mosul.Solution for this problem require up to date researchconsumers load study to find the proper solution to stopexcess overload in the transformers and the feeders. Thispaper include the regional survey for samples ofconsumers representing typical types of differentstandard of living and energy consumption bydistributing questioners contain list of information suchas load type in daily use. Also current readings arerecorded for the individual consumer for the months ofthe year 2006. In addition to those readings, energyconsumption is recorded once every two months.The registered readings are used in conjunction withthe list of questionnaires to find a sample (for differentloads) that coincide with the list of questionnaires forcurrent and energy readings. Resulting in the feasibilityof using the sample to know the peak value of currentfor any consumer even if he is not included in the list ofquestionnaires and for any new consumer, since itbecome possible to decide the size of the transformersand feeder lines, to overcome the problem of overloadingin any part of the distribution system. The ArtificialNeural Network (ANN) is used in this paper to find theabove mentioned sample.


Article
Al - Kalij Sub-Station: Feeder Reconfiguration by Particle Swarm Optimization

Authors: Qais M. Alias --- Rana Ali Abttan
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 12 Pages: 2375-2385
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This paper presents the solution approach for the optimal reconfiguration problemin distribution networks implementing Particle Swarm Optimization (PSO)technique.Network reconfiguration in distribution system is changing the status ofsectionalizing switches to reduce the power loss in the system. The main objective ofnetwork reconfiguration is to find the network topology which is having theminimum losses during any conditions exists in the network. A networkconfiguration is a valid solution to the problem if it satisfies reliability, security andother operation constraints.Particle Swarm Optimization is a robust stochastic evolutionary computationtechnique, which is based on the movement and intelligence of swarms.A standard particle swarm optimization algorithm is adapted and used in this work.The primary case study is a part of the Baghdad area distribution network. It consistsof four feeders and 102 buses. The algorithm validity is verified first via applicationto standard systems. Results show that the standard particle swarm optimization issuitable for off-line reconfiguration studies.


Article
Electric Distribution System Reconfiguration For Loss Reduction Using Genetic Algorith

Author: Mrs. Rana Ali Abttan
Journal: Journal of Baghdad College of Economic sciences University مجلة كلية بغداد للعلوم الاقتصادية الجامعة ISSN: 2072778X Year: 2015 Issue: 43 Pages: 457-478
Publisher: Baghdad College of Economic Sciences كلية بغداد للعلوم الاقتصادية

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Abstract

This paper presents the solution approach for the optimal reconfiguration problem in distribution networks implementing genetic algorithm technique. Network reconfiguration in distribution system is changing the status of sectionalizing switches to reduce the power loss in the system. The main objective of network reconfiguration is to find the network topology which have the minimum losses during any conditions exists in the network. A network configuration is a valid solution to the problem if it satisfies reliability, security and other operation constraints.A genetic algorithm is adapted and used in this work. The primary case study system is a part of the Baghdad area distribution network. It consists of main feeder, 6 laterals feeders and 48 buses. The algorithm validity is verified first via application to standard systems. Results show that the genetic algorithm is suitable for off-line reconfiguration studies.

يقدّمُ هذا البحث طريقة لحَلَّ مسألة إعادة التشكيل المثاليةِ في شبكاتِ التوزيع الكهربائية. استخدمت تقنية الخوارزميات الجينية (genetic algorithm ) لحَلَّ المسألة اعلاه.اعادة تمثيل الشبكة في نظامِ التوزيعِ يعرف بتَغيير حالة مفاتيح الفصل(sectionalizing switches) لغرض تقليل الخسائر الكهربائيةِ في النظامِ. إنّ الهدفَ الرئيسيَ لاعادة تشكيل الشبكة هو ايجاد طوبوغرافية الشبكةَ التي سَيكونُ فيها اقل الخسائرُ أثناء أيّ ظرف عمل في الشبكةِ. حورت الخوارزمية الجينية واستَعملتُ في هذا العملِ. استخدمت شبكة ذات مغذي رئيسي , ستة فروع و48 عمومي كجزء من شبكة بغداد- الرصافة للتوزيع. تم تصديق الخوارزميةَ أولاً عن طريق التطبيقِ على أنظمةِ قياسيةِ ومطابقة للنتائج. الاستنتاج الاساسي هو امكانية استخدام طريقة الخوارزمية الجينية لحَلَّ مسألة التشكيل الامثل لمنظومات التوزيع.


