Overcurrent Relay Advances for Modern Electricity Networks explores how to optimize protection and improve system stability and resilience by implementing advanced overcurrent relays in highly dynamic renewable heavy power systems. This guide provides a foundation in relay functions and behaviors in current modern networks, particularly regarding renewable power sources and new electrical network structures such as microgrids. The work discusses the design and creation of protection schemes in smart grids and analyzes their impact on performance and security in protection systems. This practical book also presents a critical new coordination method for online applications.