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Two-degree switched reluctance motor (SRM) can be selected to drive this motion system, such as boring mill, drill press and carving machine. To realize a precise position tracking for concentrated photovoltaic (CPV) power generation system, the paper presents an optimized rotary-linear motor based on switched reluctance principle. The structure of the motor for the power generation system is also...
The growth in the use of implanted medical devices, mobile devices and electric vehicles is exciting interest in wireless power transfer system. Wireless power transfer system (WPT) via magnetic resonant coupling was firstly proposed in 2007, and the system can transfer power to the receiving device over a distance of several times of the radius of the coils [1]. The WPT is not sensitive to the biological...
In the Joule Balance at the National Institute of Metrology (NIM), the dynamic measurement during the coil movement is avoided. But for this method a rather large current in the primary coil is needed to generate the necessary magnetic field in the force weighing phase. Thus the coil heating becomes an obvious uncertainty contribution. To solve this problem, a new coil system, in which the ferromagnetic...
A watt balance is a promising instrument to realize the unit of mass at the kilogram level. The magnet system is one of the key elements of such an instrument. For the new watt balance currently under construction at the National Institute of Standards and Technology, a permanent magnet system was chosen. We describe the construction of the magnet system, first measurements of the field profile, and...
The Joule balance method to measure the Planck constant and redefine the Kilogram ultimately has been going on at the National Institute of Metrology of China (NIM) since 2007. The first prototype has been built to check the feasibility of the principle. In 2012, the relative uncertainty of the plank constant measurement result is at 10−5 level. Self-heating of the coils, swing of the coil, etc.,...
The Joule Balance is one of the several promising methods for the precise measurement of the Planck constant h to redefine the kilogram. Compared with the Watt Balance, it benefits from its all static measurements. For the new generation of the Joule balance, a magnet system with high-permeability material is designed to reduce the problem of coil heating. Simulations are carried out to demonstrate...
The Hefei Light Source upgrade project (HLS-II) contains 8 dipoles, 32 quadrupoles (2 spares), and 32 sextupoles (2 spares) for the storage ring. Magnets were manufactured and magnetic measurements were performed in collaboration with the Institute of High Energy Physics (IHEP), China. Magnet production and validation measurements were finished in December of 2012. Measurements for all quadrupole...
The Joule Balance method, for the same purpose but different from the Watt Balance method, is going on at NIM for several years. The first measurement result of the Planck constant h is 6.6261(5)×10−34Js with a measurement uncertainty of 7.7 × 10−5. The further plan for improvement is discussed.
The precise measurement of Planck Constant h to establish a kind of quantum mass standard is an important but very difficult work. The Joule Balance method, for the same purpose but different from Watt Balance method, is going on in NIM for three years. The principle and progress are described.
VCA direct-drive XY table with a novel elastic decoupling mechanism is put forward. Which realizes the X and Y axial motion decoupling, diminishing its moving inertia, improving its dynamic performance. By establishing dynamical model of VCA and positioning table, X and Y axial positioning system dynamical characteristics is detailed respectively. The prototype experiment shows that the new XY table...
Traditionally, the most precise way to get the mutual inductance value is by a calculable mutual inductor. Here a new approach of measuring the mutual inductance at low frequency with compensation method is described. The mutual inductance is traced to the value of the frequency and resistance directly. The measurement uncertainty is 0.1 ppm and could be improved further.
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