Hydrogenerator Monitoring
Abstract
The study can be divided into two characteristic parts: study and research. The study part, which includes chapters 2 and 3, first provides an overview of the state and development of hydropower unit monitoring, which is based on available literature and the experiences of international and domestic companies in this field. Furthermore, the monitoring of individual quantities that are included in standard diagnostic monitoring, such as vibrations, partial outages, air gap and magnetic induction in the air gap, is described in detail. The research part of the study includes chapters 4 and 5. Chapter 4 describes a system called monitoring of electrical quantities of hydrogenerators. This system was installed on generator 1 in HPP Peruca, for experimental purposes, and was defined in such a way that it includes quantities that are relevant for the behavior of the generator in stationary and dynamic states. These are armature voltages and currents, excitation voltage and current, rotor position and field in the air gap. The system was built in cooperation between HEP, FESB Split and VESKI Zagreb, and represents a logical extension of the transient monitoring system previously developed by the aforementioned company. One feature of the system is the measurement of instantaneous voltage and current values, as opposed to the usual monitoring of effective values when currents and voltages are introduced into the monitoring system as process variables. Another feature is the introduction of the rotor rotation angle into the monitoring of hydropower units, which was done to determine the generator load angle. In this way, the conditions for the application of a mathematical model of the generator for the analysis and diagnostics of operating events would be met. The application of mathematical models for the purpose of diagnostic analyses is also a modern trend in the monitoring of industrial plants. For example, in electric motor drives with asynchronous motors, where voltages, currents and rotation speed are recorded for this purpose. The experimental system for monitoring electrical quantities, which was installed on generator 1 in the Peruca HPP, was conceived in the first step as a basis for research and development of a method for determining the load angle in stationary and transient operating modes of generators in real operation. The development of a system for determining the load angle was, therefore, the first goal of the research. There are two reasons for setting this goal: (1) knowledge of the load angle is a necessary condition for introducing a mathematical model into the diagnostic analysis of the generator state and (2) there are no devices for measuring the generator load angle except for laboratory purposes. The second goal that was set, which was the research and development of a procedure for identifying the parameters of the hydrogenerator during operation (on-line), directly depended on the accuracy of the procedure for determining the load angle. During the research conducted within the framework of this project, a special identification procedure was developed that was theoretically tested and compared with similar procedures from the literature. It was shown that the developed identification procedure has some advantages such as greater reliability and less sensitivity to the initial values of the parameters. After the problem of determining the load angle was successfully solved, it was possible to perform some checks in the actual operation of the generator in the Peruca HPP. In this sense, an on-line identification of the synchronous reactance in the longitudinal and transverse axis was carried out for different operating points of generator 1. A procedure for determining the stray reactance of the armature winding during generator operation was also investigated, which is also based on measurements within the framework of the electrical quantity monitoring system. Furthermore, a procedure for on-line identification of the reactance of the substitute network was developed and verified, in the laboratory and in the actual plant of HPP Peruca, i.e. short-circuit reactances on the generator terminals. In the 5th chapter of the study, the mentioned researches are described and the obtained results are presented. Once again, it should be emphasized that these results were achieved thanks to the experimental system for monitoring the electric quantities of the hydrogenerator, which, within the framework of this project, was designed, installed and tested on generator 1 at HPP Peruca. In the 6th chapter of the study, certain proposals are given for the introduction of monitoring of hydro aggregates in the hydroelectric power plants PP HE Jug. These proposals are based on analyses of the status and trends in the development of hydropower monitoring in the world and in our country, but also on the results of research carried out within the framework of this study, namely the scientific project Estimation of variables and parameters of electrical machines.
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.
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.
