Estimation of Participation Factors for Power System Oscillation from Measurements

TL;DR

This paper introduces a measurement-based method to estimate participation factors in power system oscillations, improving accuracy by transforming measurement space and applicable to large systems with inverter-based resources.

Contribution

It presents a novel approach to estimate participation factors directly from measurements, relaxing symmetry assumptions and enhancing accuracy over traditional model-based methods.

Findings

Method accurately estimates participation factors from measurements.

Approach works on large systems including 48-machine NPCC system.

Effective even with inverter-based resource penetration.

Abstract

In a power system, when the participation factors of generators are computed to rank their participations into an oscillatory mode, a model-based approach is conventionally used on the linearized system model by means of the corresponding right and left eigenvectors. This paper proposes a new approach for estimating participation factors directly from measurement data on generator responses under selected disturbances. The approach computes extended participation factors that coincide with accurate model-based participation factors when the measured responses satisfy an ideally symmetric condition. This paper relaxes this symmetric condition with the original measurement space by identifying and utilizing a coordinate transformation to a new space optimally recovering the symmetry. Thus, the optimal estimates of participation factors solely from measurements are achieved, and the accuracy and influencing factors are discussed. The proposed approach is first demonstrated in detail on a two-area system and then tested on an NPCC 48-machine power system. The penetration of inverter-based resources is also considered.