Studer RCC-02, Руководство пользователя

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Studer Innotec SA
RCC-02/-03
User manual
V4.4.0
73
14.15 G
RID
-
FEEDING
{1522}
It is possible under some conditions to feed the grid with energy (AC-In). The following options allow
you to control the different parameters involved.
14.15.1 Grid-feeding authorized {1127}
This parameter allows to authorize or not the grid-feeding. By default setting the grid-feeding is not
authorized. In that case, no energy is sent back to the grid, whatever the operating mode of the
Xtender.
The basic grid-feeding function maintains the battery charged at the standard cycle voltage
(absoption, floating, …). If there is excess energy in the batteries then power is sent to the grid. Per
example for an installation connected to a grid with battery full, if a solar charger connected to the
battery raises the voltage, grid-feeding is done to maintain voltage at the floating level.
14.15.2 Maximum grid-feeding current {1523}
This parameter allows setting a limit for the grid-feeding current. Whatever the setting of this
parameter, the maximum current of the source is respected {1107} (Input limit).
Frequency limit
The grid-feeding is reduced linearly when the
frequency is above the nominal frequency of
the inverter. Until the reference user
frequency attains {1112} +1Hz the grid-
feeding
is maximal and at user
fr2Hz the grid-feeding current is
zero. In a 50Hz system, the grid-feeding is
typically maximal at 51Hz or below, is half at
51.5Hz and zero at 52Hz and above.
This behaviour is used to be compatible with
frequency shift power control in off-grid
systems.
Voltage limit
Grid-injecting inverters have a protection that limits their power when the grid voltage is too
high due to important impedence of the line.
If the voltage exceeds the user reference voltage defined by parameters {1286} and {1433},
the grid feeding current is reduced. The default values of these parameters are typically set
to 230V {1286} and 10V {1433}. Thus the grid feeding is reduced when the voltage is over 240V.
If the grid is always at 250V the inverter will not inject at all according to the parameter {1286}
and {1433}, that stops injecting over 230+10V.
The injected power corresponds to the power of the converter and will be divided between
AC-In and AC-Out depending on the loads. Adding an output load will therefore reduce
the amount of injected current to the grid.