We have published a new 50-page technical white paper: Laser Photoacoustic Spectroscopy (L-PAS) for Online DGA of Transformer Oil — a technically neutral, evidence-based reference for asset managers, protection engineers, and procurement decision-makers who evaluate online dissolved gas analysis (DGA) for power transformers.
Why this white paper
Online DGA is the most widely applied condition-diagnosis method for oil-filled transformers, yet vendor claims about measurement technology vary widely. This white paper gives you an engineering-level grounding: how laser photoacoustic spectroscopy actually works, what performance it delivers in the field, and how it compares with gas chromatography (GC), broadband infrared photoacoustics, NDIR, and FTIR — including cost of ownership over a 10-year lifecycle.
What is inside
- Technology fundamentals — the photoacoustic effect, narrow-linewidth laser excitation (~15 fm), zero-background indirect measurement, and why L-PAS achieves virtually no cross-interference from other gas species or moisture.
- Full fault-gas coverage — 9 gases plus moisture (H₂, CO, CO₂, CH₄, C₂H₂, C₂H₄, C₂H₆, N₂, O₂, H₂O), covering every fault type in IEC 60599:2022 (PD, D1, D2, T1, T2, T3).
- Detection limits — commercial online L-PAS reaches a C₂H₂ lower detection limit of ≤0.1 ppm, meeting early-warning requirements for discharge-type faults.
- Sampling & system architecture — headspace, vacuum, membrane, and vacuum-assisted membrane degassing; oil-circuit safety; T63 response; MODBUS RTU/TCP, IEC 61850, IEC 60870-5-104, and DNP3.0 integration for digital substations.
- Diagnostics & intelligence — IEC gas ratios, Rogers, Duval triangle/pentagon (IEEE C57.104-2019), trend and gas-generation-rate analysis.
- Selection & economics — a seven-dimension RFQ framework and an ROI evaluation model for pilot, evaluation, and scale-up stages.
Companion resources
For a shorter introduction, see our explainer on laser photoacoustic spectroscopy as the 4th generation of DGA monitoring, the PAS technology guide, and the DGA technology comparison. The DGA-900 product page shows a full 9-gas + moisture LPAS implementation, and our DGA fundamentals section covers the diagnostic methods behind interpretation.
The white paper is free. Complete a short form and the full 50-page PDF is delivered instantly.