Power Factor - Danfoss VLT AutomationDrive FC 300 Design Manual

How to Read this Design Gui...
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THD
Total Harmonic Distortion. A state of full harmonic
distortion.
Trip
A state entered in fault situations. For example, if the
adjustable frequency drive is subject to an overtem-
perature or when it is protecting the motor, process, or
mechanism. Restart is prevented until the cause of the
fault has disappeared and the trip state is canceled by
activating reset or, in some cases, by being programmed
to reset automatically. Do not use trip for personal safety.
Trip Locked
A state entered in fault situations when the adjustable
frequency drive is protecting itself and requires physical
intervention. For example, if the adjustable frequency drive
is subject to a short circuit on the output, it will enter trip
lock. A locked trip can only be canceled by cutting off line
power, removing the cause of the fault, and reconnecting
the adjustable frequency drive.
VT Characteristics
Variable torque characteristics used for pumps and fans.
plus
VVC
Compared with standard voltage/frequency ratio control,
Voltage Vector Control (VVC
and stability, both when the speed reference is changed
and in relation to the load torque.
60° AVM
Switching pattern called 60° Asynchronous Vector
Modulation (See 14-00 Switching Pattern).
14
Design Guide
plus ) improves the dynamics
Danfoss A/S © Rev. 2014-02-10 All rights reserved.

1.7 Power Factor

The power factor is the relation between I
3 × U × I 1 × COS ϕ
Power factor =
3 × U × IRMS
The power factor for 3-phase control:
I × cos ϕ1 I
1 1
= = since cos ϕ1 = 1
I I
RMS RMS
The power factor indicates to what extent the adjustable
frequency drive imposes a load on the line power supply.
The lower the power factor, the higher the I
same kW performance.
I 1 2 I 5 2 I 7 2 I n 2
IRMS
= + + + . . +
In addition, a high power factor indicates that the different
harmonic currents are low.
The built-in DC coils produce a high power factor, which
minimizes the imposed load on the line power supply.
and I .
1 RMS
for the
RMS
MG34S222