Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 36)

36 Rockwell Automation Publication 750-RM002B-EN-P - September 2013
Chapter 1 Drive Configuration
Calculate
When the Autotune parameter is set to Calculate (default), the drive uses motor
nameplate data to automatically set P73 [IR Voltage Drop], P74 [Ixo Voltage
Drop], P75 [Flux Current Ref ] and P621 [Slip RPM at FLA].
P73 [IR Volt Drop], P87 [PM IR Voltage], P79 [Encdrlss VltComp], P74 [Ixo
Voltage Drop], P75 [Flux Current Ref ], P93 [PM Dir Test Cur], and the Slip
Frequency parameters are updated based on nameplate parameter values. When a
nameplate parameter value is changed, the Autotune parameters are updated
based on the new nameplate values.
When using Calculate, updated values come from a lookup table.
Static Tune
When the Autotune parameter is set to Static, only tests that do not create motor
movement are run. A temporary command that initiates a non-rotational motor
stator resistance test for the best possible automatic setting of P73 [IR Voltage
Drop] in all valid modes and a non-rotational motor leakage inductance test for
the best possible automatic setting of P74 [Ixo Voltage Drop] in a Flux Vector
(FV) mode. A start command is required following initiation of this setting.
Used when motor cannot be rotated.
Rotate Tune
The actual tests performed when Static and Rotate Tune selections are made,
differ for the available motor control modes, Feedback Type and motor type
selected. The tests performed are dependent on the settings of P35 [Motor Ctrl
Mode], P125 [Pri Vel Fdbk Sel], and P70 [Autotune]. The parameters that are
updated are then dependent on the tests run and in some cases calculated values
for some parameters are used to update other parameters. Refer to
Table 3 .
A temporary command initiates a Static Tune and is then followed by a rotational
test for the best possible automatic setting of P75 [Flux Current Ref ]. In Flux
Vector (FV) mode, with encoder feedback, a test for the best possible automatic
setting of P621 [Slip RPM at FLA] is also run. A start command is required
following initiation of this setting.
IMPORTANT If using rotate tune for a Sensorless Vector (SV) mode, uncoupled the motor from the
load or results can be invalid. With a Flux Vector (FV) mode, either a coupled or
uncoupled load produces valid results. Caution must be used when connecting the
load to the motor shaft and then performing an autotune. Rotation during the tune
process can exceed machine limits.