Transient frequency control with regional cooperation for power networks

TL;DR

This paper introduces centralized and distributed control strategies to keep power network frequencies within safe limits during transients while ensuring overall stability, using convex optimization and regional information sharing.

Contribution

It presents a novel convexification approach for transient frequency control and extends it to a distributed scheme with local information access.

Findings

Effective transient frequency regulation demonstrated on IEEE-39 network.

Convexification technique simplifies non-convex optimization problems.

Distributed control achieves similar stability with regional information constraints.

Abstract

This paper proposes a centralized and a distributed sub-optimal control strategy to maintain in safe regions the real-time transient frequencies of a given collection of buses, and simultaneously preserve asymptotic stability of the entire network. In a receding horizon fashion, the centralized control input is obtained by iteratively solving an open-loop optimization aiming to minimize the aggregate control effort over controllers regulated on individual buses with transient frequency and stability constraints. Due to the non-convexity of the optimization, we propose a convexification technique by identifying a reference control input trajectory. We then extend the centralized control to a distributed scheme, where each subcontroller can only access the state information within a local region. Simulations on a IEEE-39 network illustrate our results.