Open Access

ARTICLE

A Time-Varying Subsynchronous Oscillation Suppression Strategy for DFIG-Based Wind Farms Using a Dual-Layer Adaptive Bandpass Filter

Dexin Li^1,2, Song Gao², Rui Xu¹, Cong Sun^1,*, Heling Yang¹
1 Department of Electric Engineering, Northeast Electric Power University, Jilin, China
2 State Grid JiLin Electric Power Research Institute, Changchun, China
* Corresponding Author: Cong Sun. Email:
(This article belongs to the Special Issue: Advances in Grid Integration and Electrical Engineering of Wind Energy Systems: Innovations, Challenges, and Applications)

Energy Engineering https://doi.org/10.32604/ee.2026.076664

Received 24 November 2025; Accepted 02 April 2026; Published online 29 June 2026

Abstract

Sub-synchronous oscillations (SSOs) have become a growing concern in DFIG (Doubly fed Induction Generator)-based wind farms due to complex interactions between converter control and grid dynamics. This paper proposes a time-varying oscillation suppression strategy based on a Dual-Layer Adaptive Band-Pass filter (DL-ABPF). The outer-layer filter separates and tracks the target oscillation mode, while the inner-layer filter is activated under dual discriminant criteria to achieve real-time directional damping. Within a wide-area monitoring framework, the strategy employs secondary dynamic data storage and the ESPRIT algorithm for online identification of modal frequency and damping factor. Once activated, the inner filter updates its central frequency adaptively, and the filtered signal is injected into the converter controller through a damping feedback channel, forming a closed-loop structure of “monitoring–discrimination–suppression”. Simulation studies under sub-synchronous control interaction (SSCI) and sub-synchronous resonance (SSR) conditions verify that the proposed method can continuously track and suppress oscillations under frequency drift and parameter variations. Unlike conventional single-layer filtering schemes that primarily perform monitoring, the DL-ABPF integrates monitoring and suppression within a unified framework, and its effectiveness under frequency drift and operating-condition variations is illustrated in the presented case studies.

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Keywords

Adaptive oscillation suppression; DFIG-based wind farm; dual-layer adaptive band-pass filter; ESPRIT; sub-synchronous oscillation

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