Modeling and Performance Analysis of Data Flow for HSR and PRP under Fault Conditions

To ensure reliability and availability of IEC 61850 based substation automation systems (SAS), High-availability Seamless Redundancy (HSR) or Parallel Redundancy Protocol (PRP) or both are used. This paper presents the analysis and comparison of the device connection capability and data recovery time performance for HSR and PRP networks. An IEC 61850 based substation with both HSR and PRP bays is designed and modelled using the OPNET. The device connection capabilities, e.g. the maximum number of devices that can be connected to a fixed bandwidth network, under various operating conditions are evaluated and studied. A comparison study between an HSR network and PRP network has also been carried out. The results show that the device connection capability of an HSR network can be reduced by as much as half as each packet is duplicated in the HSR network. The results also show that the Ethernet bandwidth utilization is decreased as the number of devices increases. The work may help utilities to determine the number of devices that can be connected into an HSR/PRP process bus network in order to ensure the network performance.