Implementation and Operational Experience of a Wide Area Special Protection Scheme on the SRP System

As the existing transmission system infrastructure is challenged to support loads beyond original design limits, the implementation of "wide area" power system protection systems (PSPS) are often needed to maintain transmission system integrity. Such a system, with stringent performance and availability requirements, has recently been designed and installed on the salt river project (SRP) system. In particular, measurements of generation levels on one side of the system must affect load balance on the other side of the system over 150 miles in less than 1 second. This paper starts by presenting the need for the PSPS and the resulting design requirements. It then discusses the architecture that resulted from the requirements and the subsequent implementation and testing issues. Actual operation and performance results, including end-to-end timing tests, will be presented. The paper concludes with a discussion of desired improvements in the architecture and new solutions that are available through the generic object oriented substation event (GOOSE), virtual LAN (VLAN), and priority messaging technologies that are now available through the IEC 61850 communication protocol