Engineering, Energy, Transport AIC

Valerii HRANIAK – Candidate of Technical Sciences, Associate Professor, Associate Professor of the Department of Mathematics and Informatics, Mykhailo Kotsiubynskyi Vinnytsia State Pedagogical University (32, Ostrozkogo St., Vinnytsia, 21008, Ukraine, e-mail: titanxp2000@ukr.net, https://orcid.org/0000-0001-6604-6157).
Oleh HAYDAMAK – Candidate of Technical Sciences, Associate Professor, Associate Professor of the Department of Power engineering, electrical engineering and electromechanics of Vinnitsa National Agrarian University (3 Soniachna St., Vinnitsa, Ukraine, 21008, e-mail: haidamak@vsau.vin.ua, https://orcid.org/0000-0001-5116-6017).

The article addresses the issue of detecting inter-turn insulation defects in the field windings of a power generator rotor at early stages of their development, which is critically important for ensuring the reliable and safe operation of power equipment. A new thermal diagnostic method is proposed, based on measuring the coolant temperature in the end region of the rotor's cooling system. When combined with correction coefficients for temperature rise in individual excitation windings, this approach enables highly accurate identification of local overheating zones. This, in turn, serves as an indicator of the presence of inter-turn insulation defects, regardless of their formation mechanism—whether due to partial discharges, mechanical damage, or thermal aging. A key advantage of the method lies in its capability to diagnose insulation defects early, before they reach a critical stage, allowing maintenance to be carried out before significant deterioration in operational characteristics occurs.
In addition, a structural diagram of a new control device has been developed to implement the proposed method. A major feature of this design is the non-contact nature of temperature measurement of the field windings, which eliminates the influence of additional components on rotor balancing and avoids introducing asymmetry into its mechanical structure. The use of a synchronization system ensures high precision in spatial positioning and selective temperature measurement at specific monitored points, providing maximum in formativeness and diagnostic value of the obtained data. The proposed approach can be effectively integrated into modern condition monitoring systems for power units, thereby enhancing the overall safety and reliability of the equipment. The research results open new prospects for further development of thermal diagnostic methods in the field of power engineering, particularly for complex objects with limited access to structural elements during operation.

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