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Safe Bottom-Up Flexibility Provision from Distributed Energy Resources
Authors:
Costas Mylonas,
Emmanouel Varvarigos,
Georgios Tsaousoglou
Abstract:
Modern renewables-based power systems need to tap on the flexibility of Distributed Energy Resources (DERs) connected to distribution networks. It is important, however, that DER owners/users remain in control of their assets, decisions, and objectives. At the same time, the dynamic landscape of DER-penetrated distribution networks calls for agile, data-driven flexibility management frameworks. In…
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Modern renewables-based power systems need to tap on the flexibility of Distributed Energy Resources (DERs) connected to distribution networks. It is important, however, that DER owners/users remain in control of their assets, decisions, and objectives. At the same time, the dynamic landscape of DER-penetrated distribution networks calls for agile, data-driven flexibility management frameworks. In the face of these developments, the Multi-Agent Reinforcement Learning (MARL) paradigm is gaining significant attention, as a distributed and data-driven decision-making policy. This paper addresses the need for bottom-up DER management decisions to account for the distribution network's safety-related constraints. While the related literature on safe MARL typically assumes that network characteristics are available and incorporated into the policy's safety layer, which implies active DSO engagement, this paper ensures that self-organized DER communities are enabled to provide distribution-network-safe flexibility services without relying on the aspirational and problematic requirement of bringing the DSO in the decision-making loop.
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Submitted 29 April, 2025;
originally announced April 2025.
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Stability analysis of nonlinear stochastic flexibility function in smart energy systems
Authors:
Seyed Shahabaldin Tohidi,
Tobias K. S. Ritschel,
Georgios Tsaousoglou,
Uffe Høgsbro Thygesen,
Henrik Madsen
Abstract:
Demand-side management provides a great potential for improving the efficiency and reliability of energy systems. This requires a mechanism to connect the market level and the demand side. The flexibility function is a novel approach that bridges the gap between the markets and the dynamics of physical assets at the lower levels of the energy systems and activates demand-side flexibility with the…
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Demand-side management provides a great potential for improving the efficiency and reliability of energy systems. This requires a mechanism to connect the market level and the demand side. The flexibility function is a novel approach that bridges the gap between the markets and the dynamics of physical assets at the lower levels of the energy systems and activates demand-side flexibility with the purpose of decision-making as well as for offering a new framework for balancing and grid services. Employing this function as a key for many decision-making and control algorithms reveals that a mathematically rigorous stability analysis is required for it. In this paper, we investigate the stability properties of two nonlinear flexibility functions, as a dynamic mapping between electricity price and power consumption. Specifically, we analyze the stability of a deterministic flexibility function and an Itô stochastic flexibility function. Simulation results are also provided to demonstrate the dynamics of the flexibility functions and to show that the analytical results hold.
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Submitted 23 May, 2024;
originally announced May 2024.
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Adaptive flexibility function in smart energy systems: A linearized price-demand mapping approach
Authors:
Seyed Shahabaldin Tohidi,
Henrik Madsen,
Georgios Tsaousoglou,
Tobias K. S. Ritschel
Abstract:
This paper proposes an adaptive mechanism for price signal generation using a piecewise linear approximation of a flexibility function with unknown parameters. In this adaptive approach, the price signal is parameterized and the parameters are changed adaptively such that the output of the flexibility function follows the reference demand signal provided by the involved aggregator. This is guarant…
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This paper proposes an adaptive mechanism for price signal generation using a piecewise linear approximation of a flexibility function with unknown parameters. In this adaptive approach, the price signal is parameterized and the parameters are changed adaptively such that the output of the flexibility function follows the reference demand signal provided by the involved aggregator. This is guaranteed using the Lyapunov stability theorem. The proposed method does not require an estimation algorithm for unknown parameters, that eliminates the need for persistency of excitation of signals, and consequently, simplifies offering the flexibility services. Furthermore, boundedness of the price signal is ensured using a projection algorithm in the adaptive system. We present simulation results that demonstrate the price generation results using the proposed approaches.
