Research Of Transient Model And Stability Analysis Methods For Wind Power Generation Units

Recently, due to the incremental rate of environmental concern, wind-energy development has experienced a significant of interest and considerable attention all over the word. Large wind turbines with the rated power of MW levels are becoming more and more attractive to offshore wind farm, and a number of wind farms of rated capacity of hundreds of MW levels are going to be connected with the existing power system in the near future. Due to its simple construction and low maintenance cost, wind turbines based on induction generators are mostly used. The increasing levels of wind-energy generation will promote an important demand to evaluate their impact on the transient stability of the electric grid. Therefore, it is essential to investigate the suitable and valid transient models of wind generator systems to assess the transient stability of wind farms and their impact on the connected electrical transmission systems.The transient stability principle of double-fed induction generators was analyzed. A 6×1.5 MW single-loop system of double-fed induction generators were built. Based on the wind turbine models, the dynamic behaviors were simulated and compared using Matlab/Simulink, under the generators were subjected to small signal stability or transient stability, and compared with their voltage regulation control and var regulation control. Then, the double-fed induction generators and the squirrel cage induction generators were subject to a 3-phase short circuit fault in different systems of same conditions, analyzed the wind turbine model of transient stability form the System access and network stability. Results show that the doubly-fed induction generators in a small interference can regulate power factor, voltage stability. And has a better stability than the traditional wind turbine in large interference.