Application of Distributed Optimal Power Flow to Power System Security Assessment

Abstract

This paper presents an algorithm for the parallel solution of the security constrained optimal power flow (SCOPF) problem in a decentralized framework, consisting of regions, using a price-based mechanism that models each region as an economic unit. We first solve the distributed optimal power flow (OPF) problem to determine the maximum secure simultaneous transfer capability of each tie-line between adjacent regions by taking into account only the security constraints imposed on the tie-lines. In this article, the line outage distribution factors (LODF) calculated at the current state are used to formulate the appended constraints. Once the secure transfer capability of each tie-line is determined, the intraregional SCOPF is performed using the conventional linear programming (LP) approach. A description of the inclusion of security constraints with the distributed optimal power flow algorithm will be given, followed by the case studies for Korea Electric Power System.

Security Constraint Optimal Power Flow (SCOPF) A Comprehensive Survey

“…Authors have implemented this algorithm for an IEEE 3 area RTS-96 and Balkan Power system consisting of 310 buses, 77 units, 485 internal lines and 5 tie-lines. Don Hur et al [51] presented a new parallel decentralized solution for SCOPF problem using Linear Programming using Line Outage Distribution Factor and was implemented on the Korean Power System consisting of four regions and each region connected directly by the major eight 345 kV transmission lines and seventeen 154 kV transmission lines, which are considered as tie lines. The intraregional SCOPF is solved using conventional Linear Programming (LP) approach by the authors.…”

Available Transfer Capability Calculation

“…Optimal power flow with transient stability constraints was proposed by (Tuglie, Dicorato, Scala, & Scarpellini, 2000;Chen, Tada, & Okamoto, 2001) where the differential equations are used to define the domain. The security constrained OPF method (Hur, Park, K, & Kim, 2003;Shaaban M. , Li, Yan, Ni, & Wu, 2003;Gao, Zhou, M, & Li, 2006), has also been used to solve the Steady-State Security Constrained (SSSC) ATC problem. However, the correct representation of security constraints (and even more so if post-contingency actions are to be taken into account) may cause a great increase of orders of magnitudes in problem size.…”

Total transfer capability computation using small signal stability-based security constrained optimal power flow

“…In References [2,3], a security constrained optimal power flow (SCOPF) has been used to solve the steady-state security constrained total transfer capability (TTC) problem. Since the inclusion of contingency constraints is the foremost challenge, it is expected that eventually contingency constrained optimal power flow (CCOPF) is becoming a standard tool in the industry [4].…”