Research On Design Technique Of An 80t Pulsed High Field Magnet

A systematic study of the design and performance of pulsed magnets energized by capacitor banks has been researched on. The theoretical aspects of this study are the electrical discharging calculation, stress calculation and cooling down analysis. The peak stress determines the magnetic field that can be obtained, while the Joule heating determines the pulse duration.In discharging calculation, magneto-resistance and eddy current are taken in to account precisely, which affects the pulse shape and the temperature distribution. Both effects decrease the peak field by increasing the resistance, and in addition eddy current decreases the rise time by decreasing the inductance, which results in a peculiar spike in dB/dt at the beginning. However, the influence on the pulse shape and the peak field is not so strong; both effects enhance the Joule heating and therefore result in a radial temperature gradient with the highest temperature at the inner surface of the coil. The temperature differences up to 100~K develop during the discharge. In stress calculation, thermal stress, pre-stress and Maxwell stress are taken into account. Significantly higher stresses result due to temperature gradients and non-uniform current distribution, which can be partly offset by pre-stressing reinforcement fibers.Compressive stress on the axial direction leads more high stress. So, during the construction of a magnet, a low compressive stress is better. This dissertation also analysis the affects of the discharge process and the stress state by using the stainless steel as the reinforcement.At last, some discussions on the rapid cooling have been made. Much more rapidly cool-downs can be made by using axial channels in the magnet.