gefran TPD32-EV-...-2B, Instructions Manual, Page: 493 / 504

—————— Instruction manual ——————
493
A2.5 External Three-phase Field Exciter Control
CONFIGURATION
[...] ....
[1522] En ext digit FC
[914] CU EN Flux fact
Parameter No. Format
Value Access via
min max Factory Keyp.
RS485/
BUS/
Opt2-M
Term.
Opt2-A/
PDC
CONFIGURATION
En ext digit FC 1522 I16 0 1 0
ü
R/Z - -
CU EN Flux fact [%] 914 U16 10 100 50
ü
R/Z - -
En ext digit FC
With this function, enabling
En ext digit FC
and the
Flux reg mode
(IPA 469) parameter
can be set to Ext digital FC to use the drive in the "FC" configuration (via fiber optics)
to control the excitation circuit of large DC motors.
CU EN Flux fact
In order to avoid possible armature spikes current during bridge reversing, this value (in
percentage of field current) defines a threshold for activating armature current during
the reverse.
Communication between the TPD32-EV armature control drive (master) and the TPD32-EV-FC drive (slave)
should be via optical fibre serial interface (PAR 469 Flux reg mode = [3] Ext digital FC ) or (from TPD32-EV
FW11.XX, version) by standard external I/O terninal connection (PAR 469
Flux reg mode
= [4]
Ext wired FC
).
In this operating mode, the -FC slave drive acts as an actuator of a current reference from the master control unit.
The master control unit provides the flux reference (voltage regulator output) which, appropriately scaled and
sent to the current reference of the -FC slave drive, enables this to control the current of the three-phase bridge
of the drive connected to the motor excitation circuit (in both the constant torque and constant power areas)
Dynamic control of four-quadrant systems is also possible with a two-quadrant power and control circuit (in
the 2B+e configuration) connected to the armature: this is done by inverting the polarity of the excitation circuit
current connected to a four-quadrant bridge.
In this configuration the slave drive works in torque regulation mode with the reference controlled by the master:
the drive size and, above all, the value of
Full load current
(IPA 179) must therefore be selected according to
the current required by the excitation circuit.
The sign of the master speed regulator output manages the polarity of the current reference sent to the slave:
this is inverted when the value of the speed regulator output is higher than the symmetric hysteresis value set
in [1522] FC cur ref hyst .
This parameter can be used to avoid continuous reversals of field current polarity when the motor is running
with no load applied and thus with a Speed reg output value that is almost null.
If this configuration is enabled, the “Field loss” control indicating the absence of excitation is activated when:
• the master drive is enabled,
• the -FC slave drive is not powered or not enabled or in an alarm condition.
In this operating mode, there is no need to set the field circuit parameters, apart from those to configure any
voltage regulator gains (
Voltage P
IPA 493 and
Voltage I
IPA 494).
i
mPortant
:
if this function is enabled with the 2B+e option, the drive cannot be used with the Speed fbk
sel
parameter (IPA 414) set to
Armature
.