Article
An Improved Newton Method For Radial Distribution System Load Analysis

Author: Hassan A. Kubba
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2006 Volume: 12 Issue: 4 Pages: 1122-1135
Publisher: Baghdad University جامعة بغداد

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Abstract

This paper presents a modified Newton method of load flow analysis for radial distribution systems. It is derived with the Jacobian matrix is in UDUT form, where U is a constant upper triangular matrix depending solely on system topology and D is a block diagonal matrix. With this formulation, the conventional steps of forming the Jacobian matrix, LU factorization and forward/back substitution are replaced by back/forward sweeps on radial feeders with equivalent impedances. The method has advantages over Newton’ s method in terms of speed of solution (no. of iterations), and reliability of convergence by inserting a minimization technique (Cubic Interpolation Technique). The algorithm exhibits a control of the convergence. As such the method converges for cases when conventional Newton’ s method and some other popular methods diverge. Two large distribution systems of 490 nodes and 722 nodes with different r/x ratio in line impedance are used to examine the performance of the method. These tests have shown that the proposed method is as robust and efficient as the forward/back sweep method. The proposed method can be extended to the solution of three phase unbalanced representation.

يقدم البحث طريقة نيوتن-رفسن مطورة لتحليل انسيابية الاحمال الكهربائية لانظمة التوزيع الشعاعية. الطريقة المقترحة في البحث اعتمدت على ان مصفوفة الجاكوبين تكون بشكل ( (UDUT حيث ان مصفوفة [ U ] تمثل مصفوفة مثلثية علوية ثابتة تعتمد على طوباغرافية المنظومة بينما مصفوفة [D] تمثل مصفوفة قطرية. من خلال هذه الصيغة، فان الطريقة التقليدية لاعداد مصفوفة الجاكوبين وهي طريقة التحليل العلوي-السفلي ( LU ) والتعويض ( ( forward/back قد استبدلت بطريقة ( (back/forward sweeps على المغذ يات الشعاعية بممانعات مكافئة. الطريقة المقترحة في البحث لها افضلية وفوائد على طريقة نيوتن-رفسن التقليد ية في عدة معايير وهي سرعة الوصول الىالحل ( عدد العمليات التكرارية ), ووثوقية الوصول الى الحل من خلال استخدام تقنية التضئيل واستخدام عامل التصحيح ( α) . ان خوارزمية الطريقة المقترحة تقدم سيطرة على عملية الوصول الى الحل الموثوق لانظمة مختلفة التعقيد بينما طريقة نيوتن-رفسن التقليد ية وطرق اخرى شائعة تفشل في الوصول الى الحل. استخدم نظامان كبيران لتوزيع الطاقة الكهربائية وهما (490 عقدة و 722 عقدة ) ذو نسب مختلفة مقاومة/محاثة لخطوطالتوزيع لتقييم اداء الطريقة المقترحة. الدراسة اظهرت قوة وكفاءة الطريقة المقترحة في البحث, كما يمكن استخدامها في انظمة احادية الطور وانظمة ثلاثية الاطوار غير المتوازنة.


Article
A Proposed Algorithm for Reactive Power & Voltage Coordination in Distribution Systems Using Fuzzy Technique
خوارزمية مُقترحة لتنسيق القدرة المتفاعلة و الفولتية في منظومات التوزيع باستخدام التقنية المضببة

Authors: Aws Habib Mohammed --- Afaneen Anwar Al-Khazragy
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 12 Pages: 2447-2464
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This method finds the Under Load Tap Changer (ULTC) position andcapacitor ON/OFF status of each hour for the next day in main or secondarydistribution substations, so the secondary bus voltage improves and the reactivepower flow into the transformer can be restrained at the same time. The onlycondition to achieve these goals is the previous knowledge (by forecasting) ofload demand for active and reactive power and the primary bus voltage for eachhour of that day. The practical constraints are involved through the use ofmembership concept in fuzzy set theory, where these constraints are bus voltagelimits, the tolerable worst power factor & the maximum allowable number ofswitching operations for the Load Tap Changer (LTC) and capacitor in a day. Thismethod is also considering the variation of load active & reactive power with itsvoltage, where the loads are classified into three categories according to theirrelationship with voltage, and so there are constant impedance loads, constantcurrent loads and constant power loads. To demonstrate the usefulness of thismethod an example on one of the Iraqi national grid substations (132/33KVYarmook substation) was made in MATLAB.

