Most of Metropolitan Electricity Authority (MEA) electric power system is using overhead line. It is 94% in the system including subtransmission distribution and low voltage system. All of them were installed on concrete pole. At present many public facilities have been built such as Sky-Train. It causes more constrains for construction with concrete pole due to lack of right of way. MEA needs to using electrical monopole plays an important role. It’s easier than concrete pole for construction and it requires less construction area than concrete pole. This research evaluation of The Reduce Effect of Lightning on Transmission Line. Case lightning strike on overhead ground wire (OHGW) at pole top of electrical monopole with suspension insulator Focusing on three factors is pole top voltage critical current and back flashover rate (BFOR). ATP-EMTP software is used for simulation. The results show that BFOR is reduced by 79% on electrical monopole structure with suspension insulator compared with existing concrete pole. BFOR is also reduced by 33.17% on concrete pole with external ground wire. The results could be served as a guideline in subtransmission line design and improvement in MEA power system.

This thesis presents an assessment of voltage sags when faults are happened in the 115 kV transmission line of the Provincial Electricity Authority (PEA) when distributed generation (DG) is installed in the system. The computer program PSCAD/EMTDC (Power Systems Computer Aided Design / Electromagnetic Transient in DC system) version 4.2 is applied to provide electrical parameters for the modeling and simulation and to analyze the fault occurred which resulted in voltage sag. Test results from PSCAD/EMTDC show the values of voltage sag when 5 types of fault are occurred (Single Line to Ground Fault Double Line to Ground Fault Three Phase to Ground Fault Line to Fault and Three Phase Fault). For all cases the value of root mean square voltage before fault is 100% or 1.0 pu. It can be seen that for both radial line and closed circuit when DG are installed in the system the value of phase to ground RMS residual voltage and phase to phase RMS residual voltage at the bus of Bang-pa-in 2 substation are more than the values in case of the system without DG.

This Research purposes assessment of lightning performance on transmission system 69 kV in Metropolitan Electricity Authority (MEA). The case studies illustrated the lightning strike to direct top pole in order to guideline considering the critical flashover voltage value of insulator is able to withstand it and improvement lighting protection in the future. This solution analyzes using the Alternative Transient Program-Electromagnetic Transient Program (ATP-EMTP). The result found that voltage across insulator before and after improvement lightning protection by external ground wire. Factor effect to voltage across the insulators is the tower footing resistance wave of lightning current and interval between towers. It depends on relation with front time of wave. The analysis economics is very important. This Research is studying interruption cost of outage since back flashover so analysis the break even point of the installation external ground. The result found upon improvement lightning protection by installed external ground. The pay back period of that is 9 years installed ago. This result can conclusion is external ground able reduction interruption costs of outage.

This paper presents a study of low-frequency oscillations in compensated electric power systems with Flexible AC Transmission System of the power system frequency using PSAT Tool box To assist in the analysis of the stability of the system When the power transients in power systems is simulated By using standard IEEE 14 bus system as a case study. The Equipment that used to control the swing frequency of the is a flexible electrical power control devices or FACTS are two kinds of serial and parallel. The analysis showed that two models are compared with the time (Time Domain) and see the effect of the Eigen (Eigen Value) of the simulation results show work to see that controls are electrical flexible compensation. of low frequency oscillations in power systems in acceptable coordinates

This paper presents the method to solve the transmission line parameters calculation problem with computer program. The transmission line parameters are an important of power system which calculates the voltage current power and other. Transmission line parameters program is programmed with Delphi in graphical user interface. This program can calculated the resistance inductance and capacitance of single and three phase transmission line. To verify the performance of the proposed program the results are compared with the manual method. The results show that the program method is able to obtained 100 percent accuracy