Types of Communication Protocol Standard for Substation Automation

Communication protocols are the most critical and important parts of power system operations in transmitting and receiving information from different levels of a substation. Despite its significance, until now, communication protocols are rarely incorporated with cyber security and security measures against disturbances and power and equipment failures. These threats are common to different communication protocols if the transmission of data is unsecured. Power utilities now clearly understand the risks and chaotic results of unsafe data. Figure 1 illustrates the evolution of most common IED communication protocols that are widely used in the substation environment. These are the Modbus, Distributed Network Protocol 3 (DNP3), IEC 60870, Utility Communication Architecture (UCA) and the IEC 61850 [6].
• Modbus – Master / Slave protocol (Request/Reply)
• DNP3 – widely used in North America and uses Master / Slave protocol
• IEC 60870 – widely used in European countries for SCADA, etc.
• UCA - Basis for IEC 61850
• IEC 61850 – Communication protocol for substation automation