In view of stability issue of independent DC micro grid

a kind of current passive double closedloop control strategy based on sliding mode variable structure is proposed

which improves the response speed and anti-interference ability of the system. First

the mathematical model of the independent DC micro grid system is set up. For the model

the control input of the system is designed by passivity theory and the portcontrolled dissipation Hamiltonian with distribution（PCH-D）model of the system is obtained. Then

as for the stability of DC bus voltage of the system

the sliding mode variable structure method is used. In case of sudden variation of electrical load

distributed energy and parameters

the busbar voltage can still stableat its expected value and the reference value of fuel cell current is obtained. Finally

the verification is performed through Matlab simulation. The comparison of the control strategy in this paper and the traditional single reactivepowercontrolshowsthattheproposedcontrolmethodhasbetterdynamicandsteady-statecharacteristics.