Traditional power conversion system control methods, such as grid-following (GFL) control and grid-forming (GFM) control, have problems of insufficient frequency support capability and slow power response respectively in practical applications. To address the above issues, this paper proposes a fast response control method for power conversion systems based on coupled Virtual Oscillator Control (VOC). This method combines grid-following current control with the virtual oscillator, forming a GFL-GFM coupled control model, thus possessing both fast power response capability and steady-state frequency support capability. In this paper, the dynamic response and small-signal model of the proposed coupled VOC are derived and verified by MATLAB/Simulink. The results show that the proposed coupled VOC control method is superior to VSG and independent VOC in terms of power response speed and overshoot control; compared with VSG, the coupled VOC exhibits stronger frequency support capability and faster response speed. The proposed method can provide theoretical and technical references for the engineering application of energy storage converters in new power systems.