Simulation Analysis Of Reactive Power/Voltage Control Of A Wind Farm Based On RT-LAB

Control strategies could be verified and controllers could be tested with hardware-in-the-loop if real-time simulation technology is brought into wind power research field and a real-time simulation platform of wind farms is built up. The wind farm simulation platform is designed and established with RT-LAB based on the mathematical model of wind turbines and wind farms. Reactive power/voltage control strategies of a wind farm are implemented on the platform.1. The dynamic mathematic model of a wind turbine is established, including turbine, drive train, generator, converter, pitch system and crowbar. Control strategies of typical operating conditions such as MPPT, dispatching, grid-connection and cutting-off are proposed. A mathematical model of wind speed based on ARMA, which taking wake effect and time-lag effect into account, and a wind farm model with SVG are also established.2. A wind farm simulation platform is designed and implemented, including general plan, components, communication system, user interface and wind farm simulation models. Then a single wind turbine and a whole wind farm are simulated. The results show that the wind farm model is qualified to implement power control simulation.3. The voltage profile of a wind farm strongly or weakly connected into power grid is studied. Control strategies of voltage at grid-connected point based on SVG or DFIG are designed and simulated. The results show that voltage at grid-connected point maintains within a reasonable range under designed control strategies.