For more than 100 years power systems have been constantly evolving and recently the pace of their development is only growing. Despite of such rapid modernization relay protection systems still play a key role in providing their reliability. Global changes in power industry, such as: implementation of intelligent electronic devices, development of smart grid networks, DER deployment, introduction of FACTS and wide implementation of electric vehicles lead to the inevitable complication of design, operational management and relay protection operation systems tasks. According to North American Electric Reliability Corporation statistics, up to 70% of large-scale failures and major accidents in power systems occur due to its incorrect operation.
