Preventive/corrective control for voltage stability using direct interior point method

This paper describes the applications of the interior point (IP) method on preventive/corrective control (PCC) for voltage stability. The mathematical model of preventive/corrective control, based on the control costs, is proposed. In the real time mode, the preventive control is carried out when the voltage stability margins between the operating point and the stability boundary are too small. In the study mode, the corrective control is carried out when the voltage is insecure. After preventive/corrective control, not only should the system operation point be in the voltage secure area, but some voltage stability margins should also be maintained. The approach proposed has been successfully tested on five systems-from 100 bus system to 4000 bus system.