Risk-based security assessment and effects of fluctuating in-feed on risk

In many power systems, fluctuating in-feed contributes a big share of total energy produced. This means new challenges to operate the system securely. In this paper, a risk-based method for security assessment of power systems is presented. The method takes the probability and severity of contingencies into account. The method proposed considers also the forecast errors of fluctuating in-feed and is therefore applicable in operational planning. Because the method proposed takes the uncertainty of in-feed into account, possible cascades triggered by fluctuations may be identified in operational planning. This information may be used in planning of remedial actions. The method has been illustrated using the IEEE RTS-96 test system.