Analysis for the Improvement of IEC 61850 Based Substation Communications Using OPNET

Electrical substation is one of the most important parts of power system network. Over the years, the substations have undergone several structural and technical modifications. The IEC 61850 standard launched by the International Electrotechnical Commission (IEC) has created a strong platform for modern Substation Automation Systems (SAS) based on Digital Communication Systems. To increase the system reliability and efficiency, the Substation Communication Network (SCN) should have a quicker response, especially during electrical faults. According to the IEC 61850 standard, the end-to-end (ETE) time delay for transmission and control of data has to be less than 4-ms which is achievable when the data packet size is smaller. However, when the packet size is larger, it exceeds the delay time limit. Hence, sending smaller data packets could be a solution, but sending too many smaller packets might create congestion in network incurring another delay issue. This paper presents a different network topology that is designed in Optimized Network Engineering Tools (OPNET) environment which is capable of transmitting and controlling larger data packets within the 4-ms time delay limit as recommended by the IEC 61850 standard.