SYSTEM PROTECTION SCHEME

摘要

The present invention discloses a system protection scheme comprising of at least three system protection terminals (18), introduced at suitable locations in an electric power system (1). The system protection terminals (18) are interconnected by a communication system (22), using a substantially dedicated communication resource. At least two of the system protection terminals (18) are equipped to collect measurement signals (72) associated with characteristics of the power system at that particular location. The measurements preferably comprise complex ac quantities and stability indicators. The signals are processed and data related to the measurements are spread on the dedicated communication resource to the other system protection terminals (18). At least two of the system protection terminals (18) are equipped to evaluate the condition of the associated part of the power network and if necessary provide control signals (74) to power system units. The evaluation is based on selected parts of the data available on the communication resource and locally available data.