Abstract: It is put forward higher requests to the NC machine tool for high speed and high acceleration, which increases the difficulty of the research on the electromechanical coupling. The analysis are carried out from the theory analysis and simulation respectively which involve the frequency characteristics and their variation of the NC system, the servo system, the mechanical system and the cutting force under high speed and high acceleration. Its effects are explored on the electromechanical coupling in the feed system. The results show that with the increase of velocity and acceleration. The distribution of the quality of the mechanical system vary with the position; the axial stiffness of screw nut vice and bearing vice vary with the acceleration, meanwhile, the stiffness exist discontinuity. Because of the nonlinear effects of the inductance, with the increase of velocity, the frequency and amplitude of servo output force increase; with the increase of acceleration, the amplitude of force increases. The influence of cutting tool installation offset on the cutting force become more obvious and the frequency components of cutting force increase. The interaction of each system becomes more complex, and the influence of electromechanical coupling on the dynamic precision become more prominent.

Key words: Dynamic precision, Electromechanical coupling, Frequency characteristics, High speed and high acceleration, Time-varying characteristics