基于DVM的测量系统中的不确定性来源,用于量子化大厅电阻标准
Kevin C Lee1, Marvin E Cage1, Patrick S Rowe1
1National Institute of Standards and Technology, Gaithersburg, MD 20899-0001.
概括
一个新的自动化系统使用量化霍尔电阻校准10kΩ标准电阻. 该系统为标准化实验室中精确的电阻校准提供了一个简单,具有成本效益的解决方案.
科学领域:
- 电气计量学 电气计量学
- 阻力标准 阻力标准
- 量子现象是一种量子现象.
背景情况:
- 便携式10kΩ电阻被广泛使用,但随着时间的推移而漂移.
- 对量子化霍尔电阻等不变标准进行重新校准是必要的.
- 一个简单,廉价的校准系统对初级标准实验室有好处.
研究的目的:
- 开发一种简单的,自动化的测量系统,用于校准10kΩ标准电阻.
- 为了比较10kΩ电阻器与量子化霍尔电阻的性能.
- 分析不确定性来源并实现高精度校准.
主要方法:
- 使用一个单一的,高精度的商用数字电压计 (DVM).
- 采用了一个系统来比较在相同电流下的10kΩ电阻和量子化的霍尔电阻之间的电压.
- 为了提高效率和精度,自动化了测量过程.
主要成果:
- 成功确定了10kΩ标准电阻的值.
- 识别和分析测量系统中的所有不确定性来源.
- 实现了相对组合标准不确定性低于1×10-7 (0.1 ppm).
结论:
- 开发的自动化系统提供了一种简单有效的方法来校准10kΩ电阻.
- 该系统表现出高精度,适合主要标准实验室.
- 这有助于更频繁,更具成本效益地重新校准基本电阻标准.
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