Kinco CD430 - Page 48

48
Current loops are related to motor parameters (optimal parameters of the selected motor are default for
the driver and no adjusting is required).
Parameters for velocity loops and position loops should be adjusted properly according to loading
conditions.
During adjustment of the control loop, ensure that the bandwidth of the velocity loop is at least twice of
that of the position loop; otherwise oscillation may occur.
Table 7-5 Parameters for gain control on position loops
Numeric
Display
Variable Name
Meaning
Default
Value
Range
d2.07
Kpp
Indicates the proportional gain of the
position loop Kpp
1000
0~16384
d2.08
K_Velocity_FF
0 indicates no feedforward, and 256
indicates 100% feedforward
256
0~256
d2.09
K_Acc_FF
The value is inversely proportional to the
feedforward
32767
32767~10
d0.05
Pc_Loop_BW
Sets the bandwidth of the position loop in
Hz.
0
/
Proportional gains of the position loop Kpp: If the proportional gain of the position loops increases, the
bandwidth of the position loop is improved, thus reducing both the positioning time and following errors.
However, too great bandwidth may cause noise or even oscillation. Therefore, this parameter must be set
properly according to loading conditions. In the formula Kpp=103* Pc_Loop_BW,Pc_Loop_BW indicates the
bandwidth of the position loop. The bandwidth of a position loop is less than or equal to that of a velocity loop.
It is recommended that Pc_Loop_BW be less than Vc_Loop_BW /4 (Vc_Loop_BW indicates the bandwidth of
a velocity loop).
Velocity feedforward of the position loop K_Velocity_FF : the velocity feedforward of a position loop can be
increased to reduce position following errors. When position signals are not smooth, if the velocity
feedforward of a position loop is reduced, motor oscillation during running can be reduced. Acceleration
feedback of the position loop K_Acc_FF (adjustment is not recommended for this parameter): If great gains of
position loops are required, the acceleration feedback K_Acc_FF can be properly adjusted to improve
performance.
* * _
K_Acc_FF
250000* 2 * *
pt
t
I K Encoder R
J 

Note: K_Acc_FF is inversely proportional to the acceleration
feedforward.
Table 7-6 Parameters for gain control on position loops
Numeric
Display
Variable Name
Meaning
Default
Value
Range
d2.01
Kvp
Sets the response speed of a velocity loop
100
0~3276
7
d2.02
Kvi
Adjusts speed control so that the time of minor
errors is compensated
2
0~1638
4
d2.05
Speed_Fb_N
You can reduce the noise during motor operation
by reducing the feedback bandwidth of velocity
loops (smoothing feedback signals of encoders).
45
0~45