EA180 Series Servo Drive Users Manual Example of speed feedforward use When the factory value (5ms) is used for the speed feedforward smoothing filter, the speed feedforward gain is gradually increased to make the speed feedforward valid. At a certain speed, the position deviation during the action can be adjusted according to the following formula: command position to ing correspond Speed = unit) (command deviation Position ） （ gain d feedforwar Speed 100 gain loop Position If the speed feedforward gain is adjusted to 100%, the position deviation is 0 in calculation, but this will produce huge overshoot during acceleration and deceleration.
In addition, when the pulse frequency of position command input is low or uneven, the speed feedforward gain may bring about large impact and sound during operation. Please use a position command filter (inertial filter P1-14, position FIR filter P5-23). Example of torque feedforward use When torque feedforward is used, the load inertia ratio P4-10 needs to be correctly set. Please use offline inertia identification to obtain it, or calculate it according to the actual mechanical situation. When the torque feedforward smoothing filter time constant is at the factory value (5ms), the torque feedforward gain is gradually increased to make the torque feedforward valid.
By providing torque feedforward gain, the position deviation can be close to 0 during fixed acceleration and deceleration, so under the ideal condition of no external interference torque, the position deviation of all actions areas during trapezoidal speed curve driving can be approximately close to 0. Actually the external interference torque must exist, so the position deviation cannot be 0. 100 6.11.2 Friction torque compensation There must be friction in machinery. According to different machinery, there are mainly three forms of friction. EA180 provides compensation for the three types of friction.
Associated parameters 69 P4-07 Speed feedforward filter time constant Set the time constant of the primary inertial filter required for the speed feedforward input to reduce harmonic components in the command. P4-24 Torque feedforward gain Position control mode: The torque command obtained by second-order differentiation of the external position command is multiplied by the ratio set by this parameter, and the result is added to the torque command after speed control processing. Speed control mode: The torque command calculated from the internal speed command is multiplied by the ratio of this parameter, and the result is added to the torque command after the speed control processing.
P4-25 Torque feedforward filter time constant Set the time constant of the primary inertial filter required for the speed feedforward input to reduce harmonic components in the command. Function Parameter name Function code P4-30 Friction compensation smoothing time constant Carry out one-time inertial filtering for the three torque compensation values to avoid vibration and other problems caused by a sudden change of torque command, but a large set value will cause a slow compensation effect. P4-31 Viscous friction compensation gain The product of the command speed and this set value is added to the torque command as a torque compensation value.
* Used to compensate for the case where the friction force increases linearly with the increase of speed. P4-32 Torque command added value It is added to the torque command in a fixed direction. A positive value indicates that the added value direction is the forward direction of the motor rotation, while a negative value indicates that the added value direction is the reverse direction of the motor rotation. * As long as the servo drive is ON, torque will be added even if there is no command.