Publications de Konstantina Christakou

Voltage Control in Active Distribution Networks Under Uncertainty in the System Model: A Robust Optimization Approach

Mario Paolone, Konstantina Christakou, Ali Abur

Within the context of ancillary services for Active Distribution Networks (ADNs), application of intelligent control techniques is required in order to achieve specific operation objectives. Despite their differences, most control mechanisms proposed in th ...

2018

Concurrent Voltage Control and Dispatch of Active Distribution Networks by means of Smart Transformer and Storage

Mario Paolone, Konstantina Christakou, Fabrizio Sossan, Xiang Gao

Dispatching active distribution networks is expected to play an important role in the smart grid technologies. Voltage control is also starting to be widely proposed to avoid voltage violations in the electrical grid. The integration of the storage in the ...

2018

Fair control of distributed PV plants in low voltage grids

Jean-Yves Le Boudec, Mario Paolone, Konstantina Christakou

In this paper we evaluate the potential of distributed photovoltaic (PV) plants for providing primary voltage control to the local distribution grid. Compared to the existing literature, we design an algorithm that schedules the nodal active and reactive p ...

IEEE2017

AC OPF in radial distribution networks – Part II: An augmented Lagrangian-based OPF algorithm, distributable via primal decomposition

Jean-Yves Le Boudec, Mario Paolone, Dan-Cristian Tomozei, Konstantina Christakou

In the first part of this two-part paper we show that the branch-flow convexification of the OPF problem is not exact and that the ADMM-based decomposition of the OPF fails to converge in specific scenarios. Therefore, there is a need to develop algorithms ...

Elsevier2017

AC OPF in radial distribution networks – Part I: On the limits of the branch flow convexification and the alternating direction method of multipliers

Jean-Yves Le Boudec, Mario Paolone, Dan-Cristian Tomozei, Konstantina Christakou

The optimal power-flow problem (OPF) has always played a key role in the planning and operation of power systems. Due to the non-linear nature of the AC power-flow equations, the OPF problem is known to be non-convex, therefore hard to solve. During the la ...

Elsevier2017

Enhancing the Provision of Ancillary Services from Storage Systems using Smart Transformer and Smart Meters

Mario Paolone, Konstantina Christakou, Fabrizio Sossan, Xiang Gao

The Smart Transformer, a solid-state transformer with control and communication functionalities, can be the ideal solution for integrating storage into the grid. By leveraging the knowledge of the grid state of distribution grids thanks to smart meters and ...

IEEE2017

A unified control strategy for active distribution networks via demand response and distributed energy storage systems

Konstantina Christakou

As part of the transition to a future power grid, distribution systems are undergoing profound changes evolving into Active Distribution Networks (ADNs). The presence of dispersed generation, local storage systems and responsive loads in these systems incu ...

Elsevier Science Bv2016

Hardware-in-the-loop Validation of the Grid Explicit Congestion Notification Mechanism for Primary Voltage Control in Active Distribution Networks

Jean-Yves Le Boudec, Mario Paolone, Konstantina Christakou, Styliani Sarri, Marco Pignati, Roman Rudnik

The Grid Explicit Congestion Notification control mechanism (GECN) is a broadcast-based real-time demand- response mechanism designed for primary voltage control in Active Distribution Networks (ADNs) [1,2]. An extensive set of off-line simulations has ind ...

Università degli Studi di Genova, Italy2016

Model-less Measurement-based Computation of Voltage Sensitivities in Unbalanced Electrical Distribution Networks

Mario Paolone, Konstantina Christakou, Carl Emile Mugnier, Mauro Carpita

Within the context of microgrids optimal voltage control, most schemes proposed in the literature either rely on (i) droop-control methods or (ii) methods involving the computation of explicit nodal power set-points as a solution to a given optimization pr ...

Università degli Studi di Genova, Italy2016

Real-Time Optimal Controls for Active Distribution Networks : From Concepts to Applications

Konstantina Christakou

Decentralized generation, distributed energy storage systems and active participation of end-users in the lower level of the electrical infrastructure, intelligently managed to provide grid support, define the notion of Active Distribution Networks (ADNs). ...

EPFL2015

Primary Voltage Control in Active Distribution Networks via Broadcast Signals: The Case of Distributed Storage

Jean-Yves Le Boudec, Mario Paolone, Dan-Cristian Tomozei, Konstantina Christakou, Maryam Bahramipanah

In this paper, we consider an active distribution network (ADN) that performs primary voltage control using real-time demand response via a broadcast low-rate communication signal. The ADN also owns distributed electrical energy storage. We show that it is ...

Ieee-Inst Electrical Electronics Engineers Inc2014

GECN: Primary Voltage Control for Active Distribution Networks via Real-Time Demand-Response

Jean-Yves Le Boudec, Mario Paolone, Dan-Cristian Tomozei, Konstantina Christakou

Demand response (DR) has traditionally targeted peak shaving for the optimal allocation of electricity consumption on a time scale that ranges from minutes to hours. However, with the availability of advanced monitoring and communication infrastructure, th ...

Ieee-Inst Electrical Electronics Engineers Inc2014

Integrated voltage control and line congestion management in Active Distribution Networks by means of smart transformers

Mario Paolone, Konstantina Christakou, Giovanni De Carne

Within the context of Active Distribution Networks (ADNs), smart transformers represent very powerful devices able to provide fast and efficient control actions with respect to different ADNs ancillary services. This paper discusses the benefits, in terms ...

IEEE Industrial Electronics Society2014

Efficient Computation of Sensitivity Coefficients of Node Voltages and Line Currents in Unbalanced Radial Electrical Distribution Networks

Jean-Yves Le Boudec, Mario Paolone, Dan-Cristian Tomozei, Konstantina Christakou

The problem of optimal control of power distribution systems is becoming increasingly compelling due to the progressive penetration of distributed energy resources in this specific layer of the electrical infrastructure. Distribution systems are, indeed, e ...

Ieee-Inst Electrical Electronics Engineers Inc2013