Abstract
The rapid expansion of offshore wind farms and the development of energy islands for green hydrogen production have introduced futuristic off-grid systems. These systems can experience total shutdowns, necessitating black start solutions to ensure reliable restoration capabilities for isolated offshore wind farms. This paper investigates a grid-forming converter sizing strategy to enable black start capabilities in off-grid offshore wind farms. The study evaluates the impact of different energization strategies on battery energy storage system (BESS) sizing, focusing on soft energization with droop control in wind turbines and electrolyzers, the effects of wind turbine ramp rates on BESS requirements, and the role of switchable shunt reactors at the offshore substation for reactive power management. A comparative analysis is conducted between soft + hard and pure soft energization sequences to assess their impact on BESS converter sizing. Results demonstrate that the combined soft + hard energization strategy significantly reduces BESS converter size, offering a more cost-effective black start solution compared to pure soft energization.

Abstract
Maintaining frequency stability is one of the biggest challenges facing future power systems, due to the increasing penetration levels of inverter-based renewable resources. This investigation experimentally validates the frequency provision capabilities of a real Polymer Electrolyte Membrane (PEM) hydrogen electrolyser (HE) using a power hardware-in-the-loop (PHIL) setup. The PHIL consists of a custom 3-level interleaved buck converter and a hardware platform for real-time control of the converter and conducting grid simulation, associated with the modelling of the future Iberian Peninsula (IP) and Continental Europe (CE) systems. The investigation had the aim of validating earlier simulation work and testing new responses from the electrolyser when providing different frequency services at different provision volumes. The experimental results corroborate earlier simulation results and capture extra electrolyser dynamics as the double-layer capacitance effect, which was absent in the simulations. Frequency Containment Reserve (FCR) and Fast Frequency Response (FFR) were provided successfully from the HE at different provision percentages, enhancing the nadir and the rate of change of frequency (RoCoF) in the power system when facing a large disturbance compared to conventional support only. The results verify that HE can surely contribute to frequency services, paving the way for future grid support studies beyond simulations.

Abstract
In a high-risk sector, such as power system, transparency and interpretability are key principles for effectively deploying artificial intelligence (AI) in control rooms. Therefore, this paper proposes a novel methodology, the evolving symbolic model (ESM), which is dedicated to generating highly interpretable data-driven models for dynamic security assessment (DSA), namely in system security classification (SC) and the definition of preventive control actions. The ESM uses simulated annealing for a data-driven evolution of a symbolic model template, enabling different cooperative learning schemes between humans and AI. The Madeira Island power system is used to validate the application of the ESM for DSA. The results show that the ESM has a classification accuracy comparable to pruned decision trees (DTs) while boasting higher global inter-pretability. Moreover, the ESM outperforms an operator-defined expert system and an artificial neural network in defining preventive control actions.

Abstract
This work proposes an innovative methodology for the optimal placement of grid-forming converters (GFM) in converter-dominated grids while accounting for multiple stability classes. A heuristic-based methodology is proposed to solve an optimisation problem whose objective function encompasses up to 4 stability indices obtained through the simulation of a shortlist of disturbances. The proposed methodology was employed in a modified version of the 39-bus test system, using DigSILENT Power Factory as the simulation engine. First, the GFM placement problem is solved individually for the different stability classes to highlight the underlying physical phenomena that explain the optimality of the solutions and evidence the need for a multi-class approach. Second, a multi-class approach that combines the different stability indices through linear scalarisation (weights), using the normalised distance of each index to its limit as a way to define its importance, is adopted. For all the proposed fitness function formulations, the method successfully converged to a balanced solution among the various stability classes, thereby enhancing overall system stability.

Abstract
The purpose of an Advanced Distribution Management System (ADMS) is to consolidate the key operational functions of a SCADA system, Outage management System (OMS) and Distribution Management System (DMS) into a unified platform. This includes several key functions: SCADA operation, incidents and outages management, teams and field works management including switching operations and advanced applications for network analysis and optimization. The new generation of ADMS also implements a predictive operation strategy to enhance real-time operator responsiveness. The innovative aspects related to the new generation of ADMS built on top of an open architecture will be presented in this paper. © The Institution of Engineering & Technology 2025.

Abstract
A Renewable Energy Management System (REMS) is designed to enhance the operation and efficiency of renewable energy assets, such as wind and solar power, by addressing their inherent variability. Through integration with Supervisory Control and Data Acquisition (SCADA) systems, REMS facilitates real-time adjustments and forecast-based decisions, enabling grid security, optimizing energy dispatch, and maximizing economic benefits. This paper introduces a versatile active power control methodology for renewable energy plants, capable of operating across various time scales to address technical and market-driven requirements. The proposed framework processes inputs from power system measurements to generate forecasts using two distinct approaches, optimizing setpoints for energy dispatch and control processes. Four optimization methods—merit order, weighted allocation, proportional allocation, and linear optimization—are employed to maximize power utilization while adhering to system constraints. The approach is validated for two control intervals: 4 seconds, representing rapid response for converter-based resources, and 15 minutes, simulating broader operational adjustments for reserve provision programs. This dynamic and scalable control framework demonstrates its potential to enhance the management, efficiency, and sustainability of renewable energy systems. © The Institution of Engineering & Technology 2025.