Gird frequency deviation can be improved through short-term active power support from grid-connected doubly-fed induction generators(DFIGs)with inertia control. Based on the analysis of mathematical model and control strategy of DFIG

a simplified model of DFIG incorporating the inertia control is developed. Through the quantitative definition of equivalent inertia time constant

the ability of DFIGs to provide inertial response can be evaluated. By applying the slip control strategy in the vector control frame

this paper proposes a slip-feedback inertia control strategy which uses generator slip as a control variable. Finally

the simulation model is developed on DIgSILENT. Simulation results show that the proposed strategy can significantly reduce the frequency deviation caused by load fluctuation

with the advantage of accelerating the recovering speed and mitigating the adverse impact of speed recovery on gird frequency.