تجد هذه الطريقة موقع مغير الفولتية تحت الحمل وحالة اشتغال أو إطفاء المكثف لكلساعة من اليوم التالي في محطات التوزيع الرئيسية أو الثانوية, وهكذا تتحسن الفولتية و تُقننالقدرة المتفاعلة المارة بالمحولة في الوقت نفسه . الشرط الوحيد لتحقيق هذه الأهداف هوالمعرفة المسبقة ( باستخدام التنبؤ ) بمقدار طلب الحمل من القدرة الفعالة والمتفاعلة وفولتيةالملف الأبتدائي للمحولة لكل ساعة من ذلك اليوم. المحددات العملية يتم تضمينها من خلالاستعمال مفهوم العضوية في نظرية المجموعة المضببة , حيث أن هذه المحددات هي حدودالفولتية , أسوء معامل قدرة مسموح به و أقصى عدد مسموح به من عمليات تغيير موقع مغيرالفولتية تحت الحمل والمكثف في اليوم الواحد. وكذلك تأخذ هذه الطريقة بنظر الاعتبار تغيرالحمل كقدرة فعالة و متفاعلة مع فولتيته , حيث تصنف الأحمال إلى ثلاث فئات طبقاً لعلاقتهامع الفولتية , وهكذا هناك أحمال الممانعة الثابتة , أحمال التيار الثابت و أحمال القدرة الثابتة .لغرض التوضيح المفصل عن فائدة هذه الطريقة تم عمل مثال على واحدة من محطات الشبكة.MATLAB 33 ك.ف.) باستخدام ال الوطنية العراقية (محطة اليرموك 132


Article
Optimal Conductor Selection in Radial Distribution Systems for Productivity Improvement Using Genetic Algorithm

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Abstract

Development of distribution systems result in higher system losses and poor voltage regulation. Consequently, an efficient and effective distribution system has become more urgent and important. Hence proper selection of conductors in the distribution system is important as it determines the current density and the resistance of the line. This paper examines the use of different evolutionary algorithms, genetic algorithm (GA), to optimal branch conductor selection in planning radial distribution systems with the objective to minimize the overall cost of annual energy losses and depreciation on the cost of conductors and reliability in order to improve productivity.Furthermore, The Backward-Forward sweep iterative method was adopted to solve the radial load flow analysis. Simulations are carried out on 69-bus radial distribution network using GA approach in order to show the accuracy as well as the efficiency of the proposed solution technique.


Article
Effect of Parallel Distributions System on Computer Efficiency and Performance
تأثير نظام التوزيعات المتوزاية على كفاءة الحاسوب وادائه

Author: Jehan K. Shareef جيهان كاظم شريف
Journal: Univesity of Thi-Qar Journal مجلة جامعة ذي قار العلمية ISSN: 66291818 Year: 2014 Volume: 9 Issue: 4 Pages: 1-12
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

In this paper, the distribution parallel system tool MPI (Message Passing Interface) to solve squared matrixes product was used. In order to make parallel tasks, the work will be implemented at least by using two computers. Also, several tasks will be included in this project to estimate the Speedup of the processor (p), Efficiency of the processor (p), fraction f of sequential work and fraction of parallel part of the work using Amdahl’s law. Moreover, this paper will estimate many approaches which are: running the application on 1 processor for 3 different values of matrix elements N (for example 1000× 1000, 2000 × 2000, and 3000 × 3000), running the application on 2, 3 or more processors for the same values of N, estimating fraction f of sequential part, estimate f for 3 different values of N by having measured times, finding out whether this fraction depends on the problem size N, and more operation to complete the task required

