Abstract：Since the compressed air energy storage system grid-connected inverter voltage is always influenced

by voltage fluctuations of the power grid with little problem，for the sake of ameliorating the dynamic and stable

performance of the DC bus voltage of the inverter on the side of the grid and the actual output power of the system

in the compressed air energy storage expansion power generation system and reducing the fluctuations，secondorder linear active disturbance rejection control（LADRC）technique was used in the voltage outer loop control，a new-style double closed loop control construction was formed. The mathematical model of the grid-connected converter of expansion power generation system was established，the operating principle of LADRC was

researched，and the conventional PI control was contrasted with the control methods studied. The simulation results

indicate that when make a contrast with the conventional control methods，the control methods designed can make

the DC voltage enter the stable state more quickly，the total harmonic distortion（THD）of the grid-connected

current becomes smaller，and has better disturbance immunity.

      Key words：compressed air energy storage；grid-connected inverter；DC bus voltage；linear active disturbance rejection control（LADRC）；immunity to disturbance