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This paper assesses the impact of electric vehicles (EVs) providing primary frequency regulation via vehicle-to-grid (V2G) technology. The aim of the work is to define a set of recommendations in order to guarantee a stable large-scale deployment of EV fleets as primary reserve providers. A realistic fleet model is proposed, which emulates the aggregated response of a number of EVs characterized by V2G hardware response times derived in laboratory tests. The effects of primary frequency control via EV fleets replacing conventional generating units are assessed with a sensitivity study in a single-bus power system with growing fleet sizes and response times. Two recommendations are derived to guarantee safe and stable operation: Recommendation 1 requires the share of EVs providing primary reserve to be smaller than the reserve from conventional units; Recommendation 2 requires response times below a given limit value, calculated as a function of the following power system parameters: the system inertia, the total primary reserve over the rotating generation capacity, and the employed droop gain. The full 60 kV power system of the Danish island of Bornholm is then employed to evaluate the validity of the proposed requirements on a real system with complex dynamics, non-linearities and voltage dependencies.

In the wake of the widespread deployment of Renewable Energy Sources (RESs) and the introduction of other distributed energy technologies, the grid exhibits faster and more intricate dynamics. A lot of attention is therefore being put on automated grid management systems, which entail a shift in the role and tasks of human operators in the Control Rooms (CRs). Given the rapid pace of development, the question ultimately arises if human guidance is necessary at all to safely operate the grid. This work investigates the prospective role of the human operators in CRs under consideration of cognitive challenges in highly automated power systems, aiming to maintain safe and efficient grid operation. A review on relevant literature casts light on the scope of influence of automated grid management systems, the operational states of power system that will still require human assistance, as well as activities and interactions. Finally, recommendations on the design of Decision Support Systems (DSS) supporting humans in their future role are provided.

The provision of ancillary services is an additional revenue stream for the owners of inverter-equipped storagesystems, such as batteries and electric vehicles. As real demonstrations have shown, primary frequency control(PFC) is a suitable and economically viable service for small-scale energy storage (ES) systems. This paperproposes a decentralized stochastic control policy, which significantly reduces ES units’ losses when providingPFC. The proposed controller can be tuned to obtain the desired service reserve provision errors, while achievinga balance between tracking accuracy and efficiency. An extension of the algorithm significantly reduces theswitching rate of the devices by up to 95%. Analytical expressions for the reserve errors and the switching rates,dependent on the aggregation size and the controllers’ settings, are derived and verified by simulations.Simulation results show that the proposed controller can significantly reduce ES units’ losses when they areproviding PFC by 8–15.5%, while achieving the expected tracking pe

This paper applies a robust optimization technique for coordinating reserve allocations in multiple-cell based power systems. The linear decision rules (LDR)-based policies were implemented to achieve the reserve robustness, and consist of a nominal power schedule with a series of linear modifications. The LDR method can effectively adapt the participation factors of reserve providers to respond to system imbalance signals. The policies considered the covariance of historic system imbalance signals to reduce the overall reserve cost. When applying this method to the cell-based power system for a certain horizon, the influence of different time resolutions on policy-making is also investigated, which presents guidance for its practical application. The main results illustrate that: (a) the LDR-based method shows better performance, by producing smaller reserve costs compared to the costs given by a reference method; and (b) the cost index decreases with increased time intervals, however, longer intervals might result in insufficient reserves, due to low time resolution. On the other hand, shorter time intervals require heavy computational time. Thus, it is important to choose a proper time interval in real time operation to make a trade off.

This report summarizes the evaluation and validation of the ELECTRA Web-of-Cells concept which has been implemented for the proof of concept in selected validation environments provided by the project partners. The performed experiments have been realized in simulations and in laboratory environments and showed the feasibility of the Web-of-Cells concept and integrated functions for balancing and voltage control. Future work is necessary to further refine the concept and functions and to focus the controller implementations on higher technology readiness levels.

Here, the authors analyse the operator point of view of the Web-of-Cells concept defined in the EU project ELECTRA, by identifying operator tasks into the supervision of a highly automated power system, and the information requirements to facilitate appropriate operator situation awareness. The study outlines the methodology adopted, which is based on the cognitive work analysis framework, to provide an overview of the most interesting scenarios and to summarise the requirements analysis results. In order to derive required control room functionality, a set of relevant control room scenarios have been identified based on the Web-of-Cells control concept. The authors considered scenarios that challenge traditional control schemes, scenarios that caused major failures (i.e. blackouts), and scenarios that can be expected to appear in the future. For each scenario, information concerning network layout, triggering events, physical constraints, manually/automatic operations, operators' tasks, and relevant analytics have been analysed.

This paper presents initial laboratory experiments designed to test belief-desire-intention agent reasoning in a webof-cell context. The work introduces the application of the bridge between JASON and the Common Artifact Infrastructure for Agents Open Environments to agent and environment modeling, respectively. Belief-desire-intention reasoning is achieved through JASON’s engine while artifacts monitor and control grid devices using dedicated JAVA objects. Experiments have been conducted in SYSLAB, a testbed for distributed power system control and distributed solutions, located at the Risø campus of the Technical University of Denmark. Experimental results show the feasibility of applying belief-desire-intention reasoning to WoC control using a test case where tie-line power flow setpoints must be followed