Abstract: The control driving module the essential component of nuclear reactor rod control system, which is used to generate the exciting current of control rod drive mechanism. There is a large amount of stray inductors and capacitors in driving circuit caused by complex cable arrangement, which results in high-frequency oscillations during circuit changes. On the one hand, the actual operation current may exceed the limit value of the components. On the other hand, the high-frequency oscillating currents can generate serious electromagnetic interference, affecting the normal operation of adjacent sensitive devices or circuits. In this work, the transient process of circuit switching is analyzed by frequency-domain analysis method based on the parasitic parameter network model, and the main excitation sources and oscillation networks that affect the oscillation current are clarified. Then, the influence degree of each key parameter of the system on the oscillation peak is further analyzed through Matlab/Simscape simulation. Finally, an optimization method for overstress at oscillation peaks is proposed in combination with the electrical performance of the components. The research results provide a theoretical basis for improving the environmental tolerance of the control drive module and reducing the risk of device failure.