The offshore wind farms（OWF） with abundant wind energy have received widespread attention recently

and the voltage source converter based high voltage direct current（VSC-HVDC） connection is an effective way to integrate large-scale OWFs. With the increasing penetration rate of renewable energy such as offshore wind power

the frequency stability problem has gradually become prominent. Therefore

the active frequency support schemes for VSC-HVDC integrated OWFs should be proposed to alleviate the frequency stability problem. To this end

this article summarizes the participation of VSC-HVDC integrated OWFs in frequency support control from three levels and analyzes different control schemes: the OWF level

the HVDC level

and the coordination of the two. The principles

advantages

disadvantages

and development trends of the existing strategies are studied

and the conclusion is drawn that the OWFs should coordinate with the VSC-HVSC for frequency support. Then

based on the existing research

this paper analyzes the challenges faced by VSC-HVDC integrated OWFs participating in frequency support. Finally

based on these challenges

this paper summarizes and looks forward to the future research directions in this field. This review has certain reference value for the participation of VSC-HVDC integrated OWFs providing frequency support and the realization of dual-carbon goals.