arXiv subjects

Matthias Silbernagl

Publications and source records attributed to Matthias Silbernagl.

3 recordsLinked to original sources

arXiv2015

Improving Accuracy and Efficiency of Start-up Cost Formulations in MIP Unit Commitment by Modeling Power Plant Temperatures

This paper presents an improved mixed-integer model for the Thermal Unit Commitment Problem. By introducing new variables for the temperature of each thermal unit, the off-time-dependent start-up costs are modeled accurately and with a lower integrality gap than state-of-the-art formulations. This new approach significantly improves computational efficiency compared to existing formulations, even if they only model a rough approximation of the start-up costs. Our findings were validated on real-world test cases using CPLEX.

math.OC↗

arXiv2015

The Summed Start-up Costs in a Unit Commitment Problem

We consider the sum of the incurred start-up costs of a single unit in a Unit Commitment problem. Our major result is a correspondence between the facets of its epigraph and some binary trees for concave start-up cost functions CU, which is bijective if CU is strictly concave. We derive an exponential H-representation of this epigraph, and provide an exact linear separation algorithm. These results significantly reduce the integrality gap of the Mixed Integer formulation of a Unit Commitment Problem compared to current literature.

math.OC↗

arXiv2014

Implementing a Unit Commitment Power Market Model in FICO Xpress-Mosel

Starting from a basic Unit Commitment problem as published in [Carrión2006], we develop a fully functional, running implementation for Xpress Mosel, useable in power market modeling. The constraints of the model are discussed in details and solutions to left open implementation problems are presented, guidelines on how to handle data input (from both, databases and Excel), as well as data output (to Excel) are given.

math.OC↗