NRC-PTB intercomparison of voltage transformer calibration systems for high voltage at 60 Hz, 50 Hz, and 16.66 Hz
Bibliographic record
Abstract
An intercomparison of voltage transformer (VT) calibration systems was performed at the PTB high-voltage laboratory. A "portable" current-comparator-based VT calibration system of the NRC was compared with the PTB voltage-divider-based system, using a reference multiratio inductive VT as a transfer standard with voltage ratios of (110/2 kV)/(100/2 V) up to (400//spl radic/3 kV)/(100//spl radic/3 V) at frequencies of 16.66 Hz, 50 Hz, and 60 Hz. At frequencies of 50 Hz and 60 Hz with a resistive burden of 10 k/spl Omega/ and test voltages of 20% up to 120% of rated voltage, the test results of the two different methods at all ratios were found to differ by no more than 15 parts in 10/sup 6/ for the voltage ratio and 30 /spl mu/rad for the phase displacement. For the ratio (110/2 kV)/(100/2 V) at 16.66 Hz, the results agreed within 15 parts in 10/sup 6/ for the voltage ratio and 50 /spl mu/rad for the phase displacement.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.007 | 0.012 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".