In order to study the dynamic characteristics of the submersible pump system and the influence of the structural parameters of the speed-limiting torque control valve (STC valve) on the dynamic performance of the spool,based on the analysis of its working principle and mathematical model,a multi-domain unified modeling language Modelica was used to build STC valve subsystem models and remote control valve group subsystem in MWorks simulation software,and the established subsystem model was combined with the constant pressure variable pump and centrifugal pump models to construct a complete submersible pump system model.This model was used for system simulation to analyze the impact of STC valve orifice diameter and spool quality on the dynamic performance of the spool.The research results show that the submersible pump system has good dynamic characteristics;the smaller the diameter of the orifice of the STC valve is,the more stable the movement speed of the spool is,the smaller the speed oscillation is,and the faster the steady state can be achieved;the more the quality of the STC valve spool larger is,the smaller the speed vibration of the spool is,the smoother the movement is.