Tuning a Cascaded Online Feedback Optimization Controller for Provision of Distributed Flexibility

TL;DR

This paper investigates how tuning parameters in a cascaded online feedback optimization control system affects the efficiency and accuracy of distributed flexibility provision in power grids, demonstrating the importance of careful parameter selection.

Contribution

It provides an analysis of parameter influence in a hierarchical control structure for distributed flexibility, highlighting interdependencies and tuning strategies for improved performance.

Findings

Parameter tuning significantly impacts control accuracy and speed.

Interdependencies exist between controllers affecting overall system behavior.

Proper tuning enables efficient hierarchical coordination of flexibility units.

Abstract

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 flexibility request at a point of common coupling can be met by utilizing a cascaded control structure based on online feedback optimization. In this paper the influence of the parameterization of the individual controllers on the performance of the hierarchical flexibility provision is studied on a three-level test system. The results show a high interdependency between the choice of control parameters of one controller and the behavior of other controllers as well as a significant impact on the accuracy and speed of flexibility provision. With a careful tuning, a cascaded structure based on online feedback optimization can achieve efficient vertical coordination of flexibility providing units.