Development of mechanical PCS for SMES

(1)在瞬时PCS电流超过静态熄灭电流（熄灭延迟）之后，以时间延迟产生由灯电流激励的机械PCS的熄灭。(2)失超延迟归因于超导连接桥的温度由于磁通流动损失而变得高于临界温度的时间。(3)为了观测过冷液氮中气泡的行为，研制了一套光学观测系统。很明显，气泡在1毫秒内破裂，这比池沸腾液氮中的时间短得多。(4)研究了液氦中存在自由导电粒子时气泡的形成过程。实验结果表明，在粒子与电极碰撞的瞬间总是产生单个气泡，气泡的行为强烈地依赖于液氦的状态。

(1) Quench of the mechanical PCS, which was energized by the lamp current, generated with a time delay after the instantaneous PCS current exceeded a static quenching current (the quench delay).(2) The quench delay was attributed to the time in which the temperature of the superconducting connection bridge became higher than the critical temperature due to the magnetic flux flow loss.(3) An optical observation system was developed in order to observe bubble behavior in the subcooled liquid nitrogen. It became clear the bubble collapsed within 1ms, which was much shorter than in pool boiling liquid nitrogen.(4) Bubble formation process in the presence of free conducting particle in liquid helium was investigated. Experimental results showed that a single bubble was always generated at the moment of particle collision with the electrode and bubble behavior depended strongly on the state of liquid helium.