Salah Eldeen Gasim

The power quality problems in power utility distribution systems are not new, but recently their effects have gained public awareness. Advances in semiconductor device technology have fueled a revolution in electronics and power electronics over the past decade, many factories and heavy loads which are recently installed highly affect power quality due to their nonsinusoidal current. In this paper different harmonics sources such as electric ballast, magnetic ballast, vapor mercury, halogen spot light and halogen with dimmer and their effects and two methods of harmonics elimination are studied. The results obtained show that at incidence of harmonics the currents waveform are not sinusoidal, THD values are out of limits, there is a set of high order harmonics, the current values are higher and power factor is lower. However, the results obtained when the harmonics are eliminated show that THD values are reduced, the currents values are reduced, the power factor is improved and valu...

The continuous increase of power demand stresses the system, and adversely affects its security. It may lead to components overload and their outage, voltage decline and its collapse, which may cause entire system blackout. As well, the normal flow of power in transmission lines is not the best possible. In this paper, the Phase Angle Regulator (PAR) and Sen Transformer (ST) are suggested to be used for better utilization of the transmission lines, and to enhance power system security. In this work, the PAR and ST are modelled, and connected in a five bus test system using MATLAB/SIMULINK. The simulation results showed validity of both PAR and ST, and the superiority of ST, since it enhances both power flow and voltage security. Based on the results, the new emerging smart power and voltage control device ST is a very effective tool that can be combined into Smart Grids (SGs). It is found that, usage of ST not only manages line flow congestion and maintains bus voltage, but also inc...

The power quality problems in power utility distribution systems are not new, but recently their effects have gained public awareness. Advances in semiconductor device technology have fuelled a revolution in electronics and power electronics over the past decade, many factories and heavy loads which are recently installed highly affect power quality due to their nonsinusoidal current. In this paper different harmonics sources such as electric ballast, magnetic ballast, vapor mercury, halogen spot light and halogen with dimmer and their effects and two methods of harmonics elimination are studied. The results obtained show that at incidence of harmonics the currents waveform are not sinusoidal, THD values are out of limits, there is a set of high order harmonics, the current values are higher and power factor is lower. However, the results obtained when the harmonics are eliminated show that THD values are reduced, the currents values are reduced, the power factor is improved and val...

ABSTRACT The continuous increase of power demand stresses the system, and adversely affects its security. It may lead to components overload and their outage, voltage decline and its collapse, which may cause entire system blackout. As well, the normal flow of power in transmission lines is not the best possible. In this paper, the Phase Angle Regulator (PAR) and Sen Transformer (ST) are suggested to be used for better utilization of the transmission lines, and to enhance power system security. In this work, the PAR and ST are modelled, and connected in a five bus test system using MATLAB/SIMULINK. The simulation results showed validity of both PAR and ST, and the superiority of ST, since it enhances both power flow and voltage security. Based on the results, the new emerging smart power and voltage control device ST is a very effective tool that can be combined into Smart Grids (SGs). It is found that, usage of ST not only manages line flow congestion and maintains bus voltage, but also increases overall efficiency.

Steady state power system insecurity such as transmission lines being overloaded causes transmission elements cascade outages which may lead to complete blackout. The power system operator must know the system state at any instant. The contingency analysis is used to predict which contingencies make system violations and rank the contingencies according to their relative severity. Contingency Analysis is useful both in the network design stages and for programmed maintenance or network expansion works to detect network weaknesses. The weaknesses can be strengthened by transmission capacity increase, transformers rating increase besides circuit breakers ratings increase. This work outlines mathematical models for the simulation of generator outages and transmission line and transformer outages so as to carry out a full AC load flow based contingency analysis and ranking. The method has been applied to Sudan National Grid (NG) and gives good results in determining the network weakness...

Steady state power system insecurity such as transmission lines being overloaded causes
transmission elements cascade outages which may lead to complete blackout. The power system
operator must know the system state at any instant. The contingency analysis is used to predict
which contingencies make system violations and rank the contingencies according to their
relative severity. Contingency Analysis is useful both in the network design stages and for
programmed maintenance or network expansion works to detect network weaknesses. The
weaknesses can be strengthened by transmission capacity increase, transformers rating increase
besides circuit breakers ratings increase. This work outlines mathematical models for the
simulation of generator outages and transmission line and transformer outages so as to carry out
a full AC load flow based contingency analysis and ranking. The method has been applied to
Sudan National Grid (NG) and gives good results in determining the network weaknesses and
suggesting the new transmission lines and transformers capacities which ensures better power
system security.

The power quality problems in power utility distribution systems are not new, but recently
their effects have gained public awareness. Advances in semiconductor device technology have
fuelled a revolution in electronics and power electronics over the past decade, many factories
and heavy loads which are recently installed highly affect power quality due to their nonsinusoidal
current. In this paper different harmonics sources such as electric ballast, magnetic
ballast, vapor mercury, halogen spot light and halogen with dimmer and their effects and two
methods of harmonics elimination are studied. The results obtained show that at incidence of
harmonics the currents waveform are not sinusoidal, THD values are out of limits, there is a set
of high order harmonics, the current values are higher and power factor is lower. However, the
results obtained when the harmonics are eliminated show that THD values are reduced, the
currents values are reduced, the power factor is improved and values of current harmonics
orders are reduced.