Pilot protection schemes over a multi-service WiMAX network in the smart grid

Pilot protection schemes, extensively used in high voltage transmission grids, are one of the most effective methods of protecting networked distribution lines that use high speed inter-relay communications for fast fault detection and isolation. This paper examines the use of an IEEE 802.16/WiMAX based wide area smart grid communications network to support such schemes in the smart grid. The IEC 61850-90-5 based routed GOOSE (R-GOOSE) protocol was considered for the high-speed, peer-to-peer communication among the relays. The paper particularly investigates the radio resource scheduling issues for such event-driven, machine-to-machine (M2M) communication traffic over a multi-service WiMAX network. A new QoS scheduling service called `Expedited Effort (EE)' is proposed that uses a fast bandwidth request and a prioritized grant mechanism to transfer the time-critical pilot signals. Simulations were conducted using an OPNET simulation model to analyze the performance of the pilot protection traffic under both the conventional Best Effort (BE) and the proposed EE services. The initial results indicate that the proposed EE service is able to transfer the pilot signals within a guaranteed delay bound as opposed to the conventional BE service.