Analysis of synchronization performance in redundant networks for substation automation

In modern real-time Ethernet networks for substation automation, several protocols are adopted to guarantee the strict synchronization and availability requirements imposed by applications. The management of these networks is more and more complex, since several (cross-influencing) configuration parameters affect the performance of the overall system. In this paper the attention has been focused on synchronization systems applied to redundant network infrastructures for substation automation: in these systems the reconfiguration of the network after a fault may affect the synchronization performance of the nodes. As a test case the SNTP (Simple Network Time Protocol) synchronization has been simulated (with different fault conditions) using two network topologies typically adopted in Substation Automation Systems: RSTP (Rapid Spanning Tree Protocol) and PRP (Parallel Redundancy Protocol). The performance of the two cases has been compared by means of suitable metrics: PRP, as opposed to RSTP, guarantees seamless synchronization performance in case of a single fault.