FESTLIED: Fast Electrical system Simulation Through Linear Implicit Equilibrium Dynamics

• Applicants: Professor Dr.-Ing. Antonello Monti; Dr. Dirk Zimmer
• Subject Area: Electrical Energy Systems, Power Management, Power Electronics, Electrical Machines and Drives
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 571199796

Power systems are going through a fundamental transformation both on the generation and load side. The common denominator of this process is a significant growth in the presence of interfaces based on power electronics converter. As result, the whole infrastructure is progressively becoming a programmable electronic system while before used to be an electromechanical system. This process of transformation means that we are converging towards a more complex system in which modeling and simulation will play an even more relevant role both for planning and operation. Many (hundreds of) thousands of scenarios need to be computed, i.e simulated, upfront to find an optimal solution and ensure a safe operation even under critical conditions. Unfortunately, these simulation tasks still pose major challenges. Despite having many mature simulation tools available, there remain three major hurdles that make the fast simulation of large power grids still difficult even today: 1) The algebraic formulation for the energy distribution across many components leads to large non-linear equation systems whose solution is either difficult to determine or even ambiguous. 2) The direct formulation of dynamics (often in order to break up these large algebraic system) introduces fast dynamics (high frequencies) and drastically impairs the performance of classical Ordinary Differential Equations (ODE) solvers. 3) Whereas large non-linear systems already pose major problems during simulation, the often pose an even greater problem at initialization where no prior state value is available. It is the aim of this research project to remove these blocking hurdles by a fundamentally revised modeling approach. The result will be achieved by migrating in power system an innovative modeling approach that has proven successful in solving similar issues in Thermofluid dynamic and multi-body mechanics simulation. This modeling approach is called Linear Implicit Equilibrium Dynamics (LIED) and uses a split interface within its components (or sub-systems) that enables a separation from an explicit non-linear part from an implicit linear part. This combines the best of both: the linear equation system guarantees a robust solution under all conditions but is yet powerful enough to suppress unwanted high-frequency behavior. On the other hand, the non-linear part can still be expressed but is guaranteed to be available in explicit form. FESTLIED will develop the fundamental theory that will make the use of the LIED approach possible in the electrical energy sector while developing prototypical libraries to be used as test and verification of the new approach. A set of realistic scenarios will be used to fully prove the value of the new approach opening completely new scenarios in terms of computability in the field of energy networks.

• DFG Programme: Research Grants