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.
The polluted insulators problem is one of the most important cases, that faces the electrical networks especially in Syrian Arab Republic because the sources of pollution expand more and more, On the other side, the electrical power supply is related
to the operation of all commercial and daily sectors.
The environmental pollution on the insulators generally causes general breakdowns in the electrical power supply networks of wide areas, This makes great economical losses in all sectors that are related to electrical network.
In this research, the distinct values of insulators pollutions are defined. We then find the relationship between the mentioned values and flashover voltage of polluted insulators in the laboratory. The results of the tests apply on the natural polluted insulators in the outsides. Finally, comparison measurements are made on naturally polluted insulators, and the appropriated procedures to limit the pollution effects .
The objective of this work is to study and design a module of super capacitors for recovering the braking
energy in trolleybuses. The module of super capacitors is charged and discharged by Buck-Boost
converter that is reversible in current. The co
ntrol and the smoothing elements of the converter are
designed with taking into account the non-linear nature of super capacitors. To recover quickly the
braking energy, the module is charged with constant current, while the discharging is done with constant
voltage on the DC link of trolleybus. The module of super capacitors in its different operations (starting
up, powering auxiliary equipments, braking) is simulated in the SIMPLORER environment. As a result,
the different operating values (as voltage, current and temperature) are determined for the elements of
the studied module (diodes, IGBTs, capacitor, super capacitors). Finally, the failure rate and the
reliability of the module elements are estimated depending on the different operating factors. The module
faults is analyzed.
Kouttina is one of the most proper areas in Syria for building wind energy conversion system. This system could be coupled with Syrian electrical grid without expensive cost because of nearing from the grid. But the permanent changes of wind speed wi
th no stable mode, cause different amplitude and frequency voltages differ from Syrian electrical grid amplitude and frequency.
The goal of this research is to design proper wind energy conversion system for Kouttina area and control it, therefore we always obtain constant amplitude and frequency voltages equal to those of Syrian electrical grid for any wind speed and load.
The proper wind turbine with its generator was chosen depending on parameters of probability mathematic function, called Wiebull Function. After that the proper control system was designed for equaling the amplitude and frequency of wind energy conversion system output with those of Syrian electrical grid. The buck -boost converter was controlled by proportional integral (PI) controller to always have DC output voltage equal to (622V). While the inverter controller was achieved by using two PI control loops, the outer loop for voltage control and the inner loop for current control. Though, three phase voltage with RMS phaser value of (220V) and frequency value of (50Hz) is achieved.
To validated the correctness and effectiveness of the proposed system, it was modeled using MATLAB program. The results showed the system ability of obtaining voltage with constant amplitude and frequency and this values do not change with wind speed or load changes.
The main aim of the extension of electrical cables is to transmit electric
power between the components of electric power system, which include generating, distributing, transporting and investing the system with the best possible performance.
In t
his paper, we will show the general principles which enable us to
choose the suitable cable-section in accordance with the economic and
technical feasibility. In this study, we develop two algorithms : the first
algorithm takes into account the technical study, while the second
concentrates on economic study and then the final section of the cable is selected as a result of both studies.
This study aims to analyze the effect of the wind farms on frequency stability of the electrical power network, and the description of the performance of Syrian Electrical Power System with integration of
wind farms in several regions in Syria (Al-Q
uenetera – Al-Hejana - Ghabagheb) through the evaluation of frequency stability of the power system and the Critical Clearing Time (CCT).
The effect of wind farms on the frequency behavior of Syrian network and factors related will be investigated such as generation technology by replacing the power-generated source by two main types
of induction generators, changing the location of wind farms and increasing gradually the rate of wind power.
The simulation analysis will be applied on Syrian Electrical Power System 230KV – 400KV, by using program NEPLAN, which gives access to an extensive library of grid components, and relevant wind
turbine model.
This research aims at studying types of PV Systems and their applications in many practical
fields. It also aims at looking into all the components and technical specifications of the
equipment. That's what serves these systems' design and implemen
tation ways through
designing and performing a 12 [KW] Stand- alone PV System. This system is usually used to
supply one of the Green Buildings lighting at night with a back- up grid to achieve a high
reliability in supplying the load. This project also aims at strengthening national qualifications
in the fields of research, development and operation.
The turbine control purpose is to achieve the maximum limit of wind power,
associated with reducing the mechanical loads. The current control techniques do not take
into consideration the dynamical side of wind and turbine, which leads to power los
s. To
improve the effectiveness of the
nonlinear controllers, we can derive the nonlinear feedback controllers for static and
dynamic conditions in order to reach the wind speed estimator. Then we can test the
controllers by a mathematical model applied on the wind turbine simulator, with
disturbances and noise. The results have shown important improvements in comparison
with the current used controllers.
This paper presents the effects of enhancing control systems' work conditions on active power filter performance in improving power quality. We will convert the changeable inputs of the controllers into static ones. The high harmonics' amplitude will
be the set-values of the controllers, so the active filter reduces them into zero and then THD will be in its permitted limits.
The re-use of return air in central conditioning systems is one of the most important
procedures for saving power consumption. However, the requested fresh air of the people
existed within the conditioning space imposes determining the number of ti
mes to be used.
This research aims to link the work of the central conditioning system (heating) of a
facility with the number of people existing within this facility by modifying the ratio of
mixed fresh air and return air to save the electrical power consumption. Also, to raise the
temperature of the mixture air by controlling the flow of hot water continuously rather than
using on-off technique. As well as, to respond to any change in the number of people and
get rid of repeated machine starting.
Our research has been done by using specialized physical model consisted of test
room, heat and movement sensors, pump, water tank, heat exchanger and air mixing
blades. These devices are controlled by microcontroller type PIC16F877A.
The experimentally obtained results showed the ability of controlling the amount of
return air depending on the number of people and controlling the speed of the pump
continuously providing a saving of electrical energy consumption up to 68% compared
with the case of full speed.
