RPR-based PPS distribution scheme for protections in distribution networks with DGs

According to the requirement for a protection scheme based on synchronized phasor measurement in distribution networks with distributed generations, a RPR-based PPS distribution scheme was proposed. In this scheme, reserved control code group K28.6 in Ethernet physical coding layer is used as PPS positive edge transferred with preemptive priority in both ringlets of RPR. And a compensation algorithm is applied to balance out the propagation delay. And tolerance analysis and hardware design were presented in the paper. Simulation results indicate PPS distribution precision is up to nanoseconds level. The scheme enables the merger of both communication network and PPS synchronization network.