In order to solve the problem of excessive damage to doubly fed induction generator（DFIG） system under unbalanced voltage

and to achieve the three different control objectives of eliminating the second harmonics of grid-side active

reactive power

and the negative sequence component of the grid-side current

we proposed a DFIG grid-side converter（GSC） control method based on internal model observer and passivity-based control.And then

according to the uncertain factors such as the parameter perturbation

interference of the current loop in the controller

a state observer based on internal model control（IMC） is combined with passivity-based control

to realize the control of current compensation is proposed

which can reduce the current steady state fluctuations

and observer parameters are optimized by pole placement method.Finally

the results of Matlab/Simulink software simulation and hardware experiment show that the proposed control method

of which coordinated controller of PBC and IMC is used in its inner loop

and PI controller is used in its outer loop

has the advantages of simple structure

fast response speed and strong robustness

compared to the double closed PI controll method.