WEG CFW-09 - Page 203

204
CHAPTER 6 - DETAILED PARAMETER DESCRIPTION
Range
[Factory Setting]
Parameter
Unit
Description / Notes
TheFlyingStartfunctionallows the inverter tostarta motor thatisrunning
freely. This function takes the motor from its actual speed to the speed
reference set at the inverter.
In order to enable the Flying Start function set P320 = 1 or 2.
If the Flying Start function is not needed at some moments, a digital
inputmaybeset todisable the FlyingStart (setonlyoneofthe parameters
between P265 and P270 to 17).
Flying Start for V/F/VVW Control Mode:
To do that it has a voltage ramp (adjusted in P331) and the motor
frequency is fixed and defined by the speed setpoint. The Flying Start
will always work when a start or run command is given, after the time
adjusted in P332 (to allow for the motor demagnetization).
Parameter P331 sets the time required for the output voltage reaching
the rated voltage.
FlyingStart(FS)functionfortheSensorlessVectorControl(P202 = 3)
The Flying Start function takes place after the START command.At this
moment,the inverter sensesthemotorspeed, andonce themotor speed
is found, which may be in the forward or reverse direction, the motor is
accelerated to the speed reference indicated in P001.
Parameters P135, P331 and P332 are not used by the Flying Start
function when P202 = 3.
Settings:
It is recommended to adjust P151 to the value in table 6.8 and P150 to
1.
Ride-Through for V/F Control Mode or VVW:
TheRide-Through functionfor theV/F and VVW ControlModes works in
a different manner than in the Vector Control Mode.
As soon as the line
supply falls to a value lower than the undervoltage (E02) Trip level (refer
toitem 7.1),the IGBTinverterisdisabled(novoltage pulses atthe motor).
There is no tripping due to undervoltage, and the DC Link voltage will
slowly fall until the line supply comes back.
If the linesupplytakes too long to come back (more than2 s)
the inverter
may trip by E02 or E70. If it comes back before, the inverter will start
the motor with a voltageramp like intheFlyingStart function.Thevoltage
ramp time is defined also in P331. Refer to figures 6.44 a) and b).
The parameter P332, used for the Ride-Through function, sets the
minimumtime whichthe inverter willwait to restartthe motor aftervoltage
re-establishment.This timeis computed from thelineloss and is required
for the motor demagnetization. Set this time at two times the motor
rotor constant, refer to table in P412.
TheRide-Throughfunctionallows recovering theinverter withoutE02 trip
(under voltage) during a momentarypower supplyinterruption.
P331
0.2 to 60.0
VoltageRamp
[ 2.0 ]
0.1 s
P332
0.1 to 10.0
DeadTime
[ 1.0 ]
0.1 s
These
parame
t
ers
(
P331
and
P332)
are only
displayed when
P202 = 0, 1, 2 or 5
(V/F / VVW Control)