Impact of Wind Generation on Risk-based Security Assessment of Power System

Abstract

The electric power system is one of the largest and most intricate infrastructures. Therefore, it is critical to assess and maintain its security. A power system security assessment is indispensable for identifying post-contingency issues, taking corrective measures, and protecting the system from blackouts. This paper examined the impact of wind generation on the risk-based security assessment of a power transmission network in the context of planning. DIgSILENT PowerFactory software was used to conduct the analysis using a combination of the brute force technique and the nonsequential Monte Carlo (MC) simulation method on the IEEE 39-bus transmission test system. Optimal power flow (OPF) was used to quantify security, considering (N-1), (N-2), and (N-3) line outages and an (N-1) bus outage. Moreover, the average cost deviation from the mean optimal system operating cost was proposed as a novel security indicator. The results obtianed accurately depicted the effects of changing wind generation levels on system security in terms of risk. The most and least critical line(s) and bus in the system, for different wind generation levels, were also determined. Moreover, the worst-case wind-generation threshold level using two different cost functions for wind was identified.