A study on the effects of BTB HVDC for fault current reduction applied metropolitan area in KEPCO Grid

The South Korean Power System is characterized by a large percentage of its loads, approximately 43%, being concentrated in the Seoul area, in the northwestern part of the country(metropolitan area), while the largest percentage of the generation is located in the southern part of the country. As such, most of the power typically flows from the southern areas of the grid to the northwestern area. This means long distance power transfer which has the potential to result in voltage instability problems. Therefore, when that area has transmission fault, huge fault current occurs. This problems have been solved by deploying BTB(Back To Back) HVDC. BTB HVDC can divide into two or three systems and control power flow. If BTB is installed at metropolitan area, there are many advantages. Electric power can flow between systems by BTB HVDC. And BTB HVDC can prevent from blackout of the wide area by blocking the spread of the faults. This report shows the effects of BTB HVDC for fault current reduction applied metropolitan area in KEPCO Grid.