Upgrade of the Pulsed Magnetic Field System With Flat-Top at the WHMFC

Wang, Shuang; Peng, Tao; Jiang, Fan; Jiang, Shan; Chen, S.; Deng, Le; Huang, Rundong; Li, Liang

doi:10.1109/tasc.2020.2969108

Cited by 28 publications

(10 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The resolution of our method depends on the applied excitation voltage, the temperature increment ΔT, the resolution of the electronics, and the electric noise. Nonetheless, the typical resolution of the constructed calorimeter can reach 1 nJ/K at 1 K, which is better than that of commercially available calorimeters (~2 nJ/K at 2 K) [21] as well as that of previous pulsed-field calorimetry [6][7][8][9]. This resolution is achieved owing to the highly stabilized flat-top field, the small C ad , and the sensitive RuO 2 thermometer.…”

Section: Discussionmentioning

confidence: 99%

“…Finally, we note the time efficiency of the present measurement techniques. For earlier pulsed-field calorimetry [6][7][8][9], the data points of heat capacity are sometimes insufficient to discuss physical properties in detail, because only few data points were obtained in each field pulse. However, owing to small t 2 , our calorimeter can collect 10-50 data points for each field pulse by employing the quasi-adiabatic or the dualslope method.…”

Section: Discussionmentioning

confidence: 99%

“…In the last decade, the measurement frequency was improved to 1 ~ 2 kHz with the use of a thin-film thermometer [6] and to 1 ~ 10 kHz with applying AC technique [7]. However, the achieved data quality of heat capacity has been strongly limited due to the electromagnetic noise from a rapid field sweep [6][7][8][9], and further improvements of the measurement technique have been desired for detailed thermodynamic studies in high magnetic fields.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

High-resolution calorimetry in pulsed magnetic fields

Imajo

Dong

Matsuo

et al. 2021

Review of Scientific Instruments

View full text Add to dashboard Cite

We have developed a new calorimeter for measuring thermodynamic properties in pulsed magnetic fields. An instrumental design is described along with the construction details including the sensitivity of a RuO 2 thermometer. The operation of the calorimeter is demonstrated by measuring heat capacity of three samples, pure Germanium, CeCu 2 Ge 2 , and κ-(BEDT-TTF) 2 Cu[N(CN) 2 ]Br, in pulsed fields up to 43.5 T. We have found that realization of field-stability is a key for measuring high-resolution heat capacity under pulsed fields. We have also tested the performance of the calorimeter by employing two measurement techniques; the quasi-adiabatic and dual-slope methods. We demonstrate that the calorimeter developed in this study is capable of performing high-resolution calorimetry in pulsed magnetic fields, which opens new opportunities for high-field thermodynamic studies.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High-resolution calorimetry in pulsed magnetic fields

Imajo

Dong

Matsuo

et al. 2021

Review of Scientific Instruments

View full text Add to dashboard Cite

show abstract

“…When the last dual-capacitors stage is over, the last following bank will energize the magnet alone, and the system will end up discharging in this single-capacitor stage. The entire discharge process of the FTMF system can be calculated by ( 5), ( 12), ( 14), and (15). However, the closed-form solutions of these equations can not be obtained with a variable resistance of magnet based on (1)-( 4).…”

Section: B Dual-capacitors Stagementioning

confidence: 99%

“…The undesirable temperature rise reduces the pulse width of the FTMF and lengthens the time it takes for the magnet to cool down. A 64 T/10 ms FTMF with 0.3% ripple with coupling capacitors loops is also achieved at WHMFC [15]. A pulsed current with a 26 kA/12 ms flat-top is realized by the capacitor power supply at the Laboratory for Space Environment and Physical Sciences in China [16].…”

Section: Introductionmentioning

confidence: 99%

Generation of a Flat-Top Magnetic Field With Multiple-Capacitor Power Supply

Ding

Fang

et al. 2022

IEEE Access

View full text Add to dashboard Cite

The flat-top magnetic field (FTMF) can meet scientific experimental requirements for higher magnetic intensity, longer flat-top pulse width, and lower ripple in physics, chemistry, biology, and other scientific fields. This paper proposes an FTMF system powered by the multiple-capacitor power supply (MCPS). The MCPS consists of several capacitor banks with customizable capacitance and given voltage. These banks discharge sequentially based on the designed time-series to yield an FTMF. Compared with other methods for generating the FTMF, the MCPS can easily generate FTMFs with high parameters and flexible adjustability of the pulse width. Due to the coupled variable parameters between and within the power supply and the magnet, a hybrid algorithm based on the genetic algorithm (GA) and particle swarm optimization (PSO) is applied to calculate the discharge parameters of the MCPS. The optimal solution from the GA-PSO hybrid algorithm is visualized and selected by the basis vector method. For verifying the effectiveness of the MCPS and the optimization method, a series of FTMFs at different magnetic field strength levels are modeled in MATLAB/Simulink and achieved in the experiment. The generated FTMF with the highest field strength is 50 T, its pulse width is 70 ms, and ripple is less than 0.7%.INDEX TERMS Flat-top high magnetic field, multiple-capacitor power supply, multi-objective optimization, GA-PSO hybrid algorithm.

show abstract