Large scale fluctuation of wind energy power may lead to system frequency fluctuation because of the shortage of traditional frequency modulation resources in an isolated power system with high permeability access. This limits the further access to new wind energy power. Hence, this paper presents a frequency coordination control method of a variable speed wind turbine based on inertial and droop control. First, the frequency control characteristics of three types of Variable Speed Wind Turbines (VSWTs) are analyzed, including those of a Doubly Fed Induction Generator (DFIG), a Permanent Magnet Synchronous Generator (PMSG) and an Active Stall Induction Generator (ASIG). From this, a frequency coordination control strategy of a variable speed wind turbine based on inertial and droop control is proposed, and the influence of different inertia and droop parameters on the frequency of isolated power system under different disturbance conditions is analyzed. From this, the appropriate control parameters can be selected. Finally, the steady-state and transient responses of wind turbines are simulated under the condition of random wind speed disturbance and large disturbance, and the effectiveness of the proposed frequency suppression method is verified. The results show that the proposed method can significantly improve the frequency stability of an isolated power system. This work is supported by the National Natural Science Foundation of China (No. 61963020) and the Science and Technology Project of Yunnan Power Grid Company: Yunnan Power Grid Stability Control Technology Research and Closed Loop Simulation Platform with Multiple DC and High Proportion of New Energy (No. KJDK2018210).