Technical Manual for EA350 Analog Pulse Type Servo Driver V101 6.10 Manual gain adjustment (basic) The EA350 series servo has an automatic gain adjustment function; yet due to restriction by load condition, automatic gain adjustment may be unable to meet requirements; to achieve the highest responsiveness and stability through coordination between the servo system and the machine, it is recommended to use manual gain adjustment. 6.10.1 Adjustment of the position control mode For the position control mode of EA350 series, refer to the block diagram of position control mode in Section 6.1. Adjustment of the position control mode shall follow the order below. 1) Activate the driver.
2) Set P4-00 to 0 3) For all gain parameters, default values are used 4) Enter the P4-10 load inertia ratio. It can be identified by the driver through the AF-05 function (with restrictions), or manually calculated 5) Values in the table below are used as reference for adjustment. 6.10.2 Adjustment of the speed control mode For the speed control mode of EA350 series, refer to the block diagram of speed control mode in Section 6.2. Adjustment of the speed control mode is similar to adjustment of the position control mode. The only difference is that no adjustment of the position loop gain P4-02 and the speed feedforward gain P4-06 is required.
6.10.3 Adjustment of the torque control mode For the torque control mode of EA350 series, refer to the block diagram of torque control mode in Section 6.3. The essence of torque control is to control the torque based on speed control. For this reason, it is mainly required to set the torque limit and the speed limit. ➢ Upon torque control, the reverse direction refers to the rotating direction of the motor and the opposite direction of the torque command. This circumstance may occur when traction is applied in the reverse direction by an external device. In this circumstance, the motor is in the continuous power generation state and the drive will give an alarm.
It is required to provide a proper external braking resistor, and correctly set the P8-10, P8-11 and P8-13 according to parameters of the braking resistor. ➢ The speed limit is only valid in the torque command direction; when the motor is reversely dragged by an external device, the driver only controls the output torque of the control motor, while the motor speed is determined by the external device. ➢ When the motor speed reaches the limit in the torque command direction, the driver will switch from the torque command-based torque control to speed control with speed limit as the command.
➢ To ensure stable operation at the speed limit, it is required to set the speed loop parameter according to adjustment of the speed control mode. ➢ When the speed limit is too low, the speed loop gain is too low or the speed loop integral time constant is 3000.0 (integral invalid), if the input of torque limit reduces, torque output following a command may fail sometimes. ➢ Upon torque control, the following functions are invalid:
Acceleration feedback Disturbance observer Speed observer Torque feedforward Online inertia identification Gain switching Adaptive filter Friction compensation Notch filter 6.10.4 Gain switching Upon gain switching according to internal data or external data, the following results can be realized: Reducing the gain upon stop (servo locking) to suppress vibration. 71 Order Parameter Parameter name Reference value Adjustment method 1 P4-03 Speed loop gain 18.0 Increase within a range where no abnormal noise or vibration occurs. Decrease when abnormal noise is produced. 2 P4-31 Torque command filter 1.26 To suppress vibration after stop, increase P4-03 and reduce P4-31.
If excessive vibration occurs at the instant of stop, try to reduce P4-31 3 P4-02 Position loop gain 32.0 Observe the positioning time; increase the set value, and positioning is expedited. A significant change may cause vibration. 4 P4-05 Speed loop integral time constant 31.0 No adjustment is needed if the operation is normal When the value is reduced, the positioning time is shortened; if it is shortened too much, vibration will occur. If the value is too high, the position deviation may diverge.
Increase within a range where no abnormal action or noise occurs 5 P4-06 Speed feedforward gain 30.0 When the feedforward amount is set too high, occurrence of overshooting and jitter of the positioning completion signal may make reduction of the setting time impossible. When the command pulse input is non-uniform, improvement can be made by increase the set value of P4-07.