The speed loop response frequency must be 4~6 times higher than that of the position loop; otherwise vibration may be caused. Position loop response frequency fp APR _ P /2 π Speed loop response frequency fv = ASR _ P X P 4_10 Parameter functions: Set the speed loop differentiation time constant; when the set value is 0.0, there will be no differentiation action. Differentiation shall be carefully used. Use of differentiation may be considered when commands fluctuate but stable output is desired. Besides it shall be used in combination with P4-26 differentiation output limit to avoid severe differentiation resulting in system oscillation. Parameter functions:
Set the speed loop integral time constant; when the set value is 3000.0, there will be no integral action. The smaller the set value is, the closer to 0 the deviation is upon stop; however, if the value is set too small, vibration may be caused. Generally, a greater load inertia shall correspond to a larger setting of the speed loop integral time constant. If setting of the load inertia ratio P4-10 is consistent with the actual conditions, the following formula can be used to derive the speed loop integral time constant ASR_Ti : ASR _ Ti ≥5000/2 πfv Parameter functions: Set the speed feedforward gain.
The product of the speed command obtained through calculation of the position command, multiplied by the ratio of this parameter, is added to the speed command output by the position loop. When the position control command changes smoothly, increasing this gain value can reduce the position following deviation and improve the position followability. When the position control command changes not in a smooth manner, mechanical vibration may occur; reducing this gain value can mitigate vibration. Parameter functions: Set the first-order inertia filtering time constant for speed feedforward gain.
When the position control command changes smoothly, shortening this filtering time can reduce the position following deviation and improve the position followability. When the position control command changes not in a smooth manner, prolonging this filtering time can reduce running vibration of the machine, but the position following deviation will also increase.
127 Technical Manual for EA190 Series Servo Driver V100 P4-04 _ Speed ring differential time constant ASR Td _ Initial value 0.0 _ _ Communication address 0404H Unit ms Time of taking effect With immediate effect Setting range 0.1~3000.0 Data size 16bit Control mode P S P4-05 Speed loop integral time constant ASR Ti _ Initial value 21.0 Communication address 0405H Unit ms Time of taking effect With immediate effect Setting range 0.1~3000.0 Data size 16bit Control mode P S _ P4-06 Speed feedforward gain APR Kp _ Initial value 30.0 Communication address 0406H Unit % Time of taking effect With immediate effect Setting range 0.0~300.0 Data size 16bit Control mode P P4-07 Speed feedforward filtering time constant Initial value 5 Communication address 0407H Unit ms Time of taking effect With immediate effect Setting range 0~100 Data size 16bit Control mode P P4-08 Speed feedback low-pass filtering time constant Initial value 0.00 Communication address 0408H Unit ms Time of taking effect With immediate effect Setting range 0.00~20.00 Data size 16bit Control mode P S