WEG CFW-11 Series, Руководство по программированию

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Functions Common to All the Control Modes
12-16
12
P0331 – Voltage Ramp
Adjustable
Range: 0.2 to 60.0 s Factory
Setting: 2.0 s
Properties: V/f and VVW
Access groups
via HMI: 01 PARAMETER GROUPS
44 FlyStart/RideThru
Description:
This parameter sets the necessary time for the output voltage to reach the rated voltage value.
It is used by the Flying Start function as well as by the Ride-Through function (both in V/f and VVW mode), together
with the parameter P0332.
P0332 – Dead Time
Adjustable
Range: 0.1 to 10.0 s Factory
Setting: 1.0 s
Properties: V/f and VVW
Access groups
via HMI: 01 PARAMETER GROUPS
44 FlyStart/RideThru
Description:
The parameter P0332 sets the minimum time that the inverter will wait to activate the motor again, which is
necessary for the motor demagnetization.
In the Ride-Through function case, the time is counted starting from the line drop. However in the Flying Start
function actuation, the counting begins after the "Run/Stop = Run" command is given.
For the correct operation, this time must be adjusted to twice the motor rotor constant (refer to the Table 11.7 on
page 11-27 in the Item 11.8.5 Self-Tuning [05] and [94] on page 11-23 ).
12.7.4 Vector Ride-Through
Different from the V/f and VVW mode, in the vector mode the Ride-Through function tries to regulate the DC
link voltage during the line failure, without interruption or fault storing. The energy necessary to keep the inverter
in operation is obtained from the motor kinetic energy (inertia) by means of its deceleration. Thus, at the line
return the motor is reaccelerated to the speed defined by the reference.
After the line failure (t0), the DC link voltage (U
d
) starts diminishing according to a rate depending on the motor
load condition, being able to reach the undervoltage level (t2) if the Ride-Through function is not working. The
typical necessary time for this to occur, with rated load, is from a magnitude of 5 to 15 ms.
With the Ride-Through function active, the line loss is detected when the U
d
voltage reaches a value below the
"DC Link Power Loss" value (t1), defined at the parameter P0321. The inverter initiates a controlled deceleration
of the motor immediately, regenerating energy to the DC link in order to keep the motor operating with the U
d
voltage regulated at the value "DC Link Ride-Through" (P0322).
In case that the line does not return, undervoltage fault will occur - F021 (at t5). If the line returns before the
undervoltage occurrence (t3), the inverter will detect its return when the Ud voltage reaches the "DC Link Power