Technical Manual for EA350 Analog Pulse Type Servo Driver V101 8.9 P4-xx Gain parameters Parameter functions: Select the gain adjustment mode. The letter H at the end of the number means the parameter value is expressed in hexadecimal, and shall be noted during communication. P4-00=0: Manual mode Parameters relating to position loop and speed loop gains and the load inertia ratio are set by the user. In this mode, the control loop coefficient P4-14 is invalid. When the automatic mode is switched to the manual mode, the gain parameter will maintain the value calculated in the original automatic mode. Gain switching is only valid in this mode. P4-00=1 :
Semi-automatic adjustment mode (rigidity table) Applicable in scenarios of basically constant load-inertia ratio When this mode is used, the user shall first perform offline inertia identification by AF-05; when identification is successfully completed, the identification result will be written to the parameter P4-10 and saved (if inertia identification is impossible, the user shall assign a value to P4-10 generally based on the mechanical conditions).
The user needs to select an appropriate rigidity (P4-01) based on the mechanical conditions; the system will, based on the rigidity so selected and the value of P4-10, automatically calculate relevant gain parameters, including P4-02, P4-03, P4-05 and P4-29; meanwhile, these parameters will become read-only. P4-00=2 : Automatic adjustment mode 1 Applicable to scenarios with frequent change of the load inertia ratio (the inertia ratio changes from the smallest to the largest in tens of seconds or longer). When this mode is used, the servo will monitor the change of the load inertia in real time, and write the identification result to parameter P4-10 every 30 minutes.
The user needs to select an appropriate rigidity (P4-01) based on the mechanical conditions; the system will, based on inertia value obtained through online identification each time, automatically calculate relevant gain parameters, including P4-02, P4-03, P4-05 and P4- 29; meanwhile, these parameters will become read-only. P4-00=3: Automatic adjustment mode 2 Similar to automatic adjustment mode 1, but it is more applicable to scenarios with second-level variation of the load inertia ratio. P4-00=4: Automatic adjustment mode 3 Similar to automatic adjustment mode 1, but it is more applicable to scenarios with second-level variation of the load inertia ratio.
In the following circumstances, the manual mode shall be used: ➢ When use of the automatic mode cannot render desirable effect. ➢ When mechanical parts are not firmly connected due to presence of reverse clearance or otherwise, and when the mechanical rigidity is extremely low. ➢ When the load inertia ratio is too high (exceeding 20 times) or too low (less than 3 times), or when the load inertia fluctuates. ➢ When operation continues at a low speed (less than 100rpm), or when the speed of no less than 100rpm and the acceleration of no less than 2,000rpm/s fail to last for at least 50ms.
➢ When the acceleration/deceleration is smaller than 2,000rpm/s, and the acceleration/deceleration torque is smaller than the friction torque. Parameter functions: Select the rigidity grade. The following table shows the relation between rigidity setting and gain parameters. The greater the rigidity value is, the quicker the servo response is; yet excessive rigidity may cause vibration and other abnormalities.
152 P4-00 Selection of gain adjustment mode Initial value 1 Communication address 0400H Unit - Time of taking effect With immediate effect Setting range 0~4 Data size 16bit Control mode P S T P4-01 Rigidity Initial value 13* Communication address 0401H Unit - Time of taking effect With immediate effect Setting range 1~31 Data size 16bit Control mode P S T P4-02 P4-03 P4-05 P4-29 P4-01 Position loop proportional Speed loop proportional Speed loop integral time Torque command low-pass gain 1/s gain, Hz constant, ms smoothing constant, ms 1 2.5 2.0 280.0 11.00 2 3.0 2.5 220.0 9.00 3 4.0 3.0 190.0 8.00 4 4.5 3.5 160.0 6.00 5 5.5 4.5 120.0 5.00 6 7.5 6.0 90.0 4.00 7 9.5 7.5 70.0 3.00 8 11.5 9.0 60.0 3.00 9 14.0 11.0 50.0 2.00 10 17.5 14.0 40.0 2.00