• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.196-199
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• 2003

Characteristics of a heater-triggered switch has been analyzed through the simulations and experiments. It was for the charging of Bi-2223 double pancake load with 1.7 mH and two heaters were used. The timing of the sequential control and the heating current with two heaters are important factors to generate pumping-current. The thermal analysis of the switch considering the heater input and time was carried out. Based on the analysis just mentioned. heater-triggered switch was fabricated. Characteristic analysis was carried out through two modes having different sequential timing controls. Maximum pumping-current reached 18 A and the pumping rate was 113 mA/s at that time.

• Progress in Superconductivity and Cryogenics
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• v.10 no.4
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• pp.13-17
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• 2008

This paper presents experimental and characteristic analysis of hgh-$T_c$ eater-triggered witch using coated conductor (CC) in liquid and gas helium. The high temperature superconducting insert coil which can be installed in a low temperature superconducting (LTS) magnet has been proposed and researched to generate higher magnetic field for MR. Since CC could be an attractive option for HTS insert, it is important to research he characteristics of heater-triggered switch employing CC. We performed the heater test and constructed simulation model using finite element method (FEM.) We performed a protection test and observed normal zone propagation (NZP) signals to evaluate the witch with protection of magnet.

• Progress in Superconductivity and Cryogenics
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• v.11 no.1
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• pp.30-34
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• 2009

This paper deals with charging and persistent-current mode operating characteristics of BSCCO magnet load using high-temperature superconducting (HTS) power supply. The HTS power supply consists of two heater-triggered switches, an iron-core transformer with the primary copper winding and the secondary BSCCO solenoid, and a BSCCO magnet load. The magnet load was fabricated by double pancake winding and its inductance is about 21 mH. A hall sensor was installed at the middle of the magnet load to measure the current in the load. In order to investigate the efficient pumping characteristics, operating tests of heater-triggered switch with respect to dc heater current were carried out, and the electromagnet current was determined by considering saturation characteristics of its iron core. The saturation characteristics of charged current in the magnet load were observed with respect to various pumping periods: 12 s, 14 s, 24 s and 32 s. After charging the magnet load, the persistent current was measured. The operating characteristics of the persistent current mode were mainly determined by joint resistance and magnet load.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.2039-2040
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• 2006

Persistent current switch (PCS) system in NMR, MRI, MAGLEV and SMES has many advantages, such as uniformity and durability of magnetic field and reducing a thermal loss, which enable many superconducting application to operate effectively. This paper deals with fabrication and test of heater trigger persistent current switch using coated conductor (CC) which has high n-index, critical current independency from external magnetic field and adaptable selectivity of stabilizer. PCS system consists of magnet power supply for energizing current to a magnet, heater, switch and magnet using coated conductor tape. Finite element method (FEM) is used to simulate thermal quench (switching) characteristic and design heater trigger. With FEM simulation, optimal length of heater is calculated by temperature and time analysis. Fabrication of PCS system and test of heater trigger characteristic were performed and compared with simulation result. This paper would be the foundation of researches of superconducting switching application.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.318-321
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• 2002

Superconductivity has various applications in the whole industry such as the generation of high magnetic field for medical care and diagnosis, the lossless power transmission, environment-friendly vehicles and clean energy storage systems. This paper deals with the High-Tc superconducting(HTS) power supply using heater-triggered switch for the charging of the superconducting magnets. HTS superconducting power supply consists of two heaters, an electromagnet, and Bi-2223 solenoid and Bi-2223 pancake is used as a superconducting load, similar to real HTS magnet. The timing sequential control of two heaters and an electromagnet is an important factor to generate pumping- current in the Bi-2223 load. The thermal analysis of switching parts of the Bi-2223 solenoid according to the heater input was carried out. Based upon the analysis, the 0.8A of heater current were optimally derived. The maximum pumping current reached 1.7A.

• Progress in Superconductivity and Cryogenics
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• v.17 no.3
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• pp.18-22
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• 2015

This paper deals with high-Tc superconducting (HTS) power charging system with GdBCO magnet, photo-voltaic (PV) controller, and solar panels to charge solar energy. When combining the HTS magnet and the solar energy charging system, additional power source is not required therefore it is possible to obtain high power efficiency. Since there is no resistance in superconducting magnet carrying DC transport current the energy losses caused by joule heating can be reduced. In this paper, the charging characteristics of HTS power charging system was simulated by using PSIM. The charging current of HTS superconducting power charging system is measured and compared with the simulation results. Using the simulation of HTS power charging system, it can be applied to the solar energy applications.