Lenze EVS93 Series, System Manual

Page: 237 / 386

Function library
Function blocks
3.2.62 Mains failure control (MFAIL)
3−209
l
EDSVS9332K−EXT EN 4.0
3.2.62.5 Dynamic adaptation of the control parameters
In special cases a dynamic change of the proportional gain may be useful. For this purpose, the
function block MFAIL is provided with two inputs (MFAIL−CONST and MFAIL−ADAPT). The resulting
proportional gain arises from:
V
p
+
C0980
@
MFAIL−CONST
*
|MFAIL−ADAPT|
100%
3.2.62.6 Fast mains recovery (auto reclosure)
The fast mains recovery leads to the restart of the controller if the restart protection is not activated.
Then the drive runs to its setpoint. If this is not desired, the restart can be delayed via the retrigger
time C0983 or prevented in connection with the restart protection.
A fast mains recovery occurs:
l
Due to the system, the mains recovery is indicated by the mains failure detection via the level
of the DC bus voltage (see chapter 3.2.62.1).
l
Because of an "auto reclosure" of the power supply company (e.g. in case of thunderstorms)
l Because of faulty components in the supply cables (e.g. slip rings)
Set the retrigger time C0983 higher than the measured deceleration time during braking.
3.2.62.7 Application example
Drive network with digital frequency coupling
(
STOP!
In drive networks which are coupled via digital frequency (a master and one or more
slaves):
l
The mains failure detection and control may only be activated for the master.
– The mains failure control must be integrated correspondingly into the signal
flow.
l All controllers must be operated via the terUG, −UG in the DC−bus
connection. For this, the information in the "Dimensioning" chapter must be
observed.
)
Note!
Further information and predefined configurations can be obtained from Lenze.