中文摘要：

将质量单位千克溯源到普朗克常数上是目前计量领域公认的实现质量重新定义的方法。能量天平法则是我国提出的用来测量普朗克常数与复现质量的一种方案。与国外采用的功率天平法相比,能量天平法拥有静态测量的优点。第一代能量天平系统已经完成了整体系统实验,对其不确定度的详细分析,有助于进一步优化设计方案,改进实验过程。最后得到其整体的不确定度为2.5×10^-6。针对其中主要的不确定度来源,在第2代能量系统中分别提出了相应的改进办法,为进一步降低实验不确定度提供了保证。

英文摘要：

The redefinition of the unit of mass by tracing kilogram to Planck constant has been widely accepted in the field of metrology. In China, Joule balance method is proposed by NIM to measure the Planck constant and redefine the kilogram. Compared with the Watt balance method in other countries, Joule balance method benefits from the advantage of static measurement. The whole system experiments for the first generation of the Joule balance system have been finished. The whole measurement uncertainty was analyzed in detail, which will help us to further optimize the design scheme and improve the experiment process. Finally, we obtained that the whole measurement uncertainty is 2.5 × 10^-6. Aiming at the major sources of the measurement uncertainty, several improvement methods are put forward for the next generation of the Joule balance system, which provides the ensuring measure for further reducing the measurement uncertainty.