| Since the "double carbon" goal was proposed,how to transition the power system from the traditional energy structure to a new energy structure based on renewable energy generation has become a hot topic of current research.Among them,wind power has achieved large-scale access to the grid with the advantages of mature technology and lower cost,but wind turbines generally operate in the maximum power point tracking mode can’t participate in the system frequency regulation process,so the high proportion of wind power penetration in a certain degree weakened the power system inertia and frequency regulation capacity,therefore in high wind power penetration system in wind turbines reserved part of the active power participation in the system frequency regulation process is conducive to improving the system frequency support capacity.On this basis,large-scale energy storage is widely used in inertia support and frequency regulation of power grids due to its rapid response and stable output.In order to reduce the negative impact of wind power grid connection on the power system,this paper proposes a frequency modulation method for coordinating wind turbine and energy storage by considering the frequency support capability of the system,and achieves the optimal configuration of control parameters for the energy storage system under this strategy.First of all,this paper establishes a virtual synchronous machine control model for wind turbine rotor over-speed control and energy storage system,and determines the frequency modulation control strategy for wind turbine and energy storage system to participate in grid inertia and frequency support.Taking the rated rotational speed and active output of the doubly fed wind turbine as constraints,the optimal power reserve factor is set based on rotor over-speed control to divide the wind speed range for the wind turbine to participate in system frequency modulation.On this basis,considering the system frequency support capability,a frequency modulation method for coordinating wind turbine and energy storage system is proposed,which realizes the coordination between wind turbine and energy storage system in the process of system inertia support and primary frequency modulation.In addition,based on the consideration of the dynamic frequency dispersion of the system,the installation location of the energy storage system is determined.Four relevant evaluation indicators are cited to analyze the impact of different control parameters of the energy storage system on its dynamic frequency regulation characteristics,and three quantitative indicators are used for detailed comparative analysis.This determines the prerequisite for optimizing the configuration results of the energy storage system.Subsequently,through the analysis of the energy storage active power output and the steady-state recovery process of the system,the dynamic frequency regulation characteristics of the energy storage system under the virtual synchronous machine control strategy are depicted,thereby achieving the optimal configuration of control parameters for energy storage under different operating conditions and support requirements of the system.Finally,the proposed method is simulated and validated using DIg SILENT/Power Factory.The simulation results show that the proposed method can fully utilize the wind power’s own frequency modulation capacity while ensuring the system’s frequency modulation requirements,optimize the configuration results of energy storage system parameters,achieve smooth output of energy storage output,and improve the frequency support capability of the system. |
PDF Full Text Request