Lenze 8400 - Manual (Page 190)

5 Motor control (MCTRL)
5.7 Sensorless vector control (SLVC)
190
Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
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5.7.4.2 Optimise speed controller
The speed controller is designed as a PI controller.
• In the Lenze setting, the configuration of the speed controller provides robustness and
moderate dynamics.
Speed controller gain Vp
The gain Vp (
C00070/1 ) of the speed controller is defined in a scaled representation which enables
a comparable parameterisation almost independent of the power of the motor or inverter. Here, the
speed input difference of the controller is scaled to the rated motor speed whereas the output
torque refers to the rated motor torque. A gain of 10 means that a speed difference of 1 % is gained
through the P component with 10 % torque.
If the rated data of the motor and the mass inertia of the drive system are known, we recommend
the following setting:
[5-10] Recommendation for the setting of the gain of the speed controller

Tip!
Values recommended by Lenze for the setting of the (proportional) gain:
• For drive systems without feedback: Vp = 6 … 25
• For drive systems with a good disturbance behaviour: Vp > 15
In this case, we recommend the optimisation of the dynamic performance of the torque
controller.
Parameter Info Lenze setting
Value Unit
C00070/1 SLVC: Vp speed controller 15.00
C00071/1 SLVC: Ti speed controller 100.0 ms
V
P
= Gain of the speed controller ( C00070/1 )
T
M
= Time constant for the acceleration of the motor
M
N
= Rated motor torque
n
N
= Rated motor speed
J
drive, total
= Total moment of inertia of the drive
V
P
1.5 ... 3
T
M
s [ ]
0.01 s [ ]
------------------- ⋅ ≈
T
M
s [ ]
2 π n
N
rpm [ ] ⋅ ⋅
M
N
Nm [ ] 60 ⋅
-------------------------------------- J
Drive, total
kgm
2
[ ] ⋅ =
M
N
Nm [ ]
P
N
W [ ] 60 ⋅
2 π n
N
rpm [ ] ⋅ ⋅
-------------------------------------- =