Small-Signal Stability Oriented Real-Time Operation of Power Systems with a High Penetration of Inverter-Based Resources

TL;DR

This paper introduces a real-time control strategy for power systems with high inverter-based resources, ensuring optimal operation while maintaining small-signal stability through offline analysis and online feedback optimization.

Contribution

It presents a novel two-stage approach combining data-driven stability analysis with real-time feedback control for stable inverter-based power system operation.

Findings

Effective stability preservation demonstrated on IEEE 9-bus test case

Data-driven stability index accurately predicts stability margins

Online optimization maintains optimal and secure operating points

Abstract

This study proposes a control strategy to ensure the safe operation of modern power systems with high penetration of inverter-based resources (IBRs) within an optimal operation framework. The objective is to obtain operating points that satisfy the optimality conditions of a predefined problem while guaranteeing small-signal stability. The methodology consists of two stages. First, an offline analysis of a set of operating points is performed to derive a data-driven regression-based expression that captures a damping-based stability index as a function of the operating conditions. Second, an Online Feedback Optimization (OFO) controller is employed to drive the system toward an optimal operating point while maintaining a secure distance from the instability region. The proposed strategy is evaluated on an academic test case based on a modified version of the IEEE 9-bus system, in which synchronous generators are replaced by IBRs operating under both grid-following and grid-forming control modes. The results demonstrate the effectiveness of the method and are discussed in detail.