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.

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