I. Introduction
With more and more installed capacity of new energy, wind power penetration showed a rising trend year by year[1].Therefore, in the course of wind energy integration, the unit is required to have a certain fault ride through capability to resist the influence of the power grid on the system. It is particularly important to study faults ride through technique of this system, containing low as well as high voltage ride through[2] - [3].Up to now, the low voltage ride through technique developing for new energy units in various countries is relatively perfect and has been successfully used to this actual system. When system completes the low voltage fault, if the system has excessive reactive power compensation after the fault ends, or when the system has commutation failure, blocking and other faults during high voltage transmission, the high voltage fault of the system will be further caused [4] - [5].Therefore, it can be very significant to research this high voltage ride through of new energy units for the stable operation of power grid.