Concerned with the high frequency problem existed in isolated Zhaoyang grid which is mainly caused by the point-to-grid transmission mode of No.3 Manasi power plant, a new high frequency control scheme and the relevant control policy is proposed with detailed analysis and comparisons between the effects of other existing control methods. The proposed scheme can solve the high frequency problem of Zhaoyang isolated grid, and also can avoid the problems such as synchronization between different systems as well as the voltage loss problem of 220 kV bus so that it also provides a new way for solving similar high frequency problem under point-to-grid transmission mode.