Abstract: This paper explores insufficient linear change sensitivity of VDCOL（voltage dependent current order limiter）and unicity of PI controller parameters in the CIGRE HVDC Benchmark Model as proposed by CICRE. Using the idea of fuzzy control,PI and VDCOL are improved into the fuzzy control controller by taking the error and error deviation as the input of fuzzy control,and the output control signal after fuzzy reasoning and refinement. After the fuzzy control rules are realized by fuzzy toolbox of MATLAB,they are applied to the HVDC standard test system. After simulating with MATLAB/SIMULINK in three working conditions,such as normal working condition,singlephase grounding fault and three-phase grounding fault,and comparing the DC voltage,DC current and turn-off angle at the midpoint of the DC transmission circuit,the simulation conclusion is drawn: under the combined control of fuzzy VDCOL and fuzzy PI, the continuous commutation failure can be effectively suppressed;and the recovery effect is better than that of the traditional control after the inverter fails.