Large-scale unit commitment under uncertainty: an updated literature survey

The Unit Commitment problem in energy management aims at finding the optimal production schedule of a set of generation units, while meeting various system-wide constraints. It has always been a large-scale, non-convex, difficult problem, especially in view of the fact that, due to operational requirements, it has to be solved in an unreasonably small time for its size. Recently, growing renewable energy shares have strongly increased the level of uncertainty in the system, making the (ideal) Unit Commitment model a large-scale, non-convex and uncertain (stochastic, robust, chance-constrained) program. We provide a survey of the literature on methods for the Uncertain Unit Commitment problem, in all its variants. We start with a review of the main contributions on solution methods for the deterministic versions of the problem, focussing on those based on mathematical programming techniques that are more relevant for the uncertain versions of the problem. We then present and categorize the approaches to the latter, while providing entry points to the relevant literature on optimization under uncertainty. This is an updated version of the paper "Large-scale Unit Commitment under uncertainty: a literature survey" that appeared in 4OR 13(2), 115--171 (2015); this version has over 170 more citations, most of which appeared in the last three years, proving how fast the literature on uncertain Unit Commitment evolves, and therefore the interest in this subject

Metaheuristics for Transmission Network Expansion Planning

This chapter presents the characteristics of the metaheuristic algorithms used to solve the transmission network expansion planning (TNEP) problem. The algorithms used to handle single or multiple objectives are discussed on the basis of selected literature contributions. Besides the main objective given by the costs of the transmission system infrastructure, various other objectives are taken into account, representing generation, demand, reliability and environmental aspects. In the single-objective case, many metaheuristics have been proposed, in general without making strong comparisons with other solution methods and without providing superior results with respect to classical mathematical programming. In the multi-objective case, there is a better convenience of using metaheuristics able to handle conflicting objectives, in particular with a Pareto front-based approach. In all cases, improvements are still expected in the definition of benchmark functions, benchmark networks and robust comparison criteria

Gamma heavy chain disease: clinical aspects and characterization of a deleted, noncovalently linked gamma1 heavy chain dimer (BAZ)

This report describes the clinical and immunoglobulin features of a patient with gamma heavy chain disease (HCD), who presented with a clinical picture suggestive of an underlying malignancy rather than the usual picture of lymphoma or granulomatous disease. A unique clinical feature was the nearly total replacement of the submaxillary glands by plasma cells. The patient's serum and urine contained a paraprotein, gammaHCD protein BAZ, which belongs to the gamma1 subclass and forms noncovalently linked dimers with a molecular weight of approximately 60,000 daltons. This mutant protein exhibited a deletion which encompassed most of the variable (V) region, the first constant domain (CH 1), and the hinge region. In addition, preliminary structural analyses demonstrated the replacement of alanine by glycine in position 431 of the carboxyterminal octadecapeptide. This substitution may possibly represent another allotypic marker on IgG1 proteins.</jats:p

Gamma heavy chain disease: clinical aspects and characterization of a deleted, noncovalently linked gamma1 heavy chain dimer (BAZ)

Abstract This report describes the clinical and immunoglobulin features of a patient with gamma heavy chain disease (HCD), who presented with a clinical picture suggestive of an underlying malignancy rather than the usual picture of lymphoma or granulomatous disease. A unique clinical feature was the nearly total replacement of the submaxillary glands by plasma cells. The patient's serum and urine contained a paraprotein, gammaHCD protein BAZ, which belongs to the gamma1 subclass and forms noncovalently linked dimers with a molecular weight of approximately 60,000 daltons. This mutant protein exhibited a deletion which encompassed most of the variable (V) region, the first constant domain (CH 1), and the hinge region. In addition, preliminary structural analyses demonstrated the replacement of alanine by glycine in position 431 of the carboxyterminal octadecapeptide. This substitution may possibly represent another allotypic marker on IgG1 proteins.</jats:p

A Real Test System For Power System Planning, Operation, and Reliability

Made available in DSpace on 2018-11-26T17:48:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-04-01Nowadays, several test systems available in the specialized literature are used to verify studies regarding power system planning or network reliability. However, there are no test systems currently available with enough information in order to endorse studies that simultaneously approach expansion planning, operation, and reliability issues. This paper introduces a real test system, including the load modeling, and generation and transmission systems. The main objective is to provide all the details and information required to evaluate methods and models developed for power system planning, operation, and reliability. The presented load modeling includes hourly, daily, weekly, monthly, and seasonal patterns. Furthermore, besides the substation data, reliability details, construction costs, and characteristics of right of ways (e.g., line length, impedance, and ratings) for the transmission system are exposed. The real transmission system presented contains 39 buses, 135 transformers, and 66 lines at two voltage levels: 230 and 400 kV. Finally, the generation system reliability data as well as operation and installation costs for each unit are also provided.Sao Paulo State Univ, Fac Engn Ilha Solteira Campus, Dept Elect Engn, Ilha Solteira, SP, BrazilShahid Beheshti Univ, Dept Elect Engn, Tehran, IranUniv Tehran, Sch Elect & Comp Engn, Coll Engn, Tehran, IranSao Paulo State Univ, Fac Engn Ilha Solteira Campus, Dept Elect Engn, Ilha Solteira, SP, Brazi

A Search Space Reduction Strategy and a Mathematical Model for Multistage Transmission Expansion Planning with N−1N-1 N - 1 Security Constrains

This paper proposes a linear disjunctive model to solve a multistage transmission expansion planning problem (MTEP) considering N - 1 security constraints. The use of a disjunctive linear model guarantees finding the optimum solution of the problems using existing classical optimization methods. For large-scale systems, when finding the optimum or even high-quality solutions of the MTEP problem is not possible in polynomial time, a search space reduction methodology (SSRM) is proposed. By using SSRM, it is possible to obtain very high-quality solutions or in most cases the optimum solution of the MTEP problem. The N - 1 security constraint indicates that the transmission system must be expanded in such a way that, despite the outage of a system line (a pre-defined set of contingencies), the system continues to operate properly. The model was implemented using a modelling language for mathematical programming (AMPL) and solved using the CPLEX, which is a commercial solver. The IEEE 24-bus, Colombian 93-bus, and Bolivian 57-bus systems are used to evaluate and show the performance of the proposed mathematical model and the search space reduction strategy