104 citations · 151 across the 23 of their papers we have counts for
26 papers
Flexibility aggregation via set projection for distribution grids with multiple interconnections
Maísa Beraldo Bandeira, Alexander Engelmann, Timm Faulwasser
With the increasing number of flexible energy devices in distribution grids, coordination between Transmission System Operators (TSOs) and Distribution System Operators (DSOs) beco…
Towards grid-aware multi-period flexibility aggregation - A constrained zonotope approach
Maurice Raetsch, Maísa Beraldo Bandeira, Christian Rehtanz +2
Aggregation schemes provide a means to reduce the computational complexity of power system operation by reducing the number of devices that are considered individually. This can be…
Complexity Reduction for TSO-DSO Coordination: Flexibility Aggregation vs. Distributed Optimization
Maísa Beraldo Bandeira, Alexander Engelmann, Timm Faulwasser
The increasing number of flexible devices and distributed energy resources in power grids renders the coordination of transmission and distribution systems increasingly complex. In…
Towards Data-Driven Multi-Stage OPF
Oleksii Molodchyk, Philipp Schmitz, Alexander Engelmann +2
The operation of large-scale power systems is usually scheduled ahead via numerical optimization. However, this requires models of grid topology, line parameters, and bus specifica…
Large problems are not necessarily hard: A case study on distributed NMPC paying off
Gösta Stomberg, Maurice Raetsch, Alexander Engelmann +1
A key motivation in the development of Distributed Model Predictive Control (DMPC) is to accelerate centralized Model Predictive Control (MPC) for large-scale systems. DMPC has the…
Decentralized Real-Time Iterations for Distributed NMPC
Gösta Stomberg, Alexander Engelmann, Moritz Diehl +1
This article presents a Real-Time Iteration (RTI) scheme for distributed Nonlinear Model Predictive Control (NMPC). The scheme transfers the well-known RTI approach, a key enabler…
Distributed Interior Point Methods for Optimization in Energy Networks
Alexander Engelmann, Michael Kaupmann, Timm Faulwasser
This note discusses an essentially decentralized interior point method, which is well suited for optimization problems arising in energy networks. Advantages of the proposed method…
Approximate Dynamic Programming with Feasibility Guarantees
Alexander Engelmann, Maisa B. Bandeira, Timm Faulwasser
Safe and economic operation of networked systems is often challenging. Optimization-based schemes are frequently considered, since they achieve near-optimality while ensuring safet…
Scalable Primal Decomposition Schemes for Large-Scale Infrastructure Networks
Alexander Engelmann, Sungho Shin, François Pacaud +1
The operation of large-scale infrastructure networks requires scalable optimization schemes. To guarantee safe system operation, a high degree of feasibility in a small number of i…
Decentralized non-convex optimization via bi-level SQP and ADMM
Gösta Stomberg, Alexander Engelmann, Timm Faulwasser
Decentralized non-convex optimization is important in many problems of practical relevance. Existing decentralized methods, however, typically either lack convergence guarantees fo…
Data-driven MPC of descriptor systems: A case study for power networks
Philipp Schmitz, Alexander Engelmann, Timm Faulwasser +1
Recently, data-driven predictive control of linear systems has received wide-spread research attention. It hinges on the fundamental lemma by Willems et al. In a previous paper, we…
Approximations for Optimal Experimental Design in Power System Parameter Estimation
Xu Du, Alexander Engelmann, Timm Faulwasser +1
This paper is about computationally tractable methods for power system parameter estimation and Optimal Experiment Design (OED). Here, the main motivation is that OED has the poten…
An essentially decentralized interior point method for control
Alexander Engelmann, Gösta Stomberg, Timm Faulwasser
Distributed and decentralized optimization are key for the control of networked systems. Application examples include distributed model predictive control and distributed sensing o…
A Distributed Active Set Method for Model Predictive Control
Gösta Stomberg, Alexander Engelmann, Timm Faulwasser
This paper presents a novel distributed active set method for model predictive control of linear systems. The method combines a primal active set strategy with a decentralized conj…
Essentially Decentralized Conjugate Gradients
Alexander Engelmann, Timm Faulwasser
Solving structured systems of linear equations in a non-centralized fashion is an important step in many distributed optimization and control algorithms. Fast convergence is requir…
Distributed Power Flow and Distributed Optimization -- Formulation, Solution, and Open Source Implementation
Tillmann Mühlpfordt, Xinliang Dai, Alexander Engelmann +1
Solving the power flow problem in a distributed fashion empowers different grid operators to compute the overall grid state without having to share grid models-this is a practical…
Online power system parameter estimation and optimal operation
Xu Du, Alexander Engelmann, Timm Faulwasser +1
The integration of renewables into electrical grids calls for optimization-based control schemes requiring reliable grid models. Classically, parameter estimation and optimization-…
Distributed Control of Charging for Electric Vehicle Fleets under Dynamic Transformer Ratings
Micah Botkin-Levy, Alexander Engelmann, Tillmann Mühlpfordt +2
Due to their large power draws and increasing adoption rates, electric vehicles (EVs) will become a significant challenge for electric distribution grids. However, with proper char…
ALADIN- -- An open-source MATLAB toolbox for distributed non-convex optimization
Alexander Engelmann, Yuning Jiang, Henrieke Benner +3
This paper introduces an open-source software for distributed and decentralized non-convex optimization named ALADIN-. ALADIN- is a MATLAB implementation of tailored variants…
Optimal Experiment Design for AC Power Systems Admittance Estimation
Xu Du, Alexander Engelmann, Yuning Jiang +2
The integration of renewables into electrical grids calls for the development of tailored control schemes which in turn require reliable grid models. In many cases, the grid topolo…
Feasibility vs. Optimality in Distributed AC OPF - A Case Study Considering ADMM and ALADIN
Alexander Engelmann, Timm Faulwasser
This paper investigates the role of feasible initial guesses and large consensus-violation penalization in distributed optimization for Optimal Power Flow (OPF) problems. Specifica…
Decomposition of non-convex optimization via bi-level distributed ALADIN
Alexander Engelmann, Yuning Jiang, Boris Houska +1
Decentralized optimization algorithms are important in different contexts, such as distributed optimal power flow or distributed model predictive control, as they avoid central coo…
Distributed State Estimation for AC Power Systems using Gauss-Newton ALADIN
Xu Du, Alexander Engelmann, Yuning Jiang +2
This paper proposes a structure exploiting algorithm for solving non-convex power system state estimation problems in distributed fashion. Because the power flow equations in large…
Towards economic NMPC for multi-stage AC optimal power flow
Timm Faulwasser, Alexander Engelmann
Recently there has been considerable progress on the analysis of stability and performance properties of so-called economic Nonlinear Model Predictive Control (NMPC) schemes; i.e.…