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The increasing global energy and environmental problems are encouraging to the development and utilization of renewable and clean energy in various countries. Wind power is one of the major source in large-scale renewable energy applications. However, the frequency regulation becomes a critical issue while the technology is spreading. Research on the frequency modulation (FM) technology of wind turbines and its control strategy for future power grids become significant. The paper proposes a novel coordinated frequency control strategy with the synchronous generator to solve the unmatched state between the output power of the doubly-fed wind turbines (doubly-fed induction generators) and the grid frequency, combined with the frequency response characteristics of the synchronous generator. The FM coordination strategy is formulated by the modulation coefficient from current wind speed and operation mode of each wind turbine. By coordinating the FM output of the doubly-fed wind turbine and the synchronous generator within the allowable range of frequency deviation, it will achieve the dual goal of reducing the frequency regulation pressure of the synchronous generator and indirectly reducing the abandoned wind volume of the wind turbine. The simulation is carried out on the MATLAB/SIMULINK platform. The results show that the presenting variable coefficient frequency modulation strategy could significant smooth the wind power fluctuation, and allow the reserve power of the doubly-fed wind turbine can fully engaged in frequency modulation which will reduces the frequency modulation pressure of the synchronous generator in the system. [ABSTRACT FROM AUTHOR]

The existing virtual inertia control increases the system's moment of inertia, which is beneficial to reduce the short-term frequency drop, but has no supporting effect on the steady-state frequency, and the fan is likely to cause negative power penetration of the system during the recovery of kinetic energy after discharge, resulting in a frequency twice. collapse. In order to realize the transient control performance of grid transient and steady-state frequency under high-permeability wind power, a robust integrated frequency response model with virtual inertia support and steady-state frequency secondary support is constructed. The model includes wind-fire with high wind penetration rate. The bundled DC delivery system and the 500 kV large-scale transmission grid with wind farms control the power contribution of the fan at different time scales with the system frequency change rate. The additional frequency secondary support control strategy establishes the wind speed and the virtual inertia of the fan. The relationship between the coefficient and the system frequency sensitivity function, the dynamic response system steady-state frequency requirement, the wind turbine is introduced into the wind farm virtual weight coefficient after the primary unit of the synchronous unit, and the stratified and step-by-step normal operation mode is provided to provide the transient/stable for the grid. Dual frequency support at full time scale. Based on PSCAD software, a robust integrated frequency control hardware-in-the-loop simulation platform is built to verify the correctness of the proposed method and analysis conclusions. [ABSTRACT FROM AUTHOR]