Research On Modeling And Simulation Of Doubly-fed Type Wind Power Generation System Electromechanical Transient Model

As a new type of renewable clean energy, wind power has got wide attention in the field of industry as the main new energy and it is in rapid development. Because of the volatility of the wind and intermittent, along with the expansion of wind farm scale and also the capacity of single unit, the influence to the stable operation of network which contains of wind farms will be more and more big. Therefore, it is necessary to establish an accurate model of wind power generation system for system simulation.This paper takes doubly-fed type wind power generation system as the research object, and focuses on its operation principle analysis, control strategy realization, modeling and simulation of system, etc. The basic theory of each component of doubly-fed type wind power system is introduced detailedly in the paper. The focus of research is the control strategy of converter. A double closed loop decoupling control of the converter is realized by using vector control technique. And models of pitch angle controller and maximum wind power point tracking controller are established. Then, according to the dynamic characteristic of converter, its control systems are simplified reasonably, and mapped detailed structure diagrams.According to the mathematical models and the simplified structure of block diagrams, models are established by using Matlab/Simulink, including combination wind speed, wind machine, doubly-fed induction generator, converter and its vector control system, variable pitch control mechanism and maximum wind power point tracking controller. On the basis of constant network voltage, each component of the system is connected to set up electromechanical transient model of the whole system. Make simulations and qualitative analysis when the actual wind speed is greater or less than the rated wind speed. The simulation results show that the simplified control system model is effective and the whole model is reasonable and correct.On that basis, the electro-magnetic transient model of doubly-fed type wind power system is established using the user-defined function of power system analysis software package (PSASP7.0). Through simulation analysis of time domain on wind farm-infinite system by setting faults including wind speed change and bus faults, it is proved that the model can reflect the transient Performance of network correctly.