Evaluation of the DFIG wind turbine built-in model in PSS/E
Ladda ner
Typ
Examensarbete för masterexamen
Master Thesis
Master Thesis
Program
Publicerad
2009
Författare
Seyedi, Mohammed
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Due to growth of environmental concern, more electricity must be generated from renewable energy sources. One of the most cost efficient alternatives is wind energy. Large wind farms with several hundred megawatts of rated power have been connected to grid. Nowadays, many transmission system operators require wind farms to maintain zero reactive power exchange with the grid during normal operation. Furthermore, like other conventional power plants wind turbines must be able to remain connected to the grid during grid faults. In order to study impact of wind power generation on the power system valid models of wind turbines are needed. The purpose of this study is to evaluate DFIG wind turbine built-in model in PSS/E. In this report, the responses of the model subjected to grid disturbances are investigated. At first, the typical dynamic model of a DFIG wind turbine is introduced. Secondly the built-in dynamic model for DFIG wind turbine in PSS/E is illustrated and it is used to study the dynamic behavior of DFIG subjected to a symmetrical short circuit at the point of common coupling of a large wind farm. The load flow study for a network where a wind farm consisting 67 numbers of DFIG wind turbines and each one with 1.5MW rated power connected to the grid are presented and the output results from load flow study is used to perform dynamic simulation. The voltage, current, output power, speed and pitch angle profiles are presented in the dynamic study. The dynamic simulation results shows that the DFIG dynamic model presented in PSS/E is not able to fully represent the limitations of the wind turbine. There are some deficiencies in the model, for example the protection systems for converter and rotor are not included in the model, under/over voltage protection and rotor current limits are not considered. The upper and lower limitation in the voltage control loop will affect the voltage stability and there is no direct relation between the maximum over load on converters and the limitation in voltage control loop.
Beskrivning
Ämne/nyckelord
Elkraftteknik , Electric power engineering