في هذا البحث تم استخدام اداة نظام التوزيع المتوازي MPI (Message Passing Interface) لحل مسألة ضرب مصفوفتين مربعة ذات ابعاد كبيرة. من اجل تنفيذ النظام المتوازي ، تم تطبيق العمل على كومبيوترين على الاقل . كذلك هذا البحث يتضمن تخمين سرعة الكومبيوتر ،كفائته ، وايجاد نسبة وقت التنفيذ في كومبيوترواحد الى وقت التنفيذ في كومبيوترين ( f fraction ) باستخدام قانون Amdahl. العمل نفذ على كومبيوتر واحد مع تغيير حجم المصفوفة المربعة (مثلا بحجم 1000×1000، 2000×2000 ، 3000×30000 ) ومن ثم على كومبيوترين وايجاد وقت التنفيذ في كل حالات الاختبار وتحديد هل ان ( f fraction ) يعتمد على حجم المصفوفة ام لا. اضافة الى العديد من العمليات التي تم اختبارها لاكمال هذا البحث .


Article
Multi-Pulse Diode Rectifier for More-Electric Aircraft Applications: Parallel versus Series Topologies

Authors: Ahmed A. A. Hafez1,2 --- Ali M. Yousef
Journal: Iraqi Journal for Electrical And Electronic Engineering المجلة العراقية للهندسة الكهربائية والالكترونية ISSN: 18145892 Year: 2017 Volume: 13 Issue: 1 Pages: 138-144
Publisher: Basrah University جامعة البصرة

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Abstract

This article analyzes thoroughly the performance of the Multi-Pulse Diode Rectifiers (MPDRs) regarding the quality of input/output voltage and currents. Two possible arrangements of MPDRs are investigated: series and parallel. The impact of the DC side connection on the performance of the MPDRs regarding the operation parameters and rectifier indices are comprehensively examined. Detailed analytical formulas are advised to identify clearly the key variables that control the operation of MPDRs. Moreover, comprehensive simulation results are presented to quantify the performance and validate the analytical analysis. Test-rig is set up to recognize the promising arrangement of MPDRs. Significant correlation is there between simulation and practical results. The analytical results are presented for aircraft systems (400Hz), and power grid systems (60Hz). This is to study the impact of voltage and frequency levels on the topology type of MPDRs. In general, each topology shows merits and have limitations.


Article
OPTIMAL CAPACITOR PLACEMENT TO REDUCE ACTIVE POWER LOSSES AND HARMONIC IN UNBALANCE DISTRIBUTION SYSTEM

Author: Inaam Ibrahim ALI
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2017 Volume: 10 Issue: 3 Pages: 274-290
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

This paper proposed an algorithm to find the best location of shunt capacitor and size to reduce the total active power loss and harmonics consideration after assuming electric arc furnace (EAF) in the unbalanced radial distribution network. Demonstrated the results by using practical software (CYMDIST) as a tool, to determine power flow and find the best capacitors size and location that decrease power loss and improve voltage profile. The total harmonic voltage distortion at system does not exceed the maximum allowable total harmonic voltage distortion level (THVD%) compared with IEEE-standard 519-1992. To attain the goal of this algorithm, these algorithms are tested in 25-buses un-balanced radial distribution system and an actual part of Baghdad city distribution network that is content 66-bus for Al_JIHAD_feeder_5 11 kV network are depicted for the implementation of this analysis.


Article
CONTINUATION POWER FLOW OF AN UNBALANCED THREE-PHASE FOUR-WIRE DISTRIBUTION SYSTEM

Authors: Alaa Saad Hussain --- Dr. Kassim Abdulrezak Al-Anbarri
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 2 (Part-1) Pages: 56-71
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

A continuation power flow algorithm for an unbalanced three phase four wire distribution system is presented. The proposed algorithm is used to trace the loci of the voltage of the different phases of an unbalanced three-phase distribution system. The locus of the neutral voltage for a wide range of loading conditions is also obtained. The proposed technique is applied on a typical unbalance three phase radial Iraqi distribution system. The results obtained reveal the effectiveness of the continuation technique for exploring all the possible solutions and the determination of maximum loadability of the distribution feeder.

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