Analysis of Hydroturbine Synchronous Generator Saturation Characteristics Based on Steady-State Measurements

Abstract

The paper describes the procedure for modeling the saturation of the main magnetic circuit of a synchronous hydrogenerator, which is based on measuring synchronous reactances at a series of stationary operating points. For this purpose, measurements were carried out on a 34 MVA generator in the Peruca HPP, on the basis of which the values ​​of the synchronous reactances in the d- and q-axes were determined. Using these results, a saturation model of the generator’s main magnetic circuit was defined as the dependence of the synchronous reactances on the magnetomotive force in the d- and q-axes. The developed model uniquely defines the generator’s saturation characteristics in the stationary state, and the saturation surface obtained in this way very well approximates the actual saturation of the machine’s magnetic circuit. The developed saturation model was used, among other things, to analyze the effect of transverse magnetization. In addition, an algorithm was defined by which, using an iterative procedure, the simulation of the generator’s stationary characteristics is carried out, taking into account the influence of saturation. A comparison of simulated and measured quasi-stationary responses on the generator at HPP Peruca was conducted, and excellent agreement between simulation results and measurements was obtained, confirming the validity of the developed saturation model.

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.