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Submitted 15 February, 2024; v1 submitted 6 December, 2023;
originally announced December 2023.
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Near-optimal demand side management in retail electricity markets with coupling constraints via indirect mechanism design
Authors:
Georgios Tsaousoglou,
Konstantinos Steriotis,
Nikolaos Efthymiopoulos,
Konstantinos Smpoukis,
Emmanouel Varvarigos
Abstract:
Recently there have been several historical changes in electricity networks that necessitate the development of Demand Side Management (DSM). The main objective of DSM is to achieve an aggregated consumption pattern that is efficient in terms of energy cost reduction, welfare maximization and satisfaction of network constraints. This is generally envisaged by encouraging electricity use at low-pea…
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Recently there have been several historical changes in electricity networks that necessitate the development of Demand Side Management (DSM). The main objective of DSM is to achieve an aggregated consumption pattern that is efficient in terms of energy cost reduction, welfare maximization and satisfaction of network constraints. This is generally envisaged by encouraging electricity use at low-peak times. In this paper, we consider a system with strategic, price anticipating consumers with private preferences that choose their electricity consumption patterns so as to maximize their own benefit. In this context, we take on the problem of coordinating the consumers' consumption behavior without sacrificing their welfare (Quality of Experience). In order to tackle this problem, we draw on concepts of indirect mechanism design and propose a DSM architecture that is able to fulfill specific system-wide constraints (e.g. energy cost reduction) and simultaneously achieve welfare that is very close to optimal. The proposed billing rule preserves both the budget-balance and the individual rationality properties. According to our evaluation, the proposed DSM architecture achieves a close to optimal allocation (1%-3% gap), compared to an "optimal" system that would use central optimization of user loads without user consensus or protection of their privacy
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Submitted 25 February, 2019;
originally announced February 2019.
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Incentive Compatibility, Scalability and Privacy in real time Demand Response
Authors:
Georgios Tsaousoglou,
Konstantinos Steriotis,
Nikolaos Efthymiopoulos,
Prodrommos Makris,
Emmanouel Varvarigos
Abstract:
The high penetration of Renewable Energy Sources in modern smart grids necessitated the development of Demand Response (DR) mechanisms as well as corresponding innovative services for the emerging flexibility markets. From a game theoretic perspective, the basic key performance indicators (KPIs) for such DR mechanisms are efficiency in terms of social welfare, practical applicability, and incentiv…
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The high penetration of Renewable Energy Sources in modern smart grids necessitated the development of Demand Response (DR) mechanisms as well as corresponding innovative services for the emerging flexibility markets. From a game theoretic perspective, the basic key performance indicators (KPIs) for such DR mechanisms are efficiency in terms of social welfare, practical applicability, and incentive guarantees, in the sense of making it a dominant strategy for each user to act truthfully according to his/her preferences, leaving no room for cheating. In this paper, we propose a DR architecture, including a mechanism based on Ausubel clinching auction and a communication protocol, that provably guarantee both efficiency and truthful user participation. Practicality/easiness of participation is enhanced via simple queries, while user privacy issues are addressed via a distributed implementation. Simulation results confirm the desired properties, while also showing that the truthfulness property becomes even more important in markets where participants are not particularly flexible
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Submitted 25 February, 2019;
originally announced February 2019.
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A stochastic approximation method for price-based assignment of autonomous EVs to Charging Stations
Authors:
Georgios Tsaousoglou,
Konstantinos Steriotis,
Emmanouel Varvarigos
Abstract:
This paper proposes a method for the stochastic estimation of Charging Stations prices based on dual decomposition. Prices are determined so as to minimize the social cost of the EVs while satisfying their constraints in expectation
This paper proposes a method for the stochastic estimation of Charging Stations prices based on dual decomposition. Prices are determined so as to minimize the social cost of the EVs while satisfying their constraints in expectation
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Submitted 25 February, 2019;
originally announced February 2019.