Topology, principle and model of wind power flow optimization control system

Wind power flow optimization control system based on the supercapacitor and the battery can smooth the power fluctuation of wind power generation, enhance the capacity creditability and improve the power quality. Firstly, the overall topology and basic idea of wind power flow optimization and control system is analyzed. In the system, a bi-directional DC-DC converter is used to control and distribute energy between both energy storage elements, and a four-quadrant DC-AC converter is used to adjust active power and reactive one injected into the grid. Secondly, working principle of the bi-directional DC-DC converter is described and its linear small signal mathematical model is deduced by virtue of average switch modeling method. Finally, working principle of the four-quadrant DC-AC converter is illustrated and its linear model in the rotating reference frame is constructed. Theses works provide the foundation for the design of control unit of wind power flow optimization control system.