Rule-based procedure for automatic selection of contingencies in evaluation of dynamic security of a power distribution system

A method for selecting fault contingencies to be evaluated in a real-time determination of their effects upon the dynamic security of a power system that includes power generators and power-carrying lines, the method comprising the following steps:

• (a) defining a full set of potential contingencies for said power system;
• and
• (b) using a computer system to apply a rule set including at least one interface rule to said full set to determine at least one sub-set thereof, said subset identifying contingencies that are potentially unstable to said power system;
• wherein said interface rule governs a cut-set defined by the following steps:
• (c) representing said power system as a collection of network nodes having inter-node connections represented as interconnecting arcs, wherein said network nodes are spatially identified such that power flow of said power system in any said arc goes from a first direction toward a second direction;
• (d) defining a said cut-set as a set of said interconnecting arcs that when removed from a connected said network separates said network into at least two second unconnected parts;
• (e) defining from a set of each said cut-set a minimal cut-set, wherein a said minimal cut-set is a cutset such that a subset set of said minimal cut-set arcs is not itself a cutset;
• and
• (f) arriving at a minimal cut-set that is not a subset of another cut-set.