Computation of Worst Operation Scenarios Under Uncertainty for Static Security Management

Abstract

Abstract-This paper deals with day-ahead static security assessment with respect to a postulated set of contingencies while taking into account uncertainties about the next day system conditions. We propose a heuristic approach to compute the worst-case under operation uncertainty for a contingency with respect to overloads. We formulate this problem as a non-convex nonlinear bilevel program that we solve approximately by a heuristic approach which relies on the solution of successive optimal power flow (OPF) and security-constrained optimal power flow (SCOPF) problems of a special type. The method aims at revealing those combinations of uncertainties and contingencies for which the best combination of preventive and corrective actions would not suffice to ensure security. Extensive numerical results on a small, a medium, and a very large system prove the interest of the approach.Index Terms-Bilevel programming, operation under uncertainty, optimal power flow, security-constrained optimal power flow, worst-case analysis. NOMENCLATUREIn the paper vectors are written using bold characters. A. SetsSet of power flow equations in pre-contingency state. Set of power flow equations after contingency .Set of operating limits in pre-contingency state.Set of operating limits after contingency .Set of postulated contingencies.Set of violated constraints.Set of problematic constraints.Union of all sets of problematic constraints.Set of problematic patterns.

A robust convex optimization framework for autonomous network planning under load uncertainty

“…In this paper, we present a robust approach to autonomous microgrid planning considering load consumption uncertainty. This paper extends our previous work on a deterministic formulation for this problem [3] with the computation of worst operating scenarios developed in [4]. This paper is organized as follows: the deterministic formulation previously developed is presented in section II, section III describes the uncertainty model that is used and section IV presents the approach used to compute problematic operating scenarios.…”

“…Finally, as proposed in [4], we introduce lower and upper bounds on voltage angle differences even if this formulation doesn't include angles explicitly. As a matter of fact, these constraints significantly tighten the model.…”

“…Nonetheless, even in the simple case where Ω is a rectangular set, the amount of vertices is equal to 2 n Ω which rapidly becomes intractable with a growing n Ω . Consequently, we adopt the approach developed in [4] which has been used for security planning under uncertainty in transmission networks [8]. This approach consists in computing a subset of the vertices of Ω, i.e.…”

Adjustable risk-based direct current optimal power flow

“…In , the worst‐case operating conditions of a power system under operational uncertainty have been studied in the framework of robust unit commitment problems, which seek for commitment and dispatch of generation resources for immunizing against all possible uncertainty situations. In , a heuristic approach to compute the worst‐case realization of uncertain nodal net injection for a contingency with respect to overloads was proposed.…”

The value of using chance-constrained optimal power flows for generation re-dispatch under uncertainty with detailed security constraints

“…Choosing more values from the possible range of the uncertain parameters enables the operator to better prepare the system as more of the uncertainty is considered [13], [14], but it also entails longer computation time. The shorter the considered time horizon the stronger the requirements on short computation times are.…”