Danfoss VLT AAF006, Руководство по эксплуатации

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mixed loads. Non-linear loads (diode feed loads) must hold
AC coils to protect against overcurrent of the input diodes.
Control
Manual
Disconnect
Fuse
Option
Soft charge
circuit
13
0B
B7
19
.1
0
Illustration 1.3 Block Diagram
The filter allows either overall or selective harmonic
compensation modes. In overall compensation mode, all
harmonics are reduced. In this mode, the filter balances
the load to reduce uneven load distribution among the 3
phases. The steady state performance allows compensation
of harmonics to the 40th order, but the ultra-quick current
injection allows the filter to compensate flicker and other
quick and short-term phenomena. In selective mode, the
user can program acceptable individual harmonic levels
between 5th and 25th order. In selective mode, the filter
does not reduce harmonics in twos and threes, and does
not support phase load balancing and flicker reduction.
See
parameter 300-00 Harmonic Cancellation Mode .
Program the filter priority as either reactive current or
harmonic compensation. If harmonic compensation is first
priority, the filter uses the current needed for harmonic
reduction and uses energy for reactive current correction
only if there is excess. The filter automatically and contin-
uously assigns energy between first and second priority to
provide the highest possible mitigation of both reactive
and harmonic compensation. The power factor is
optimised continuously and the supply transformer is used
to its maximum capacity. See
parameter 300-01 Compen-
sation Priority .
The active filter has an optional RFI filter for Class A1 equal
to category C2.
1.3.2 IEEE519 Compliance
The active filter is designed to meet IEEE519 recommen-
dation for Isc/Il >20 for even individual harmonic levels.
The filter has a progressive switching frequency that
creates a wide frequency spread, giving lower individual
harmonic levels above the 50th harmonic level.
Introduction Operating Instructions
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