The DC voltage stabilization is vital precondition of voltage sourced converter based multi-terminal high voltage direct current（VSC-MTDC） transmission systems. We analyzed the operation characteristics of droop control strategy used in VSC-MTDC

and proposed an improved method of control strategy. The improved control method works by measuring DC voltage to feedback to revise droop slope. This new control method is reliable and can simplify the design of controllers. Moreover

we analyzed the control characteristics of the new method and proposed a coordinate control strategy. Theory analysis indicates that when small variations occur

the new method can reduce DC voltage deviation;when serious large faults occur

the improved method can keep converter in operating in safe section. Finally

a typical 4-terminal VSC-MTDC transmission system in PSCAD is taken for example to verify the effectiveness of the proposed method.