Modeling Of Direct Drive Wind Power System And Voltage Control Strategy Analysis

Wind power generation with its own clean, abundant resources, low cost, has become the focus of the field of the development of new energy and renewable energy. Large scale wind farms based on direct drive permanent magnet synchronous wind power generator is increasing, the voltage stability of permanent magnet direct drive wind farms which connected to the grid is an important issue for the experts.According to the stability problems of permanent magnet direct drive wind farm, Build large scale wind farm which connected to the grid in the DIgSILENT power system simulation software, and from the perspective of small disturbance stability and transient voltage stability, the system is analyzed and studied. Specific research contents are as follows:(1) Introduces some problems of the domestic wind power generation and the status of wind power at home and abroad, moreover, expounds the present situation of related research and the research significance of this topic.(2) Based on electromagnetic transient model with direct drive permanent magnet synchronous wind power system, getting all the eigenvalues of the system by the eigenvalue method. Then keep with the dominant eigenvalue related state variables(the leading state variables) and leave out the other state variables(the non-leading state variables), finally get the reduced order model of direct drive permanent magnet synchronous wind power system electromagnetic transient.(3)Firstly, analyses the small disturbance stability of a simple wind power system, which consists of direct drive permanent magnet synchronous wind generator and infinite bus by eigenvalue analysis method, then the characteristic of modal method (Arnoldi method) is used to analyze the small disturbance stability of wind farm integration system, and by increasing the wind farm capacity,the characteristic modal distribution and the weak stability modal of the wind farm integration system under different capacity are obtained, thereby analyses the small disturbance stability of large scale wind farm integration on power system.(4) Research on grid side converter and put forward voltage control strategy. The reactive power is issued by the network side converter to help restoring the grid voltage.