Abstract: The grid connection of doubly-fed induction generator（DFIG）leads to the reduction of system

equivalent inertia and primary frequency regulation capacity. With the increase of DFIG grid connection scale，the

problem of system frequency regulation becomes more and more serious. In view of this problem，frequency

control strategy of DFIG based on rotor kinetic energy and distributed energy storage was proposed. Through the

quantitative analysis of rotor kinetic energy's frequency regulation ability，it was determined that rotor kinetic

energy and distributed energy storage device were jointly used as the energy source to support DFIG converter

frequency regulation，so that they can respond to the frequency change rate and the frequency deviation

respectively，provide inertia support and primary frequency regulation. The strategy can not only effectively avoid

frequency secondary drop phenomenon，but also make full use of DFIG energy and reduce the distributed energy

storage device's capacity. After that，the capacity of distributed energy storage device was configured from the

aspects of function and power adaptation，then the economic benefits of the proposed scheme were compared with the overspeed load shedding strategy. It was found that the average annual investment cost of the proposed scheme is far less than the economic loss of the overspeed load shedding strategy. Finally，the proposed strategy was verified in Matlab simulation system and DFIG experimental platform. The experimental results show that the proposed strategy can effectively respond to system frequency fluctuations and provide dynamic active power support.

      Key words: doubly-fed induction generator（DFIG）；distributed energy storage device；rotor kinetic energy；

frequency regulation