Lenze EVF9333−xV - Manual (Page 321)

Configuration
Function blocks
Internal motor control with vector control (MCTRL2)
8
8.2
8.2.7
l
8.2−59 EDSVF9333V EN 6.2−04/2012
A PI controller compares the speed setpoint with the actual speed of the
motor model and creates a torque setpoint from the speed variation.
ƒ the actual speed is output as an analog signal (in [%] of n
max
(C0011))
to MCTRL−NACT.
Parameter setting
Code Function
C0070 Gain V
p
C0071 Integral−action time T
n
Operation with speed feedback
To change over to operation with external speed feedback, the incremental
encoder must be selected via C0025. The external speed feedback serves to
operate the motor in all of the four torque/speed quadrants.
Adaptation of the speed controller
Use the input MCTRL−VP−N−ADAPT to change the gain of the speed controller
online. The set gain in C0070 is the reference value for an input signal of
100 %.
ƒ By adapting a function block (e.g. CURVE) to MCTRL−VP−N−ADAPT you
can influence the gain (C0070).
ƒ In the Lenze setting the adaptation is deactivated.
Behaviour when speed setpoint = 0
If the speed setpoint = 0 (MCTRL−N−SET = 0) and actual speed value
» 0
(MCTRL−NACT
» 0), the speed controller is switched off. The motor merely
receives its magnetising current.
Behaviour in braking operation at very low speed
(
Stop!
A longer−lasting braking operation with very low speed can lead
to an unstable vector control. Remedy:
ƒ Passing through the critical speed range more quickly.
ƒ Using speed feedback.
Speed control