PROTECTION AND CONTROL INTEGRATION, NUMERICAL RELAY PROGRAMMING AND INTEGRATION, COMMUNICATION PROTOCOLS
When helping a client select protective relays, communication protocols and communication backbone, several things need to be considered. PCE listens to the clients and gives recommendations based on available budget, system scalability and upgradability, client’s expertise and communication availability. We also attempt when possible to give our clients options and then enter into discussions of pros and cons of the manufacturer’s equipment available and the technology.
For the vast majority of the hundreds of substations PCE has designed, our services included the design of the protective system. In our early years we gained vast experience with many electromechanical relays. In the more recent years we have done these same protective schemes with more modern microprocessor based relays and implemented more advanced schemes such as bus diffs with no CTs. With these modern relays we have been able to implement smart grid designs that combine the protection with control for the smart grid. With these numerous smart grid applications, PCE has gained experience in the use of DNP3, ACS, QEI, and Cooper 2179 protocols, including setup and troubleshooting of communications issues. The options for the communication backbone continue to evolve. In our early installations of smart grid, most communication was done over radio or microwave. PCE has communications system design and startup experience with leased telephone, frame relay, serial 900 MHZ licensed and unlicensed radio, and TCP/IP over Ethernet for SCADA master to RTU/gateway communications. We are seeing more and more applications using Ethernet and fiber optics.