Overcurrent relays (OCRs) coordination in the distribution network have become a complex issue due to the integration of distribution generations (DGs) using various technologies. The uncertainty associated with the connection and disconnection of the renewable energy sources in the distribution network, along with changes in short-circuit currents, may disturb the coordination of the OCRs so in such cases, the backup relay malfunction causes more consumers to outage. This paper investigates the impact of the photovoltaic (PV) unit outage on the performance of overcurrent relays with different characteristics and a normally inverse, definite time, instantaneous curve is proposed to address this uncertainty. The proposed curve is designed in such a way that it ensures the coordination of overcurrent relays under various fault conditions, even in the presence of PVs uncertainty. PV penetration doesn\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'t affect the proposed method and also it applicable to mesh and radial networks. The method is applied and evaluated on IEEE 14-bus and IEEE 33-bus standard systems. The results demonstrate that the proposed method successfully reduces the relay operation time while also ensuring adherence to all coordination constraints, without any violations.

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