Study On Subsynchronous Components Propagation Path And Disturbance Source Location Of Wind Power Collection Areas

With the large-scale wind power integrated to the weak power grid,the risk of subsynchronous oscillation is worthy of attention in the process of safe and stable operation of the renewable energy transmission system.In order to analyze the subsynchronous oscillation in the wind power collection areas,it is very important to study the propagation path of subsynchronous components and propose the method to locate the disturbance source.The main contributions of this thesis are summarized below.(1)An operation parameter model of synchronous generator,transmission line and permanent magnet direct driven wind turbine is deduced.The mathematical model of synchronous generator,transmission line and other system components is deduced in synchronous coordinate,and considering the influence of d-q axis coupling and grid side control strategy,the operation parameter model of grid connected inverter including direct voltage capacitor and filter circuit is established based on the small signal analysis method.(2)An analytical method is proposed to analyze the propagation path of subsynchronous components of wind power collection areas based on the parameters of synchronous coordinate.The influencing factors of the propagation path such as inject frequency and inject position are analyzed in AC system by using shunt coefficient method.And the subsynchronous components propagation path of the subsynchronous oscillation happened in wind farm integrated to the power grid is analyzed by this method under the unified coordinate system.The validity and applicability of the shunt coefficient method to analyze the propagation path in the renewable energy integrated area is proved by time domain simulation.(3)A propagation path matching principle is proposed to locate subsynchronous oscillation disturbance sources of the multi-wind farm integrated to power grid.The propagation path of subsynchronous current in the system when subsynchronous oscillation happened in different wind farms is calculated by analytical calculation.The actual propagation path of subsynchronous current in the system when subsynchronous oscillation happened is obtained by the monitoring device in this area.The principle of path matching is applied to determine the dominant wind farm which caused subsynchronous oscillation,so that the disturbance source can be located.