The most important feature of the servo press is
flexible slide motion because the servo machine can track the
trajectory smoothly and accurately. A conventional method is
field-oriented control (FOC) based on the mini-closed loop of
the electrical machine position. However, the moment of inertia
varies across slide positions, and the servo press is a strongly
nonlinear system. So linear control method utilizing kinematics
can not follow the curve very well. Meanwhile, this conventional
method also can not reduce the harm of backlash that must
exist in the mechanism of the servo press. So in this study,
the proposed method is adapted to the closed loop of crank
position. This method allows Lagrangian Approach to set up a
dynamical model. The torque reference of the computed torque
algorithm is implemented by model predictive current control. A
simulation and experimental study is coded on a dual-core DSP
and tested in a 1600 kN servo press prototype. These results
shows that the proposed method is effective and analyzed to be
better than the accuracy of the position and speed control of the
conventional method in detail. The contribution of this paper is
that the proposed method could improve the accuracy of crank
position and speed in the servo press.

computed torque, predictive current control, servo press