The National Institute of Metrology(NIM)has been studying the Joule Balance method(which is used for the same purpose as the Watt Balance method but operated differently),for several years to establish a kind of quantum mass standard by means of measuring the Planck constant. Since 2010,some progress has been achieved. A new standard square wave compensation method has been developed to measure the DC mutual inductance with an uncertainty of several parts in 10 - 7(k = 1). . An eddy current sensor for positioning has been designed and implemented to obtain a more accurate position of the movable coil. . The alignment technique for the coil system has also been placed under consideration. Specifically,a newly developed oil damping device reduces the small swing of the coil set(which occurs because of a combination of the weak vibration of the balance base and the hot ascending warm air from the current heating of coils). As a result,the measurement uncertainty of the coil position and mutual inductance is improved. . The recent measurement result of the Planck constant h is 6. 626104(59)× 10 - 34 J·s with an uncertainty of 8. 9 × 10 - 6( k = 1). Further improvements and difficulties are also discussed.%能量天平法已在中国计量科学研究院开展了几年的研究。研究的目的与功率天平法是一致的，即通过测量普朗克常数来建立质量量子基准，但具体方法不同。2010年以来该项研究取得一定进展。例如对于直流互感量测量这一关键问题，已研究出一种新的方波补偿方法，测量不确定度达到10-7量级（k =1）。还研发了一种涡流传感器，可更准确地对可动线圈定位。线圈系统的准直问题也得到进展，研制了一种油阻尼器，大大减小了由于天平基础振动和线圈加热上升气流引起的线圈抖动。这些措施改善了线圈位置及互感测量的不确定度。测量普朗克常数h 的最新结果为6.626104（59）×10-34 J·s，综合的相对不确定度为8.9×10-6（k =1）。对所遇到的困难和进一步的改进措施也在文中进行了讨论。
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