周期驱动下的磁力摆在一定条件下可以实现与驱动信号的相位锁定，从而产生稳定的等幅振动.本文测量了磁力摆相位锁定建立的暂态过程以及相位锁定点与控制参数的关系.基于单摆的非线性以及磁场驱动力与相位差的定性依赖关系， 所有实验结果都可以得到很好的解释.

In certain conditions，magnetic pendulum periodically driven by a coil can become phase-locked with the driving signal and lead to stable oscillation. We study the transient process of the phase locking and measure the amplitude and phase of the pendulum in various controlling conditions. Based on the nonlinearity of 　　pendulum and the phase-dependent energy transfer between the pendulum and driving coil，a negative feedback mechanism is identified in the system，from which all the experimental results can be explained quantitatively.