能量天平反馈系统的改进  

Improvements in the feedback system of Joule balance

作　　者：李辰[1] 贺青[2] 张钟华[2] 李正坤[2] 韩冰[2] 

机构地区：[1]清华大学精密仪器系,北京100084 [2]中国计量科学研究院,北京100013

出　　处：《仪器仪表学报》2014年第5期987-993,共7页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(50677065);国家科技支撑计划(2011BAI02B03)资助项目

摘　　要：未来质量单位的定义有可能在很大程度上依赖于普朗克常数h的测定值和不确定度。能量天平方案作为我国提出的解决量子质量基准的电学方法,相比于功率天平方案,在测量普朗克常数h方面有自己独特的优点。着重对能量天平方案中的天平反馈系统进行了研究。通过反馈系统实现了天平的快速平衡,并通过对天平反馈执行器的电路调整,显著改进了天平系统的测量漂移现象和噪声。零位漂移从13 mg降低到7 mg,测量噪声降低到5 mg以下。In the future,the definition of the mass unit may depend heavily on the measured value and uncertainty of the Planck constant h.The Joule balance scheme as one of the electrical methods currently used in quantum mass standard solutions is first proposed by NIM.Compared with the Watt balance scheme,the Joule balance scheme has its own advantages in the measurement of Planck constant h.This paper focuses on the feedback system and actuators of the Joule balance.Through the circuit adjustments of the feedback system and actuators,the drift phenomenon and the noise during the measurement of the Joule balance have got significant improvement.The zero drift is reduced from 13mg to 7mg,and the measurement noise is reduced to 5mg or less.

关 键 词：千克 量子质量基准 能量天平 反馈系统 漂移 

分 类 号：TB971[一般工业技术—计量学]