Detection, Discrimination, and Localization of Rotor Winding Faults in Doubly Fed Induction Generators Using a...

Area of Science:

• Electrical Engineering
• Power Systems
• Machine Diagnostics

Background:

• Doubly fed induction generators (DFIGs) are vital for variable speed energy systems.
• Rotor winding faults, like high-resistance connections (HRC) and inter-turn short circuits (ITSC), pose significant challenges due to similar current distortions and DFIG operational dynamics.
• Reliable fault detection is essential for system resilience.

Purpose of the Study:

• To propose a novel, three-layer diagnostic framework (ZSC-CASI-CADI) for comprehensive rotor winding fault diagnosis in DFIGs.
• To enable accurate detection, discrimination between fault types, and localization of faulty phases.

Main Methods:

• The ZSC-CASI-CADI framework utilizes three-phase rotor currents and rotor zero-sequence current (ZSC).
• Fault detection is performed using ZSC magnitude.
• The Cosine Angle Spread Indicator (CASI) differentiates HRC from ITSC faults by analyzing rotor current phasor dispersion.
• The Current Angle Difference Indicator (CADI) identifies the specific faulty phase based on angular deviations.

Main Results:

• Extensive simulations validate the framework's accuracy and real-time capabilities.
• The method successfully detects, discriminates, and localizes DFIG rotor winding faults under various operating conditions (sub-synchronous and super-synchronous modes).
• The framework demonstrates effectiveness across different load and rotor speed scenarios.

Conclusions:

• The proposed ZSC-CASI-CADI framework offers a light and effective solution for DFIG rotor winding fault monitoring.
• This approach enhances the reliability and resilience of variable speed energy systems by enabling prompt and precise fault management.