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重复控制的高增益特性可以提高并网逆变器的并网电流品质，但电网频率波动对系统的跟踪精度会产生较大的影响。在传统重复控制中，通过引入系数 Q 可以提高内模的稳定性。该文分析了引入内模系数 Q 后的重复控制与准谐振控制的等效关系，证明了引入内模系数 Q 可以在一定程度上提高重复控制对电网频率波动的适应能力。通过对LCL型并网逆变器重复控制的稳定性分析，得到重复控制增益系数Krc的设计方法，解决了由于内模系数Q较低导致的重复控制增益不足的问题。仿真与实验表明所提出的重复控制器对电网频率波动具有良好的抗电网频率波动能力。“,”Repetitive control which produces high gains, can improve current quality of grid-tied inverter. However, the tracking accuracy of the system degrades because of grid frequency variation. In classical repetitive control, a parameter Q is proposed to improve the stability of internal model. The equivalent relation between the repetitive control with internal model parameter and the quasi-resonant controller was analyzed to prove that the internal model parameterQ could improve the adaptability of the repetitive control to the grid frequency variation to a certain extent. By analyzing the stability of LCL-type inverter with repetitive control, a design method of repetitive control’s gain parameters was proposed, which solved the low-gain problem caused by the internal model parameterQ. Simulation and experiments show that the proposed repetitive controller has good ability against variation of grid frequency.