Torque preservation in DFIG systems during voltage dips with modulated stator-connected dynamic braking resistor

This article proposes a novel approach to enhancing the low-voltage ride-through capability of doubly-fed induction generator wind turbines using a dynamically modulated braking resistor (DBR) connected in series with the stator windings. Unlike conventional DBR-based methods that focus primarily on...

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Bibliographic Details
Authors: Baum, Filip, López Taberna, Jesús, Samanes Pascual, Javier, Bauer, Jan
Format: article
Status:Versión aceptada para publicación
Publication Date:2025
Country:España
Institution:Universidad Pública de Navarra
Repository:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/55761
Online Access:https://hdl.handle.net/2454/55761
Access Level:Open access
Keyword:Doubly-fed induction generator (DFIG)
Low-voltage ride-through (LVRT)
Voltage dip
Field-oriented control (FOC
Description
Summary:This article proposes a novel approach to enhancing the low-voltage ride-through capability of doubly-fed induction generator wind turbines using a dynamically modulated braking resistor (DBR) connected in series with the stator windings. Unlike conventional DBR-based methods that focus primarily on mitigating electrical transients, the proposed approach emphasizes maintaining the generator’s electromagnetic torque at its prefault level during grid voltage dips. The DBR resistance is calculated in real time based on analytical expressions derived from the system’s model. By properly selecting the DBR resistance during the fault, the excess mechanical power that cannot be transferred to the grid is dissipated within the resistor, allowing the generator torque to remain constant during the fault, which helps maintain rotor speed and mitigate electrical transients. The proposed strategy is validated through both simulation and experimental results under symmetrical fault conditions, demonstrating superior torque stability, reduced current transients, and improved postfault recovery compared to fixed-resistance DBR schemes.