Lenze 8400 StateLine - Manual (Page 223)

Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14
223
5 Motor control (MCTRL)
5.10 Encoder/feedback system
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5.10.2 Generation of the actual speed value
Up to and including version 11.xx.xx the following applies:
• For motor control types without speed feedback ( C00495 = "0: No encoder") a speed-
proportional unit is taken for calculating the nMotorSpeedAct_v speed signal. This derivation,
however, is very imprecise so that in case of applications with synchronous motors without
speed feedback it is not possible to calculate the current position from the current
nMotorSpeedAct_v speed signal.
• The dnMotorPosAct_p position signal is always derived from the nSpeedSetValue_a speed
setpoint. This derivation, however, is very imprecise since in this case, speed limitations (e.g. by
overcurrent limitations) are not considered.
From version 12.00.00 the following applies:
• For applications with synchronous motors without speed feedback, an nMotorSpeedAct_verror-
free speed signal is available. This is calculated from the electrical output angle considering the
number of pole pairs of the nMotorSpeedAct_v speed signal.
• When synchronous or reluctance motors without feedback are used in the motor control types
V/f characteristic control (VFCplus) and Sensorless control for synchronous motors (SLPSM) , the
nMotorSpeedAct_v speed signal can be used to create an error-free position signal via a control
if the nMotorSpeedAct_v signal is read out by the control in a 1 ms cycle.
• The speed signal for deriving the dnMotorPosAct_p position signal can now be selected in
C00490 . In the Lenze setting, the position signal is continued to be derived from the
nSpeedSetValue_a speed setpoint. If, however, "10: No encoder: C495 or nMotorSpeedSetAct_v"
is selected, the position signal is either calculated from the set speed feedback (if C00495 > 0) or
from the nMotorSpeedAct_v speed signal (if C00495 = 0).
• For all motor control types without speed feedback, this selection serves to improve the
creation of the dnMotorPosAct_p position signal.
• When synchronous or reluctance motors without feedback are used, the dnMotorPosAct_p
position signal can be created correctly.
• In case of the motor control types with speed feedback, the dnMotorPosAct_p position signal
is directly created from the speed feedback signal.