Eaton DC1-12011 Series, Руководство пользователя

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2 Engineering
2.2 Electrical power network
DC1 Frequency Inverter 10/12 MN04020003Z-EN www.eaton.com
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2.2.5 Idle power compensation devices
Compensation on the power supply side is not required for the frequency
inverters of the DC1 series. From the AC power supply network they only
take on very little reactive power of the fundamental harmonics
(cos
ϕ ~ 0.98).
2.2.6 Mains chokes
Main chokes (also known as commutating chokes) increase the inductance
of the mains supply cable. This extends the current flow period and dampens
mains voltage drops.
These reduce the total harmonic distortion, the mains feedback and improve
the power factor. The apparent current on the mains side is then reduced by
around 30 %.
Towards the frequency inverter, the main chokes dampen the interference
from the supply network. This increases the electric strength of the fre-
quency inverter and lengthens the lifespan (diodes of the mains power recti-
fier, internal DC link capacitors).
￫
In the AC power networks with non-choked reactive current
compensation devices, current deviations can enable parallel
resonance and undefinable circumstances.
In the project planning for the connection of frequency inverters
to AC supply systems with undefined circumstances, consider
using main chokes.
￫
For the operation of the DC1 frequency inverter, the application
of main chokes is not necessary. We do recommend however
that an upstream mains choke is used since the network quality
is not known in most cases.
While planning the project, consider that a main choke is only
assigned to a single frequency inverter for decoupling.
When using an adapting transformer (assigned to a single fre-
quency inverter), a main choke is not necessary.
Main chokes are designed based on the mains-side input cur-
rent (I
LN
) of the frequency inverter.
The main chokes assigned to the DC1 frequency inverter are
listed in the appendix (
￫ Table 25 and ￫ Table 26).