Operation And Control Simulation Of A Novel Double Fed Induction Generator With Energy Storage

For the influence of energy crisis, the development of wind power generation must beset out immediately. Since the abnormal disconnection of wind turbine in large scaledomestically has taken place repeatedly in recent years, the research on the reliability ofwind turbine connection to the grid is of great significance. The way to use energy storagedevice to improve the performance of the grid-connected wind turbines is an effectivemethod.In this paper, a full scale time domain model for the operation and controllingsimulation of a novel doubly-fed induction generator with energy storage (DFIG/E) hasbeen established. It mainly aims at restraining the wind power fluctuations, and acts as anassistance to improve the ability of LVRT as well as grid integration capability in thecondition of week electrical connection. The main research work includes:Firstly, by simulating the practical generations in the operation states such as constantvelocity at low wind speed, maximum wind energy capture, constant velocity and power athigh wind speed the effectiveness of the model is Validated.Secondly, regarding the restraining0.01Hz~1Hz wind power fluctuations as thecontrol objective of the DFIG/E, two control strategies, i.e. first order smooth filteringmodel and constant grid connected grid power mode, are introducd. The effectiveness ofsmoothing wind power fluctuations with either strategy is analyzed through simulating. Theillustrative comparison of the demand in energy storage capacity is given as well.Finally, this paper researches on the characteristic of connection of the DFIG/E tothe grid. It proves the effectiveness of energy storage which improves the property ofLVRT and the ability of generation grid-connected in the condition of week electricalcontact, coming up with the conclusion that it does not exist the coupled oscillations inlarge wind turbines unit.