EA180 Series Servo Drive Users Manual * The reference compensation value of each friction torque is the rated torque of the motor. Positive direction Speed command P4-31 Viscous friction compensation gain P4-33 Forward torque compensation value Time Motor OFF Assuming that the torque command is T, the compensated torque command Tb is: Forward rotation direction: Tb=T+P4_32+P4_31* motor speed /1000+P4_33 Reverse rotation direction: Tb=T+P4_32+P4_31* motor speed /1000-P4_34 Friction torque compensation is invalid in torque control mode.
6.11.1 PDFF control When the speed command drives the motor to rotate, the action characteristics of the motor shaft itself also depend on the response characteristics of the mechanical system because the shaft end of the servo motor has a mechanical load. Considering the needs of various mechanical systems, EA180 servo drive designs PDFF controller in speed loop and uses it in non-torque mode. PDFF controller is a kind of controller between PI and IP controllers, which has the characteristics of both PI and IP controllers. IP controller structure:
- TCMD VCMD + Integrator Ki + - Kp PC 70 P4-33 Forward torque compensation It is added to torque command when the motor is running in the forward direction to compensate for the forward dynamic friction. * The physical direction of forward and reverse rotation of the motor is determined by P0-01. P4-34 Reverse torque compensation It is added to torque command when the motor is running in the reverse direction to compensate for the reverse dynamic friction. P4-31 Viscous friction Negative direction compensation gain Motor ON Attention☞