A DIRECT METHOD FOR SECURITY-CONSTRAINED UNIT COMMITMENT

Secure operation is an enduring concern to electric utilities. Several factors oblige utilities to operate their systems-particularly transmission systems-at or close to their capacities. Few methods for scheduling electric generating units, however, take security into account. Utilities, therefore, may inadvertently risk overloading critical transmission lines if units are not rescheduled. Without advance planning a utility may incur significant costs if it must reschedule generation retroactively. This paper presents a practical method to account for security constraints when scheduling electric generating units. Our results indicate that this method obtains lower-cost solutions faster than if the security constraints are considered retroactively.