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Quick Start Guide Stabiliti™ Series PCS
MAN-00114, Rev D
power is diverted to DC3, charging the battery. Moving from PV to genset and back again is
blink-less because the DC3 battery will completely support the microgrid during these
Control Method transitions.
NOTE: This use case requires additional hardware and related control mechanisms to
disconnect the PV array and connect the genset into DC2, notably external DC contactors and
an external 3-phase rectifier. This genset integration scheme offers higher quality microgrid
power, compared to traditional AC-coupled solutions.
PV Firming / Demand Management
AC1= GPWR / DC3 = MPPT / DC2 = NET:
This energy flow example uses a PV Array or PV simulator on DC3 with a high-voltage
battery on DC2.
Setting the AC1 GPWR power setpoint to 1500 will export a constant 15 kW to the grid.
“Summing” of PV and battery power occurs when the available solar resource alone cannot
support the commanded AC1 power level (low or highly-variable irradiance).
“Splitting” occurs when the available solar resource exceeds 15 kW. The PV Array
connected to DC2 exports 15 kW to the grid and any excess power available from DC2 is
shunted to DC3 (charging the DC3 battery).
Considerations: During periods of high-irradiance and modest export demand, your system
controller must proactively manage the DC3 battery State of Charge (SoC). This is
accomplished by setting a lower soft-power limit on the DC2 port, curtailing PV power, and
preventing battery overcharging. Adjust the soft power limit higher once batteries are below
max SoC.
Changing the FPWR setpoint to -500 reverses power flow and will charge the battery at a
fixed 5 kW rate. This is a typical overnight charging application with charging power sourced
from the grid.
During the day, if the -500 setpoint remains active, the available solar energy and the 5 kW
charge rate will sum to charge the DC3 battery.
Configure the 30C3 as follows:
1.
Update Port 1 (AC1) registers.
a.
Update register ‘p1_control_method’ to 0x0402 for GPWR method.
b.
Update register ‘p1_ power_setpt’ to desired real power level for grid export.
1500 = 15 kW of real power exported to AC1
Update register ‘p1__reactive_pwr_setpt’ to desired reactive power level
for grid export
0 = 0 kVar of reactive power exported to AC1, or
200 = 2 kVar of reactive power exported to AC1
2.
Update Port 2 (DC2) registers.
a.
Update register ‘p2_control_method’ to 0x0002 for MPPT method.
b.
Update register ‘pv_start_time’ to appropriate start time window (in minutes).
