The analysis of the grounding system overvoltage in High voltage substation will be held at Bumnetnarong substation Electricity Generating Authority of Thailand ( EGAT ) by using ATP draw for grounding system’s model of substation also to model overvoltage from lightning and to read the result of overvoltage from differences positions. The advantages of the experiment are to be educated and to who design Grounding system in high voltage substation EGAT. The Study’s result of the over voltage level on Ground Potential Rise: GPR model shows that the pie will show close result to the result from the calculation by standard IEEE Std 80-2000 and the result of the Fault Current at the middle position of the grounding system will result in higher overvoltage than at the result at the corner position of Grounding system. The result of Ground Resistance: Rg shows that the increasing of overvoltage the increasing of Ground Resistance: Rg

Electricity Generating Authority of Thailand (EGAT) encountered problems voltage swell from the changes of power system configuration high-voltage 115 kV substation name Lopburi2 to radial. Control Center closed capacitor bank caused the steel industry electric power plants and renewable energy solar tripped themselves out. As a result EGAT loosed of power produced of solar power plants. It also affected confidence in the systems power consumption. EGAT’s necessary to learn from this event. This research was simulation power system modeling of “High Voltage Substation Lopburi2” and grid connection both the system EGAT and PEA with EMTDC-PSCAD for analysis of the voltage swell caused by close capacitor bank at “Lopburi2” substation compared with actual events then calculated the voltage swell occurred at high voltage station linkage. Finally this research presents a method of reduction of their impact of close capacitor bank at “Loburi2” to avoid the voltage swell in the future.

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.

The purpose of this research is to facilitate technology of limiting excess electricity from the source before supplying to the electrical appliances. The distribution of electricity by Metropolitan Electricity Authority (MEA) frequently exceeds the needs of households and factories due to the fact that the voltage has to be enough to send electricity to users who are located further at the end of the voltage grid lines. Most electrical appliances are designed to perform at optimum voltage of 220 Volt. The voltage optimization system controls the incoming voltage to fit the optimum voltage of electrical appliances which will reduce the overheating phenomenon and thus lengthen the lives of electrical appliances. It can save 8-14% of total energy being consumed and potentially reduce CO2 emission. This analysis system can be used for industries in the range of small to large companies. From the development of remote monitoring using a control via internet or 3G/4LTE the voltage optimization system showed practical power saving results of the reduced power usage and lengthen the lives of electrical appliances; that leads to reduction of emerging electricity resource eradication of natural resources increase the chance of marketing competition and energy sustainable