In order to improve the virtual inertia of the energy storage and stability of power systems, an inertia lifting method of an energy storage converter based on secondary system optimization is proposed. A complete state space model of the energy storage converter is built, the dynamic performance of system with different controller parameters is analyzed, and oscillation characteristics of the virtual synchronous machine are revealed. Then a linear quadratic optimal controller based on a state observer is designed and the secondary system of the energy storage station is optimized. The method reduces the adverse impacts of a conventional virtual inertia controller on stability. The accuracy of the proposed state space model and the effectiveness of the controller are verified by the co-simulation of DIgSILENT/PowerFactory and Matlab. This work is supported by the National Key Research & Development Program of China (No. 2017YFB0903400).