Electromagnetic Transient Modeling of Converter Interactions in Northern Germany
This project focuses on the electromagnetic transient (EMT) modeling and analysis of complex interactions between power-electronic converter stations in northern Germany. The study addresses the close coupling between HVDC links, large-scale electrolyzers, and wind farm converters, which operate within low-impedance networks and are increasingly concentrated in the same geographical area.
A comprehensive EMT modeling framework is developed in PSCAD to represent converter-based systems and their mutual interactions under disturbed grid conditions. The study extends beyond individual installations to a wide-area EMT domain, enabling the investigation of voltage control conflicts, harmonic interactions, commutation failures, and fault recovery phenomena across multiple converter stations.
The project aims to support early detection of converter interaction risks and provide insights for system design, planning, and operation.
Contact Person: Eraldo Nika
Bridging Energy System Planning and Dynamic Power System Analysis
This project develops a framework that connects techno-economic energy system models with dynamic power system simulations to improve operational planning and stability assessment in future transmission networks. It enables a seamless transition from optimized expansion scenarios to dynamic feasibility studies, ensuring that long-term energy plans remain operationally secure under realistic grid conditions.
The framework automates the conversion of PyPSA-Eur outputs into DIgSILENT PowerFactory dynamic models, allowing the simulation of thousands of operating conditions and fault scenarios. This integration supports the screening of dynamic security risks across a wide range of system operating conditions.
In addition, the tool can be used for the analysis of large-scale grid disturbances and for root-cause identification following system events.
Designed for scalability, the approach can be applied to national and continental-scale power systems, at both the transmission and distribution levels, supporting decision-making in network expansion, system reliability, and the integration of emerging technologies.
Contact Person: Eraldo Nika
Screening Framework for Dynamic Security Assessment
This project develops a toolbox for screening dynamic stability risks in power systems using system estimates obtained immediately after contingencies. The method is based on the current-impacts formulation, which describes how active and reactive current imbalances are distributed among synchronous machines right after a fault or outage.
The approach estimates the initial accelerations of generators directly from network and machine data, without requiring full dynamic simulations. These early accelerations are then used to identify critical operating conditions and faults.
The ongoing work focuses on defining screening metrics that can indicate high-risk conditions for transient instability, supporting large-scale dynamic security assessment in future systems.
Contact Person: Eraldo Nika
Impact of Large-Scale Thyristor-Controlled Electrolyzers on Post-Fault Voltage Recovery
This project investigates the impact of large-scale electrolyzer plants supplied by six-pulse thyristor rectifiers on post-fault voltage recovery in transmission systems. A validated root-mean-square (RMS) dynamic model of the electrolyzer is scaled up and integrated into a detailed model of the German transmission grid. Scenarios with high grid utilization, strong power transfer, and low inertia are analyzed.
During nearby three-phase short circuits, electrolyzers with fault-ride-through (FRT) capability remain connected and rapidly ramp up their active power demand after fault clearance, increasing the inductive reactive power demand of the rectifier.
The project evaluates technical requirements for reactive power compensation during FRT events that support stable voltage recovery and secure integration of hydrogen production facilities into the transmission system.
Contact Person: Eraldo Nika