There are obvious defects in the traditional HVDC technology in power regulating speed,reduce the loss,protection and control,has been unable to meet the electricity demand diversity.Emergence of VSC-HVDC not only solves the defects,but also has the power of independent controllable and has the advantage to supply power to a passive network etc,widely used in power generation,new energy and other fields of distributed micro grid.In this paper,double end DC is taken as the research object,and the mathematical model of both ends flexible and straight is set up.On this basis,the basic operation mode of the system and the control strategy of the voltage source type (VSC) converter are studied.Considering the control delay of the VSC converter and the poor responsiveness of the current closed loop control,an improved deadbeat control strategy is proposed to solve the above defects by predicting the k+2 time sampling current.Finally,the correctness and reliability of the above methods are verified by CO simulation.