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Two groups of magnetopause shape control coils are used on the SPERF (Space Plasma Environment Research Facility) facility to regulate the magnetic field configuration of the simulated Earth's magnetopause magnetic reconnection. Here, design and construction of the magnetopause shape control coils is presented to resolve the issues regarding the strong pulsed current, high voltage, and vacuum sealing, etc. At first, the physical requirement imposed on the coils is explained, followed by clarification of the key technological issues facing the coils' design. Afterwards, the fundamental design of the coils is shown, with emphasis on the segmented structure and reliable vacuum sealing. Then, the supporting and motion mechanism of the coils are designed, and the layout of the leading wires in the supporting tubes is optimized to alleviate the impact of the magnetic forces between them. Further, the connection structure is designed to connect the leading wires of the coils with the pulsed power supply. At last, the critical measurements done for the magnetopause shape control coils are given to demonstrate the design. Presently, installation of the coils on the SPERF has completed, and they will be used in the physical experiments in the future. • Two magnets are designed and constructed for researching the 3D magnetic reconnection. • Structure design of the magnets is presented. • The issues regarding the eddy current, magnetic force, and vacuum sealing are addressed. • The strength of the magnets' supporting mechanism is assessed by the mechanical analyses. • The possible research based on the magnets is discussed. [ABSTRACT FROM AUTHOR]

Geomagnetic storm in the magnetosphere of the earth is significant in understanding the basic space plasma processes such as wave-particle interaction and predicting the space weather related to the human activity. Due to defects involved in the space observation and theoretical modeling, it is urgent to investigate it in the laboratory based on a simulation facility. To that end, two circular magnetic perturbation magnets are proposed in the SPERF (Space Plasma Environment Research Facility) to generate the magnetic disturbances with different characteristic times for studying the response of the inner magnetosphere to the geomagnetic storm. The paper focuses on the engineering design and construction of the magnets. The scaling relation for geomagnetic storm simulation is presented, serving as the design requirement of the magnets. Then, starting with giving the designed parameters of the magnets satisfying the requirement and analyzing the crucial issues facing their engineering design, the design results, manufacturing procedure, and test results are presented, with emphasize on the measures to improve the insulation, vacuum degree, and plasma quality. Then, mechanical analyses are done to evaluate the strength of the supporting mechanism of the magnets under the magnetic force and torque caused by the possible deviation from the concentricity with the dipole magnet. Afterwards, a connection scheme is designed to make the coaxial cables connecting to the magnet's leads go through the vacuum vessel considering the constraints of the magnetic-force impact, thermal burden, and motion requirement. One of the magnetic perturbation magnets has been installed in the SPERF, and is now being tested combined with the pulsed power supply. • Two magnets are designed and constructed to simulate the geomagnetic-storm magnetic disturbances. • The scaling relation for simulating the geomagnetic-storm magnetic disturbance in the laboratory is presented. • The issues regarding the vacuum, pulsed strong current, and plasma are addressed. • The strength of the magnet's supporting mechanism is demonstrated by the static and modal analyses. • The possible research based on the magnets is discussed. [ABSTRACT FROM AUTHOR]

The Space Plasma Environment Research Facility aims to research the space plasma physics in the laboratory. Two elliptical magnets are used to form a magnetic mirror field simulating the interplanetary magnetic field to investigate the magnetic reconnection at the magnetopause and magnetotail of the earth on the ground. To perform the research, the issues facing the magnets in terms of high pulsed current, vacuum, plasma, and mechanical support must be resolved. The paper presents their design and construction process to settle these issues. A series of measures are adopted to enhance insulation, reduce the gas leakage, and avoid tip discharge, ranging from the dielectric layers to the Inconel spraying. A transition structure considering the effect of the strong pulsed current is designed for connecting the magnet's leads to the cables of its pulsed power supply. In addition, a supporting and motion mechanism is proposed to hold the magnets and drive them to move. The strength of the mechanism is assessed by the static mechanical analysis for the extreme magnetic force load. Meanwhile, a connection scheme compatible with the supporting and motion mechanism is proposed to guide the cables through the vacuum vessel. The great mechanical stress occurring at the interface between the cables and the stainless-steel blocks due to the sheared magnetic force is reduced considerably by a fixing plate. The results in the paper are valuable for designing the magnet conducting a large pulsed current in the vacuum environment for plasma applications. [ABSTRACT FROM AUTHOR]