Abstract: Electromechanical coupling dynamical system is representative multi-input, multi-output, non-linear, tight coupling, and uncertain system. Dynamical modeling and calculation of electromechanical coupling system play an important role in the deep exploration of dynamical-performance and improvement of control accuracy for complete electromechanical equipment. Thus, Lagrange-Maxwell equations have been deduced based on 2-DOF electromechanical coupling system and spindle unit of grain refitted machine tool for solid propellant rocket motor by using Park transform in dq0 coordinate system of servomotor. In this dynamical modeling method of electromechanical coupling system, to establish dynamical differential equations, it is needed to measure amplitude of the flux induced by the permanent magnets and the winding inductance in dq0 reference of the motor but not to measure the size of magnetic circuit. The equations deduction is terse, efficient, and the equations are easy to use. System differential equations have been established that include mechanism, servomotor and controller, which could be solved efficiently by Hamming method with high numerical accuracy and stability. The results of computer simulation prove the preciseness of formulation deduced and efficiency of differential equations solved.

Key words: Dynamics, Electromechanical coupling system, Solid propellant rocket motor