CONTROL OF PROTECTION RELAY

摘要

A protection relay and a method for controlling a protection relay are provided. An input parameter value is measured for the protection relay, and a calculation parameter value is determined based on an inverse definite minimum time curve defining a relationship between the input parameter value and a predetermined threshold value of the input parameter, wherein the calculation parameter values are divided into two or more zones and restricted with zone-specific dividers. The restricted calculation parameter value is added to a cumulative sum of the calculation parameter, where the cumulative sum of the calculation parameter is usable in a calculation equation for determining an operate and/or reset condition of the protection relay.