Abstract: Aiming at the problem of changing moment of inertia to the motor shaft during a crank servo presss trip, the control parameters tuning method of proportionalintegral (PI) controller for current loop and speed loop of servo press was studied. The kinematics analysis of the slidercrank mechanism was derived and the functional relationship between the crank angle and equivalent moment of inertia of the slider was defined. A piecewise control method for PI parameters based on the GTSD14 series intelligent drivers of Googol Technology Co., Ltd. was proposed. In a single stroke, the PI parameters of the controller were determined according to the corresponding moment of inertia of the crank in different positions to improve the following performance of the speed and position loops of the system. An experiment platform was established and experiments taking a servo motor with different additional weights as a simulation object were carried out. The experimental results indicate that when the actual inertia of the system does not match the PI parameters of the controller, the system can adjust the PI parameters online, which improves the following ability of the motor speed loop and position loop, thus verifying the feasibility of adjusting the PI parameters in real time with the change of the moment of inertia of each segment.
Key words: variable moment of inertia;define control object model by geometric relationship; integrated drive and control; PI parameters online adjusting