逆变电源（inverter interfaced distributed generation，IIDG）受并网要求控制策略影响对外可等效为受控电流源，导致其故障后内阻抗不稳定，令工频变化量距离保护在IIDG并网环境下适应性差。为解决该问题，深入分析了工频变化量距离保护在IIDG并网侧适应性差的原因，并基于控保协同的理念，提出了一种正序故障分量电流抑制策略，短时将IIDG并网工况下的故障分量网络恢复至近似于同步发电机作用下的无源网络。PSCAD/EMTDC仿真结果表明该策略能够令工频变化量距离保护可靠区分区内外故障并提高其抗过渡电阻能力，极大地提升了工频变化量距离保护在IIDG并网工况下的动作可靠性，且能在很短的时间窗内实现控制目标，保护达到出口条件即可恢复常规的IIDG故障穿越控制，不影响其故障期间的并网能力。

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.