Inverter-embedded DFIG Rotor Winding Insulation Testing for Wind Energy Applications

• Published in: 2023 IEEE Energy Conversion Congress and Exposition (ECCE) pp. 273 - 279
• Main Authors: Park, Cheol-Hui, Bolanos, Adrian Jose Salcedo, Byun, Namhyuk, Lee, Sang Bin, Zapico, Marcos Orviz, Reigosa, David Diaz, Del Blanco, Fernando Briz, Osama, Mohamed
• Format: Conference Proceeding
• Language: English
• Published: IEEE 29.10.2023
• Subjects: Capacitance; Dissipation Factor; Doubly fed induction generators; Doubly-fed Induction Generator; Fault Diagnosis; Insulation; Insulation testing; Inverter; Maintenance engineering; Off-line Testing; Partial Discharge; Partial discharges; Rotor Insulation Testing; Rotors; Windings
• ISSN: 2329-3748
• DOI: 10.1109/ECCE53617.2023.10362478

Failure in the rotor winding insulation of doubly-fed induction generators (DFIG) used in wind turbines is common due to the harsh environment and operating stresses. However, rotor insulation testing is difficult and costly due to limited accessibility of wind generators installed inside the nacelle at remote locations. Therefore, remote and automated insulation testing can help reduce the maintenance cost and improve the reliability of DFIGs. In this paper, a new approach for testing the condition of rotor winding insulation for DFIGs is proposed. The main idea is to use the rotor-side inverter to perform off-line insulation testing whenever the wind generator is stopped. New test methods for partial discharge (PD), capacitance (C), and dissipation factor (DF) testing based on impulse and common mode voltage injection are proposed. Testing on a 6.3 kW wound rotor induction machine under emulated insulation defects is performed to verify that the proposed method can provide automated inverter-embedded testing for assessing the integrity of the DFIG rotor insulation.