Energy Storage-Based Active Support Strategy for Grid Frequency of Grid-Configured Offshore Wind Farms

With the new energy of large-scale grid-connected, the scale of offshore wind farms is also getting bigger and bigger. Offshore wind turbines are difficult to provide frequency support to the grid when they are fed directly via flex, and the weak grid operation capacity will be poor. Therefore, this paper proposes a grid-connected control method for offshore wind turbines based on virtual synchronous generator (VSG) technology. Enable offshore wind turbines with good frequency dynamic response capability and inertia support capability. At the same time, through the configuration of energy storage devices for wind turbines to provide the energy needed to support the grid, grid-configured offshore wind turbines smoothly realize active support to assist the grid-constructing type wind turbine in providing frequency support. Finally, the effectiveness of the proposed control method is verified by simulation using Matlab/Simulink software.

I. Introduction

In recent years, to cope with the global energy shortage, environmental pollution, and other problems, China has also been promoting the low-carbon and cleaner transformation of its energy system. The “14th Five-Year Plan” dual-carbon energy strategy target put forward to indicate the direction of China’s future power construction and development planning: gradually reduce fossil fuels’ utilization, increase the scale of construction of new energy sources, such as wind power generation, and the establishment of new energy-led new power system. Wind power is the implementation of the “double carbon” goals and tasks, continues to optimize energy structure, and accelerates the transformation of energy green and low-carbon important direction. The progression of offshore wind power is significant to constructing a strong marine country [1]. In building a new power system with new energy as the main body, offshore wind power is an important part of the wind power resources. Compared with land-based wind power, offshore wind power does not take up land, and is close to the load center, etc. It has become a hotspot for the world’s countries to lay out and compete for development. The market for offshore wind power has added 13.5% from 2021. 50.3 GW of offshore wind power is expected to be added by 2023 [2].