The Study Of A 45T Long Pulse Flat-Top High Magnetic Field Based On Battery Bank Power Supply

A battery bank power supply has been developed in the Wuhan National Pulsed High Magnetic Field Center(WHMFC) at the Huazhong University of Science and Technology(HUST). It can be configured into the different level of voltage and current or several power supplies to feed the different magnet loads by changing the battery numbers of in serial and parallel, or the structure of output BUS. In this paper, a 45 T long pulse flat-top magnetic field based on the battery bank power supp ly will be developed in order to meet the requirements of scientific research on the NMR and specific heat measurement for magnetic field with both longer pulse and steady flat-top. Under the analysis of the magnet structure parameter and simulation of power supply, the power supply and control system with three independent battery banks are designed. The main research is followed,Firstly, the three battery bank power supplies technology scheme is introduced to meet the long pulse flat-top high magnetic field for science experiment by using the battery goodness of high energy, DC output and no voltage ripple. It has very important value for science and industrial application.Secondly, the main parameters of the battery bank power supplies, as voltage, current, pulse width and so on, are determined by designing and analyzing of three coils magnet and battery bank. This system will be able to realize the 45T/100 ms flat-top long pulse high magnetic field.Furthermore, the MATLAB simulink modeling and simulation of the magnet and power supply is completed, and the main thyristor switch with forced commutation technology, the protective DC circuit breaker and structure configuration of three power supplies are also confirmed after the key parameters, as waveforms of voltage & current, flat-top, temperature rise in magnet, are optimized. The simulation results shows that the design is feasible.Based on the analyses above, the control system will be upgraded from the battery bank in WHMFC for the system safe operation with three power supplies and complicated electromagnetic environment. The control system, including timing control, real time data acquisition, fault signal diagnosis and protection strategy, can ensure the safety of magnet, battery, switch and operator when some serious short circuit or out of control faults happen.In the conclusion, the test and experiment plan will be shown, some suggestion and the future goal will also be discussed.