Received December 19, 2017, accepted January 31, 2018. Date of publication xxxx 00, 0000, date of current version xxxx 00, 0000. Digital Object Identifier 10.1109/ACCESS.2018.2805330 Ancillary Services 4.0: A Top-to-Bottom Control-Based Approach for Solving Ancillary Services Problems in Smart Grids GIULIA DE ZOTTI 1, S. ALI POURMOUSAVI2, (Member, IEEE), HENRIK MADSEN1, (Senior Member, IEEE), AND NIELS KJØLSTAD POULSEN1, (Senior Member, IEEE) 1Institut for Matematik og Computer Science, Danmarks Tekniske Universitet, 2800 Kongens Lyngby, Denmark 2Global Change Institute, The University of Queensland, Brisbane, QLD 4072, Australia Corresponding author: Giulia De Zotti (
[email protected]) This work was supported in part by CITIES project under Grant DSF-1305-0027B and in part by the European Union's Horizon 2020 Smart-Net project under Grant 691405. ABSTRACT Power systems are experiencing a large amount of renewable generation with highly stochastic and partly unpredictable characteristics. This change in energy production implies significant consequences related to the provision of ancillary services (AS). Current markets dedicated to the provision of AS are not able to benefit from the flexible energy resources. They also cannot cope with the new level of stochasticity, non-linearity, and dynamics of generation and flexibility. To overcome such issues and exploit the potential of flexibility resources, a new strategy is required. In this paper, by capitalizing on flexibility resources' potential, AS 4.0 approach is proposed, which offers a comprehensive solution for the AS provision in the smart grid era. INDEX TERMS Ancillary services 4.0, flexible retail electricity price, smart grid, power system operation, peer-to-peer, control-based approach.