Modeling Studies Of Main Generator Excitation Systems In The Power System

With the rapid development of social economy, the development of national power grid has entered a period of rapid development. These have a great impact on the safe operation of the power system. Therefore, it is significant to study the generator excitation system modeling, in order to keep the stability performance of the synchronous generator to the safe and stable operation of the whole power grid. However, due to the actual operation of the power system, the model is often inaccurate, lack of parameters and other issues. So it is very important to set up the model of the main generator excitation system, to test and check the parameters in order to get the model and parameters of the power system and to establish the model database of the excitation system.First of all, in the previous period technologic method of generator excitation systems modeling were studied. It includes the selection of P.U, the modeling studies and testing parameters of excitation components, and identification method study. Secondly, the process of excitation system modeling studies in a great turbine generator and a great hydraulic generator are illustrated. The studies as follows are information collection, theory analysis, compiling test scheme, on site test, parameter estimation and model identification. Through different identification method used on generator different operation state, the exact fit fact models and parameters of excitation system were established. Furthermore, the Real-Time Digital Simulator System was successfully used in the excitation system close-loop test on site. The RTDS used in this domain of excitation system is in the lead of the countrywide Electric Power System. Finally, on the base of excitation system modeling, the single-generator to infinite-source simulation model was established in the RTDS system. Then the check tests were stimulated under generator no-load and load conditions. The result is that the models and parameters identified from generator excitation system are basically exact. In addition, after comparing the site test waves with the RTDS simulation waves, the variable range and regulating time are ultimately accordant. And the PSS has the effect on restraining generator active power swing under load step response test and line operation switch test.Contributing with the study of system identification theory, author adopted different identification methods in the site tests. The feasibility of frequency-domain approach and time-domain approach were validated. They provide different test methods for the technologic item of generator excitation system modeling. After parameter estimation from site test data, the database of excitation system models was established which settle for all kinds normal requirement. It will be used in Fujian power system analysis(including PSASP, BPA, PSS/E program etc), RTDS simulation research and test research of excitation system. In conclusion, the result of modeling study in main generator excitation systems signifies to improving safety, economy and stability in Fujian power system. Also it provides reference to RTDS application and exploitation in country.