Research On Modeling And Frequency Control Of The Wind Power Mircogrid

Along with the highlight of environmental degradation, the global energy problem has become increasingly serious. So some clean, cheap, pollution-free renewable energy gain more and more attention of people. How to integrate renewable energy electricity into people’s needs and how to work with the traditional power grid in parallel is a key to the use of development of renewable energy problems. Integrating distributed generations supply and load together, the micro grid, which can not only work as a lonely island but also work with the traditional power grid in parallel, can greatly reduce people’s energy problem. As a result, the development of micro network is a new direction in the development of power grid.Microgrid has two operation modles: the island operation mode and the parallel operation mode. When running in the parallel operation mode, it can accept frequency and voltage support from the power grid.At this time,the operation control is relatively simple. However, when it runs in the island mode, without the support from the power grid, how to keep its frequency and voltage safe is the key to the microgrid. To solve the problem of frequency and voltage when the micro grid work in the island mode,this paper conducted the following research work.(1) Three kinds of modeling for micro sources are built. It use DIgSILENT/Power Factory simulation platform to make modeling of three kinds of micro sources, including wind power generation system, battery energy storage system and diesel generator set.(2) It makes systematic analysis and conclusion for the control strategy of micro sources and microgrid. Comparions and summaries are made of realization method, application condition, advantages and disadvantages of different control strategy. Due to its low capacity and weak inertia, virtual inertia control strategy is raised.(3) It make simulations and analysis for the control strategy of the micro grid which is presented in this thesis. At first,it build the overall model of the micro grid. Then simulation examples are designed. In the end, it used the simulation examples to verify the correctness of the control strategy proposed in this paper.