Lenze i950 - Page 284

Seng the notch lters
Since the exact frequency response of the speed control path in most cases is not known
be
forehand, an experimental procedure for seng the notch lters is described in the follow-
ing.
How to set the notch lters:
1.
Se
t and opmise current controller, see secon Curr
ent controller .^ 265
2.
Adapt the speed controller reset me to the
lter me constant of the actual speed lter
me and the equivalent me constant of the current control loop:
•
The following applies: 0x2900:002 = 16 * (0x2904 + 500 µs)
Note: The seng of the reset me includes the equivalent me constant of the current
control loop. The 500 μs indicated are typical in a power range of up to 50 kW. Above this
value, greater me constants may occur.
3.
Slowly increase the proporonal gain of the speed controller in 0x2900:001 unl the speed
control loop starts to be unstable (acousc determinaon, measurement of the motor cur-
rent or recording of the speed output signal).
4.
Measure the oscillaon frequency using an oscilloscope:
•
Assessing the motor current via .
•
Assessing the motor speed via 0x6044.
5.
Set the oscillaon frequency determined as lter frequency in 0x2944:001.
6.
Set the
lter width to 40 % of the lter frequency in 0x2944:002.
7.
Se the
lter depth to 40 dB in 0x2944:003.
•
If "0 dB" is set (default seng), the lter is not eecve.
8.
Further incr
ease the
proporonal gain of the speed controller in 0x2900:001 unl the
speed control loop starts to be unstable again.
•
If the oscillaon frequency has changed now, readjust the lter frequency by trimming.
The use of a second lter is ineecve here.
•
If the oscillaon frequency remains the same, readjust the lter depth and/or the lter
width by trimming (the rst reduces the amplitude, the second lets the phase rotate
faster).
•
Repeat step 8 unl the desired behaviour or the limit of a sensible speed controller
gain has been reached.
9.
Check the drive behaviour in case of quick stop (QSP)
•
Accelerate drive
•
Then, brake with quick stop (QSP) and check whether a reduced drive dynamics can be
detected.
•
If so, reduce the inuence of the lters unl the reachable dynamics corresponds to
the requirements.
NOTICE
▶
Readjust the speed controller aer
seng the notch lters (see secon "Speed controller").
^ 262
▶
Save the changed sengs.
▶
The »EASY Starter« serves to save the parameter sengs of the servo inverter as parameter
le (*.gdc), see secon Saving the parameter sengs . ^ 36
Parameter
Address Name / seng range / [default seng] Info
0x2944:001 Torque setpoint notch lter: Frequency notch lter 1
1.0 ... [200.0] ... 1000.0 Hz
Seng of the frequency for notch lter 1.
0x2944:002 Torque setpoint notch lter: Bandwidth notch lter 1
0.0 ... [20.0] ... 500.0
Hz
Seng of the bandwidth for notch lter 1.
0x2944:003 Torque setpoint notch lter: Damping notch lter 1
0 ... [0] ... 100 dB
Seng of the damping for notch lter 1.
0x2944:004 Torque setpoint notch lter: Frequency notch lter 2
1.0 ... [400.0] ... 1000.0 Hz
Seng of the frequency for notch lter 2.
Conguring the motor control
P
arameterise lter elements in the setpoint path
Notch lter (band-stop lter)
284