On-Line Determination of Hydrogenerator Synchronous Reactances

Abstract

The paper presents the procedure for identifying the synchronous reactance in the longitudinal and transverse axis of the hydrogenerator during operation (on-line), which is based on the measurements that are available within the diagnostic monitoring system of the hydrogenerator. Two identification procedures were considered. The first is based on measurements in a stationary operating point and knowledge of the excitation current reduction factor, and the second is based on the recording of quasi-stationary responses in the environment of the operating point and the application of the appropriate estimation algorithm. It is shown that the second procedure, which is theoretically correct, cannot be applied in real operating conditions. In the first procedure, the excitation current reduction factor is determined based on the generator’s idle and short-circuit characteristics. The measurements were performed on the generator at HE Peruca (26 MVA), and the results of the synchronous reactance measurements in the longitudinal and transverse axes obtained for different operating points of the generator are presented. Also shown are the results of measuring the stray reactance of the armature winding of the same generator.

Marin Despalatović

Full Professor | Department of Electrical Drives and Industrial Control

Full professor at the Faculty of Electrical Engineering, Mechanical Engineering, and Naval Architecture in Split, where he teaches courses Electric Machines, Electric Drive Systems, and Electromechanical System Modeling. His research focuses on power systems, energy storage, and smart grid technologies, with active participation in multiple national and international projects aimed at advancing energy infrastructure and improving system stability.

Božo Terzić

Full Professor | Department of Electrical Drives and Industrial Control

Full professor at the Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture in Split, with significant contributions in the field of industrial development projects including the design of prototypes of electronic converters used in industrial plants around the world. His research interests are focused on the application of electronic converters in electric drives and renewable energy sources.