Keeping the voltage within the required limits is one of the key issues of operating a power system. since the voltage in electrical power system is affected significantly by changes of loads and
equivalent circuit of the power system, there is a ne
ed to regulate the voltage with high control ability. Because of the growing use of FACTS in General and STATCOM among them in power systems to improve voltage stability, and because of the need for software that is not always available, the aim of research is to develop a mathematical model, algorithm and software for load flow analysis at the steady state of power system includes static synchronous compensator STATCOM.
The Jacobian matrix in the Newton –Raphson algorithm, which is the relationship between voltage and power mismatches, is extended with the STATCOM variables to adjust the voltage and control of the reactive power witch is injected or absorbed at the point of common coupling, with high controlability.
A Complete software has been developed that includes comprehensive control facilities and exhibits very strong convergence characteristics. A Sophisticated algorithm has been verified and the effectiveness of the program is tested by its application to a number of standard power systems
including the IEEE 5-bus system, and Syrian transmission network 400 kV.
with different frequency make Voltage Source Converter - HVDC link (VSC-HVDC links) an
attractive technology for most power transport in meshed grids. Advantages are the high
controllability of active and reactive power at the converter’s terminals
and the ability to increase the
stability of the surrounding AC system. VSC-HVDC can provide active and reactive control to achieve
maximum power transfer, system stability and improve power quality and reliability.
This research aims to develop a mathematical model and an algorithm for the analysis of power flow in
a steady state of power system containing VSC-HVDC.The Jacobian matrix inNewton-
Raphsonalgorithm, which is the relationship between voltage and power mismatches, is extended with
the VSC HVDC variablesto control active and reactive powers and voltage magnitude in any
combination. A Newton-Raphson load flow program has been developed which includes
comprehensive control facilities and exhibits very strong convergence characteristics. Two scenarios
have been studied, back-to-back VSC-HVDC link and full VSC-HVDC link connecting two buses in
AC networks. The algorithm and the program have been verified through a number of simulation
examples carried out on IEEE 14-bus System.
Unified Power Flow Controller (UPFC) plays a vital role in improving the power system
performance, both the static and dynamic, and enhanced the system loading capability by
rerouting the power flow in the network.
This paper presents control and
performance of UPFC intendedfor installation on the
transmission line to control power flow and improve voltage profile.
في هذا البحث تم تطوير هام للنظام البرامجي 1 Security لتحليل أمان نظام القدرة الكهربائية الذي كان
قد قُبل للنشر في مجلة جامعة دمشق. النظام البرامجي 2 Security الجديد لا يقوم فقط بتحليل الأحداث
المحتملة التي يمكن أن يتعرض لها نظام القدرة الكهربائية م
ن حيث جريان الاستطاعة الفعلية، و يكشف
الخطوط المحمَّلة تحميلاً زائداً، بل يستخدم أيضاً تقانة البرمجة الخطية لتعديل استراتيجية التوليد و تقنين
بعض الأحمال كإجراء تصحيح وقائي لإزالة التحميل الزائد عن الخطوط المرهقة. لقد تم تصميم النظام
البرامجي بلغة تربو باسكال و وفق شاشات حوار مع المستخدم، و تم التثبت من صحته بتطبيقه على شبكات
عملية اختبارية، كما استخدم لتحليل الأمان لجزء من الشبكة السورية لتوتر 230 ك ف. و تبين من خلال
النتائج أن البرنامج فعال و مرن و قادر على تنفيذ وظائفه بدقة مقبولة و سرعة قياسية على الرغم من
استخدام النماذج الخطية في بنائه.
The paper begins with an introduction that describes the concept and
importance of power system security. The mathematical model is built
depending on both the linear load flow technique and the sensitivity
factors for line and generation outages.
The algorithm has been designed
so that a power system of arbitrary bus number and voltage levels can be
studied. This algorithm has been programmed in Borland Pascal in
interactive mode, and the developed program has been tested on several
test systems. The Program has been used for security assessment of a part
of the Syrian 230 kV network. The obtained results have shown the
validity and effectiveness of the program in spite of using linear models.
It is worth saying that the developed program is the first one for security
assessment in Syria so far.
Phase Shifting Transformer has played an important role in electrical networks to improve
their efficiency because it has the ability to control power flow in electrical transmission network
that can lead to power loss minimization. PST technology
is considered as mature technology
which is used by transmission system operators. These transformers provide an integrated solution
to control power due to the advantages of low economic and high reliability.
In this research an exposure to the classification of phase shifting transformers and their
application then a simple model for Phase shifting transformer is suggested without seeking in the
details of transformer, this model presents the result for using PST via modeling phase shifting
voltage, this model is performed using Matlab/Simulink program according to differential
equation. Depending on the mathematical model which has been built in an Matlab environment
we have a model shows the impact of this transformer through the representation of output voltage
, results are verified using Neplan program via a case study demonstrated the role of this type of
transformers in controlling power flow in transmission system achieving remarkable power loss
reduction and improving voltage profile
The use of DC and especially VSC-HVDC systems are
considered as urgent and important in electrical networks to
improve their efficiency because they have great benefits not only in
connecting different frequency networks and connecting the
renewa
ble energy to the network, but also control power flow in a
way that reduce the losses and achieve the optimal flow electrical
networks especially in networks that contain more than one energy
supplier and thus can achieve economic benefits as well as the
scheduling of importing energy from another that may improve
network stability.
Types of HVDC system and a comparison between them are
achieved in this research after that simulation IEEE with VSCHVDC,
and integrated computer program was proposed this
program can create and store three-dimension matrix so the working
area can be scanned so minimum loss working point can be
detected.
