• Journal of Electrical Engineering and Technology
• /
• v.4 no.4
• /
• pp.451-456
• /
• 2009

Through the development of phasor measurement units (PMU), various aspects of power system dynamic behavior could be monitored and diagnosed. Monitoring dynamic voltage stability has become one of the achievements we can obtain from PMUs. It is very important to select the most appropriate method for the Korea Electric Power Corporation (KEPCO) system since there are many voltage stability indices. In this paper, we propose an advanced WAVI (Wide Area Voltage Stability) that is well suited for the purposes of monitoring the dynamic voltage stability of KEPCO's PMU installation plan. The salient features of the proposed index are: i) it uses only PMU measurements without coupling with EMS data; ii) it is computationally unburdened and can be applied to real-time situations. The proposed index is applied to the KEPCO test system and the results show that it successfully predicts voltage instability through comparative studies.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.12
• /
• pp.2328-2334
• /
• 2009

Through the development of phasor measurement units (PMU), various aspects of power system dynamic behavior could be monitored and diagnosed. Monitoring dynamic voltage stability becomes one of achievements we can obtain from PMUs. It is very important to select the method appropriate to the KEPCO system since there are many voltage stability indices. In the paper, we propose an advanced WAVI (Wide Area Voltage Stability) for monitoring dynamic voltage stability. It reflects the PMU installation plan of KEPCO, thus it is suitable for KEPCO system specially. The salient features of the proposed index are; i) it uses only PMU measurements without coupling with EMS data. ii) it is computationally unburden so that it can be applied to real-time situation. The proposed index is applied to the KEPCO test system and the result shows that it successfully predicts voltage instability through the comparative studies.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.9
• /
• pp.1530-1539
• /
• 2010

Recent technology advancement related to computer & communication and measuring devices allows system operators to adopt more intelligent monitoring and control systems to their power systems in order to prevent massive system blackout. Among them, wide-area monitoring and control(WAMAC) system based on synchro-phasor technology has been widely applied to power systems for their own purposes. In this paper, the study on the development of load shedding scheme to improve voltage stability in KEPCO system is introduced. Summary of WAMAC technology being developed and applied in the world through extensive literature survey is proposed. And methodology to develop voltage stability index and multi-step load shedding scheme based on synchro-phasor data is also presented.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.63 no.1
• /
• pp.1-6
• /
• 2014

An electric power system sometimes fails because of disturbances that occur unexpectedly, such as the uncontrolled loss of load that developed from cascading blackout. Which make stability through a little of under voltage load shedding should work. The development of phasor measurement unit(PMU) makes network supervision possible. The information obtained from PMU is synchronized by global positioning system(GPS). There are many real-time algorithms which are monitoring the voltage stability. This paper presents the study on the VILS(Voltage Instability Load Shedding) using PMU data. This algorithm computes Voltage Stability Margin Index(VSMI) continuously to track the voltage stability margin at local bus level. The VSMI is expressed as active and reactive power. The VSMI is used as an criterion for load shedding. In order to examine the algorithm is effective, applied to KEPCO system.