Technical data

PV
OFF GRID
48|48|
|49
Steca Elektronik GmbH | 87700 Memmingen | Germany | Fon [phone] | Fax [phone] | www.stecasolar.com
Three-phase
hybrid system concept
The control concept is similar to that of the sin-
gle-phase system. If more than one Tarom/Power
Tarom are employed, one of the devices must be
designated as the master Tarom. All other charge
controllers are then automatically designated as
slave Taroms. The master Tarom/Power Tarom is
connected directly to the battery, whilst all slaves
are connected to the DC bus. Only the master Ta-
rom/Power Tarom shows the correct charge sta-
tus on its display and controls the energy flow
around the system. Slave Taroms/Power Taroms
perform the function of controlling the charging
from the connected PV modules.
In order to assemble a three-phase energy supply,
three inverters are connected to the DC bus. To
allow three-phase operation the inverters must
be specially designed. Various three-phase gene-
rators can be connected to the three inverters for
controlled recharging of the battery via a PA 15
and a relay. These may be wind, water, or diesel
generators, or the public grid. Suitable inverters
with integrated battery chargers in three-phase
mode are the Steca Xtender devices, which can
be employed from 12 V/3 kW to 48 V/24 kW per
phase. In total, a maximum of 72 kW can be sup-
plied.
Both single-phase and three-phase hybrid system
concepts are based on the same principles of en-
ergy management. With the help of the Steca PA
HS200 current sensor, the charge and discharge
currents of the components, such as slave Ta-
roms/Power Taroms, inverters, etc., are determi-
ned and communicated to the master Tarom/Po-
wer Tarom. Based on the calculated charge status
of the battery, the Steca PA 15 switches the ex-
tra generator on or off. The three single-phase
inverters switch off if the voltage falls below a
given threshold to protect the battery from deep
discharge.
Important features
Combination of different power sources like PV,
wind, diesel generators, etc.
24 h / d full 3 phase 400 V~ and single phase
230 V~ power supply
12 V / 24 V or 48 V overall DC-bus
Automatic energy management regulation based
on the State of Charge of the battery. Including
automatic start of controllable power sources like
e. g. diesel generators
Optimised battery charging algorithm
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Generator
Solar Charge
Controller
Steca
Power Tarom
Steca
PA Tarcom
Battery Battery Battery Battery
3 x
Inverter
Steca Xtender
400 V
Steca
PA 15
Steca
PA HS200
Diesel-
generator
Grid
Wind
Steca
PA 15
3 x
Inverter
Steca Xtender