Uncertainty analysis for ac-dc difference measurements with the AC Josephson Voltage Standard
1National Institute of Standards and Technology, 100 Bureau Drive, MS 8172, Gaithersburg, MD 20899-8172, USA.
Summary
This study analyzes uncertainties in AC Josephson Voltage Standard (ACJVS) measurements. ACJVS offers significant uncertainty reduction for audio frequencies compared to traditional thermal converter methods.
Area of Science:
- Electrical Metrology
- Quantum Voltage Standards
Background:
- Accurate AC-DC difference measurements are crucial for electrical metrology.
- Conventional methods using thermal converters have limitations in uncertainty and frequency range.
Purpose of the Study:
- To analyze uncertainties in AC-DC difference measurements using an AC Josephson Voltage Standard (ACJVS).
- To compare the uncertainty performance of ACJVS with conventional thermal converter methods.
Main Methods:
- Detailed uncertainty analysis of ACJVS measurements.
- Comparison of ACJVS with thermal transfer standards (TTS) and digital voltmeters.
- Monte Carlo sensitivity analysis for transmission line parameters.
Main Results:
- ACJVS reduces combined uncertainty by factors of 2 to 10 for audio frequencies (<200 mV).
- Type A uncertainties are limited by the thermal transfer standard or digital voltmeter.
- Transmission line impedance and on-chip inductance significantly impact accuracy above 10 kHz.
Conclusions:
- ACJVS provides a superior method for AC-DC difference measurements at audio frequencies.
- Understanding and mitigating uncertainties in transmission line parameters is key for high-frequency accuracy.
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