Table of Contents
Advertisement
32
H I P E R G U A R D M V U P S U S E R M A N U A L
3.3.2 Auxiliary power supply enclosure (APS)
The APS has centralized power supply bus (N+1) distributed to different functions of the MV UPS enclosures.
The APS is an enclosure that contains:
• switched-mode power supplies,
• digital inputs and outputs,
• auxiliary transformer,
• float charger for energy storage,
• ethernet connections,
• switchgear control interface connections.
3.3.2.1 Auxiliary charger
The PEBBs provide a fast replenishment of energy following a power quality event. To optimize the energy
efficiency during normal operation conditions, an auxiliary charger is used to control the state of charging
of the energy storage. The auxiliary charger is also responsible to pre-charge the DC bus following a shut-
down of the HiPerGuard MV UPS.
3.3.3 Medium Voltage Magnetics enclosure (MVM)
This is the medium voltage section of the HiPerGuard MV UPS that includes the coupling transformer and the line
reactor. The coupling transformer connects the low voltage power converters to the medium voltage network. The
isolating line reactor, which is a 50% impedance, isolates the coupler transformer and the load from the utility.
The magnetics are designed to be air forced cooling. The redundant fans (N+1) draw the air from the bottom of
the cabinet and then push the filtered pressurized air through the magnetics. The heated air is then expelled from
the top of the cabinet. A control and monitoring module located in the MVM (shown in Figure 3.27) is connected to
the APS enclosure via an Ethernet communication cable.
The module has the following functions:
• monitor the temperature of the transformer windings,
• monitor the inlet and exhaust air temperatures,
• control the speed of the fans,
• monitor the correct operation of the fans,
• transmit temperature and fan status information to the main controller.
—
Figure 3.27: Medium
Voltage Magnetics
Enclosure (MVM)
—
Figure 3.25: Auxil-
iary power supply
enclosure (APS)
—
Figure 3.26: Aux-
iliary Charger)
Advertisement
Table of Contents
