Across the various condition monitoring options available for transformer health, Online Dissolved Gas Analysis (ODGA) has become the go‑to early warning system. Yet too often, alarm logic still relies on static ppm thresholds that ignore a unit’s context, leading to nuisance alarms and operator fatigue. We bring you the first part of this article by Bhaba Das and Marius Grisaru, which presents a practical, standards‑aligned methodology moving from fixed limits to transformer‑specific baselines, population statistics, and noise‑robust Rate‑Of‑Change (ROC) and explains how to cut false positives without compromising sensitivity. It draws on advice from IEC 60599, IEEE c57.104‑2019, CIGRE TB 771 & TB 783, and recent industry experiences.
Beyond fixed limits: Baseline driven, trend focused Online DGA alarm strategy – Part I
This is the first part of an article which examines why many ODGA systems generate excessive or unreliable alarms when traditional fixed thresholds are applied to high-resolution data.
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