This research presents the studying of short circuit in distribution system that affect to critical equipment voltage sag and overvoltage while short circuit event. Lead into the quality of electric user. Effect on economics damaged Distribution system voltage level 22kV of The Provincial Electricity Authority. It is the analysis model by computer program. The event of short circuit set in a many distribution systems. The analysis result Magnitude of voltage while short circuit bring to assessment voltage sag and overvoltage from average voltage of the repeat event. Then set boundary of voltage at load point in a many. The experiment shows the problem of the quality of electric be affect to critical equipment less than load point close connection with substation.

This Thesis presents an analysis of wind turbines in a power distribution system that has a wind power source. By comparing the wind turbine with 3 blades and 4 wind turbines while there is no distribution in the distribution system. And the load is distributed in the distribution system To analyze the differences of these 2 wind turbines analyze the pressure values The power quality in the distribution system that occurs. And able to apply wind turbine energy for sustainability And practices to support the correct power supply In the distribution system and able to provide electricity with efficiency and reliability Wind turbine when connecting to the electricity distribution system There is a significant impact on the power distribution system such as the impact on the power loss. Pressure impact etc. It can be seen that the wind turbine with 3 blades works less than the wind turbine with 4 blades not so much. Therefore the test shows that the analysis of the electricity quality in this distribution system for use as a case study And continue to improve the production of wind turbines in the electricity distribution system.

This paper presents an efficient algorithm for optimization of radial distribution systems by a feeder reconfiguration to balance feeder loads and eliminate overload conditions. The system load-balancing index is used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal feeder reconfiguration of load balancing. A method based on Tabu search algorithm The Tabu search algorithm is employed to search for the optimal feeder reconfiguration. Simulation results for a radial 69-bus system with reconfiguration and capacitors placement. The study results show that the distribution system with capacitor placement and optimal on/off patterns of the switches feeders reconfiguration can be load balancing in distribution systems.

This research presents an Analysis of Voltage Sags on the Installation of Distributed Generation in the Distribution 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 Line 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.

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.