Wang, LixinNiu, TianhongSun, ZhenglongGao, HanJiang, ShouqiCai, GuoweiLie, Tek Tjing2026-06-112026-06-112026-06-08IEEE Transactions on Instrumentation and Measurement, ISSN: 0018-9456 (Print); 1557-9662 (Online), Institute of Electrical and Electronics Engineers (IEEE), 1-1. doi: 10.1109/tim.2026.36996310018-94561557-9662http://hdl.handle.net/10292/21367Synchrophasor-based sub-synchronous oscillations (SSOs) parameter identification is effective for monitoring SSOs, while its performance is significantly degraded by measurement noise, posing challenges to reliable parameter identification. This paper proposes a novel technique using multi-channel enhanced synchro-reassigning transform (MESRT) for robust and accurate SSO parameter identification. First, each measurement channel is transformed using the short-time Fourier transform (STFT) to construct a global multi-channel time-frequency (TF) representation. Then, an average modal energy-based strategy is developed to eliminate noise-induced spurious modes in the STFT spectrum. Subsequently, a three-step selection rule is applied to extract TF coefficients representing oscillation modes, from which the time-domain components are reconstructed. Finally, the Hilbert transform (HT) method is employed to identify the oscillation frequency and damping factor of each mode. The proposed MESRT method effectively improves the noise immunity and accuracy of conventional SRT by considering inter-channel correlations and leveraging modal energy to remove spurious modes. Case studies validate that the proposed method performs exceptionally well in terms of accuracy and noise robustness, demonstrating superior performance compared to existing methods.This article has been accepted for publication in IEEE Transactions on Instrumentation and Measurement. This is the author's version which has not been fully edited and content may change prior to final publication.0299 Other Physical Sciences0906 Electrical and Electronic EngineeringElectrical & Electronic Engineering4006 Communications engineering4008 Electrical engineering4009 Electronics, sensors and digital hardwareSub/super-synchronous oscillationsparameter identificationmulti-channel enhanced synchro-reassigning transform (MESRT)synchrophasornoiseJournal ArticleOpenAccess10.1109/tim.2026.3699631