Voltage-sag indices - recent developments in IEEE PI564 task force

The project for developing recommended practice for the establishment of voltage sag indices was approved by the IEEE in January 2000. Since then, the task force P 1564 met twice a year and developed a draft document. This paper presents the current state of discussions and a summary of the latest draft D2. Next to retained voltage and duration, as defined in IEC 61000-4-30, this paper discusses three-phase characteristics, voltage-sag energy indices, SARFI-indices, and voltage-sag tables. Triggering level and time aggregation are also briefly discussed.