Lenze 8400 StateLine - Manual (Page 158)

5 Motor control (MCTRL)
5.6 V/f control (VFCplus + encoder)
158
Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14
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5.6.2.1 Parameterising the slip regulator
The slip regulator is designed as a PI controller. In order to improve the response to setpoint
changes, the setpoint speed or setpoint frequency is added to the output (correcting variable) of the
slip regulator as feedforward control value.
• Unlike traditional speed controllers, the slip regulator only controls the slip.
• In the Lenze setting, the configuration of the slip regulator provides robustness and moderate
dynamics.
Slip regulator gain Vp
The setting range of the slip regulator gain Vp (
C00972 ) which leads to a stable operational
performance, mainly depends on the resolution of the speed sensor. There is a direct relationship
between encoder resolution and gain:
• The higher the encoder resolution, the higher the gain can be set.
The following table provides maximum and recommended slip regulator gains for encoder with
standard encoder increments:
[5-1] Slip regulator gain Vp based on the encoder increment
Parameter Info Lenze setting
Value Unit
C00971/1 VFC: Controller limitation V/f +encoder 10.00 Hz
C00971/2 VFC: Slip limitation V/f +encoder 100.00 Hz
C00972 VFC: Vp V/f +encoder 0.100 Hz/Hz
C00973 VFC: Ti V/f +encoder 100.0 ms
Encoder increment
[Increments/revolution]
Slip regulator gain Vp
maximum
recommended
8 0.09 0.06
64 0.52 0.31
100 0.79 0.47
120 0.94 0.57
128 1.00 0.60
256 1.29 0.77
386 1.63 0.98
512 1.97 1.18
640 2.31 1.38
768 2.65 1.59
896 2.99 1.79
1014 3.33 2.00
1536 4.69 2.81
2048 6.05 3.63
3072 8.77 5.26
4096 11.49 6.90