Inverter interfaced distributed generation (IIDG), influenced by grid connection requirements and control strategies, can be equivalently represented as a controlled current source externally, leading to unstable internal impedance after faults and resulting in poor adaptability of power-frequency variation distance protection in IIDG grid-connected environments. To address this issue, the reasons for the poor adaptability of power-frequency variation distance protection on the IIDG grid side are thoroughly analyzed. Based on the concept of coordinated control and protection, a positive-sequence fault component current suppression strategy is proposed. This strategy temporarily restores the fault component network under IIDG grid-connected conditions to a passive network similar to that under the influence of synchronous generators. PSCAD/EMTDC simulation results demonstrate that the proposed Strategy enables power-frequency variation distance protection to reliably distinguish between internal and external faults while improving its tolerance to fault resistance. This significantly enhances the operational reliability of power-frequency variation distance protection in IIDG grid-connected scenarios. Moreover, the control objective can be achieved within a very short time window. Once the protection meets the tripping conditions, the conventional IIDG fault ride-through control can be restored, ensuring no impact on its grid-connected capability during faults.