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等离子体系统中存在两个或多个电流片时，电流片中发生的不稳定性可能会相互作用．行星际磁场北向时，背阳面碰层顶电流片与磁尾等离子体片之间可能发生相互作用，高纬边界层强烈的流场剪切可能促进磁场重联，产生磁层亚暴．本文运用二维可压缩磁流体模拟研究具有强流场剪切的多个电流片系统中磁场重联的演化．结果表明，Kelvin－Helmholtz不稳定性使多电流片系统的磁场重联过程明显加快；相邻电流片之间的距离越近，两者相互作用越强，重联增长率越大；在三电流片系统中，超Alfven速度强流场导致外侧两个电流片中出现强烈的磁场重联，并引发中心电流片的磁场重联．行星际磁场北向时，也可能发生磁层亚暴．
When two or more current pieces are present in the plasma system, the instabilities that occur in the current pieces may interact. In the northward direction of the interplanetary magnetic field, the interaction between the top current sheet and the tail magnetic sheet may occur. The strong shear field in the high latitude boundary layer may promote the reconnection of the magnetic field and produce the sub-stratospheric magnetosphere. In this paper, two-dimensional compressible magnetic fluid simulations are used to study the evolution of magnetic field reconnection in multiple current-slice systems with strong field shear. The results show that Kelvin-Helmholtz instability accelerates the magnetic field reconnection in multi-current system. The closer the distance between adjacent current plates, the stronger the interaction between the two, the greater the rate of reconnection. In the three current In the system of slices, a strong flow field with ultra-Alfven velocity leads to a strong magnetic reconnection in the two outer current slices and a magnetic reconnection in the center current slice. Magnetospheric sub-storms may also occur when the interplanetary magnetic field is northbound.