Impact assessment of voltage swell in transmission system

Abstract

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 system's 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.