In this paper we propose an approach based on Online Feedback Optimization (OFO) controller with grid input–output sensitivity estimation for real-time operation, e.g., at subsecond time scales. The OFO uses measurements as feedback to update the value of controllable elements in grid, and track solution a time-varying AC Optimal Power Flow (AC-OPF). Instead relying full model, admittance matrix, only requires steady-state relating change inputs, power injections set-points, measured...

In this letter, we present a novel control scheme for feedback optimization. That is, propose discrete-time controller that can steer physical plant to the solution of constrained optimization problem without numerically solving problem. Our be interpreted as discretization continuous-time projected gradient flow. Compared other schemes used optimization, such saddle-point or inexact penalty methods, our approach combines several desirable properties: it asymptotically enforces constraints...

Optimization is an essential part of power grid operation and lately, Online methods have gained traction. One such method Feedback (OFO) which uses measurements from the as feedback to iteratively change control inputs until they converge solution optimization problem. Such algorithms been applied many system problems experimentally validated in lab setups. This paper implements OFO controller a real distribution for 24/7 using off-the-shelf hardware software. The proposed strategy...

Due to more volatile generation, flexibility will become important in transmission grids. One potential source of this can be distribution A request from the grid a then needs split up onto different Flexibility Providing Units (FPU)s grid. way do is Online Feedback Optimization (OFO). OFO new control method that steers power systems optimal solution an optimization problem using minimal model information and computation power. This paper show how choose tune controller. Afterward, we test...

The insulin sensitivity (IS) of the human body changes with a circadian rhythm. This adds to time-varying feature glucose metabolism process and places challenges on blood (BG) control patients Type 1 Diabetes Mellitus. paper presents Model Predictive Controller that takes periodic IS into account, in order enhance BG control. future effect is predicted using machine learning technique, namely, customized Gaussian Process (GP), based historical training data. data for GP continuously updated...

Online Feedback Optimization is a method used to steer the operation of process plant its optimal operating point without explicitly solving nonlinear constrained optimization problem. This achieved by leveraging linear model and feedback from measurements. However presence plant-model mismatch leads suboptimal results when using this approach. Learning enables overcome shortcoming. In work we present novel application with online adaptation Gaussian regression. We demonstrate our approach...

The human insulin-glucose metabolism is a time-varying process, which partly caused by the changing insulin sensitivity of body. This follows circadian rhythm and its effects should be anticipated any automated delivery system. paper presents an extension our previous work on developing controller suitable for humans with Type 1 Diabetes Mellitus. Furthermore, we enhance new kernel function Gaussian Process deal noisy measurements, as well as, training data Process, arising therefrom....

Distribution grid flexibility is regarded as a possible measure in curative system operation, yielding need for an efficient and robust coordination mechanism the joint provision by individual units to transmission grid. This paper introduces method coordinate distribution level fast-responding based on Online Feedback optimization. We utilize optimization algorithm closed loop with dispatch set points active reactive power providing units. The approach evaluated experimental setup,...

This paper provides insight into the position control of an electric power steering system to meet challenges autonomous driving. It builds on previous works in this field present advancement terms tracking performance and robustness. Furthermore approach presented here, including controller synthesis, has been validated a test vehicle under representative conditions.

Due to more volatile generation, flexibility will become important in transmission grids. One potential source of this can be distribution A request from the grid a then needs split up onto different providing units (FPU) grid. way do is Online Feedback Optimization (OFO). OFO new control method that steers power systems optimal solution an optimization problem using minimal model information and computation power. This paper show how choose tune controller. Afterward, we test resulting...

Utilizing distribution grid flexibility for ancillary services requires the coordination and dispatch of requested active reactive power to a large number distributed energy resources in underlying layers. This paper presents an approach hierarchically requests based on Online Feedback Optimization (OFO). We implement framework individual controllers coordinating actors, contributing provision, track operating point at interface between The is evaluated terms performance during possible...

Coordinating a high number of flexibility providing units (e.g. to provide ancillary services for the transmission system) across various grid layers requires new control concepts. A request at point common coupling can be met by utilizing cascaded structure based on online feedback optimization. In this paper influence parameterization individual controllers performance hierarchical provision is studied three-level test system. The results show interdependency between choice parameters one...

Utilizing distribution grid flexibility for ancillary services requires the coordination and dispatch of requested active reactive power to a large number distributed energy resources in underlying layers. This paper presents an approach hierarchically requests based on Online Feedback Optimization (OFO). We implement framework individual controllers coordinating actors, contributing provision, track operating point at interface between The is evaluated terms performance during possible...

The rise in residential photovoltaics (PV) as well other distributed energy sources poses unprecedented challenges for the operation of distribution grids. high active power infeed such during times peak production is a stress test which grids have usually not been exposed to past. When amounts are injected into grid, overall flow often limited because voltages reaching their upper acceptable limits. Volt/VAr methods aim raise this limit by controlling voltage using reactive power. This way,...

Curative or remedial actions are the set of immediate intended to bring power grid a safe operating point after contingency. The effectiveness these is essential guarantee curative <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$N$</tex> -1 security. Nowadays, derived ahead time, based on anticipated future state. Due shift from steady volatile energy resources, state will frequently change and would need be pre-planned increasingly often....

The increasing electric power consumption and the shift towards renewable energy resources demand for new ways to operate transmission subtransmission grids. Online Feedback Optimization (OFO) is a feedback control method that enables real-time, constrained, optimal of these Such controllers can minimize, e.g., curtailment losses while satisfying grid constraints like voltage current limits. We tailor extend OFO handle discrete inputs explain how design an controller grid. present novel...

In this paper, we study the stability and convergence of continuous-time Lagrangian saddle flows to solutions a convex constrained optimization problem. Convergence these is well-known when underlying function either strictly in primal or concave dual variables. show under non-strict convexity simple, unilateral augmentation term added. For purpose, establish novel, non-trivial characterization limit set saddle-flow trajectories that allows us preclude cycles. With our presentation try unify...

Optimization is an essential part of power grid operation and lately, Online methods have gained traction. One such method Feedback (OFO) which uses measurements from the as feedback to iteratively change control inputs until they converge solution optimization problem. Such algorithms been applied many system problems experimentally validated in lab setups. This paper implements OFO controller a real distribution for 24/7 using off-the-shelf hardware software. The proposed strategy...

Distribution grid flexibility is discussed as a possible measure in curative system operation, yielding need for an efficient and robust coordination mechanism the joint provision by individual units to transmission grid. This paper introduces method coordinate distribution level fast-responding based on Online Feedback Optimization. We utilize optimization algorithm closed loop with dispatch set points active reactive power providing units. The approach evaluated experimental setup,...

Online Feedback Optimization (OFO) controllers steer a system to its optimal operating point by treating optimization algorithms as auxiliary dynamic systems. Implementation of OFO requires setting the parameters algorithm that allows reaching convergence, posing challenge because convergence is often decoupled from performance controlled system. are also typically designed ensure steady-state tracking fixing sampling time be longer than constants In this paper, we first quantify impact and...