The aim of relay coordination is to obtain the optimal relay settings which result in minimum operating times of the relays, satisfying selectivity constraints. In combined coordination of distance and overcurrent relays (D&DOCRs), operating times of the second zone of distance relays (TZ2) are typically increased in order to satisfy the selectivity constraints. In this paper, a new operating characteristic (OPC)for distance relays is proposed which decreases TZ2 s. In the proposed OPC, the common characteristic for the second zone is divided into two sections: the first section protects the main line beyond the first zone with delay time TZ2n1 , and the second one protects 50% of the adjacent line with delay time TZ2n2 . A new formulation is then proposed for the nonlinear problem of D&DOCRs coordination based on the proposed OPC. The presented method is tested on three test systems, namely the 8&bus, the IEEE 14&bus and the IEEE 30&bus test systems. The simulation results show that the method can be used to achieve a faster protection especially when robust coordination is desired

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