Generally, the wind-power output fluctuation is compensated by a rather large capacity battery system. In order to reduce the capacity of the battery, long term fluctuation component should be reduced. We have proposed a hybrid generation system which is composed of large scale off-shore wind farm with small scale tidal generation system (HOTT; Hybrid Off-shore and Tidal Turbine). The basic concept of HOTT generation system is to compensate wind power fluctuation by controlling the output of tidal generation system. If the tidal power compensates some long-term portion of the wind fluctuation, the battery capacity can be reduced. In this study, for coordinating compensation by the tidal generator and the battery, a control system was designed limiting compensating frequency range by using band pass filter and phase compensation. The characteristics of this system was investigated by simulation studies.