The Determination of Fair Assigned Security Price for a Given Market Participant in Deregulated Power System

Regulated power systems not only were built with excess capacity, but also operated with conservative security limits. But under deregulated environment, the requirement of maintaining security and maximizing the return on existing investments becomes one typical antinomy, resulting in operating the system closer to the traditional deterministic limits or even beyond them by assuming that the contingencies may not actually occur. This fact requires more refined methods for power system security proper assessment and fair distribution that account for the probabilistic nature of uncertain variables in the decision-making environment. This paper presents a framework of fair assigned security price for a given market participant which firstly contains two comprehensive pricing methods for quantifying the transmission security cost based on risk analysis and voltage stability constrained OPF market models for comparison. In the later method, this paper next distributes the security cost equitably to all participants based on the impact of their transactions on the ATC, which is calculated by using continuation power flow (CPF) or OPF approaches and should consider thermal, voltage and stability limits with N-1 contingency criteria. The nodal security price can be attained finally. All above-mentioned approaches are illustrated by evaluating the results of an experiment that simulates a full AC network with 6 buses, three of which are generators.