Motion iWMC Series - Tuning Position Loop

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4.2 Tuning Posion Loop
Table 4–2List of posion loop parameters
Internal
address
Name
Descripon
Default
Range
60FB0110
Kpp[0]
Set the posion loop response bandwidth, unit:
0.01Hz
10
0～327
60FB0210
K_Velocity_FF
0 means no feedforward, 1000 means 100%
feedforward.
100
0～100
60FB0310
K_Acc_FF
Under the premise that the inera rao is set
correctly, this parameter can be set, if you do not
know the inera rao, please directly set the
posion loop acceleraon feed forward
(0x60FB03)
/
0-32767
60FB0510
Pos_Filter_N
The smooth acceleraon and deceleraon
process needs to be set in the motor loose sha
state
1
1~255
60650020
Max_Following_Error_16
The maximum allowable error, exceeding the
changed value will alarm 020.0
10000
/
Step of Posion loop tuning is shown below:
Step1: Posion loop proporonal gain adjustment
Increasing posion loop proporonal gain can improve posion loop bandwidth, thus reducing posioning me and
following error, but seng it too high will cause noise or even oscillaon. It must be set according to load condions.
Kpp = 103 * Pc_Loop_BW, Pc_Loop_BW is posion loop bandwidth. Posion loop bandwidth cannot exceed velocity
loop bandwidth. Recommended velocity loop bandwidth: Pc_Loop_BW<Vc_Loop_BW / 4, Vc_Loop_BW.
Step2: Posion loop velocity feedforward adjustment
Increasing the posion loop velocity feedforward can reduce posion following error, but can result in increased
overshoong. If the posion command signal is not smooth, reducing posion loop velocity feedforward can reduce
motor oscillaon.
The velocity feedforward funcon can be treated as the upper controller (e.g. PLC) have a chance to directly control
the velocity in a posion operaon mode. In fact this funcon will expend part of the velocity loop response ability, so
if the seng can’t match the posion loop proporonal gain and the velocity loop bandwidth, the overshot will
happen.