Huawei LUNA2000 - Grid-Tied and Off-Grid ESS; Grid-Tied and Off-Grid ESS Networking

2 kW power, the loads consume 4 kW power, and the batteries discharge to supply
1 kW po
wer to the loads.
(2) Set power consumption peak hours (18:00 to 22:00) as the discharge time.
During this time, the batteries discharge. During other periods, such as
00:00-18:00 and 22:00-24:00, surplus PV energy can be used to charge the
batteries, and the batteries do not discharge. When the load power supply is
insucient, the grid supplies power to the loads. For example, when the sunlight
is insucient, the PV module outputs 3 kW power, the loads consume 5 kW
power, and the grid supplies 2 kW power to the loads.
Fully Fed to Grid
● This mode applies to the grid-tied scenario where PV energy is fully fed to the
grid.
● This mode maximizes the PV energy for grid connection. When the generated
PV energy in the daytime is greater than the maximum output capability of
the inverter, the batteries are charged to store energy. When the PV energy is
less than the maximum output capability of the inverter, batteries discharge
to maximize the output energy of the inverter to the grid.
● In this mode, Fully fed to grid is selected. For details, see 6.3 Battery
Commissioning.
Example of fully fed to grid:
For example, when the PV modules generate 8 kW power, the SUN2000-5KTL
inverter connects to the grid with the maximum output power of 5.5 kW, and the
batteries charge 2.5 kW power. When the sunlight becomes weak, the PV modules
generate 3 kW power, the batteries charge 2.5 kW power, and the inverter
connects to the grid with the maximum output power of 5.5 kW.
3.2 Grid-tied and O-grid ESS
The grid-t
ied and o-grid ESS is mainly used to supply power to loads when the
grid is unstable and ther
e are primary loads. The grid-tied and o-grid ESS
switches the inverter to the grid-tied or o-grid state through the Backup Box.
When the grid fails, the inverter switches to the o-grid state and supplies power
to primary loads in backup mode. When the grid recovers, the inverter switches
back to the grid-tied state.
3.2.1 Grid-tied and O-grid ESS Networking
Net
working 1: Inverter + Batteries
The grid-tied and o-grid ESS consists of the PV strings, LUNA2000 batteries,
inv
erter, AC switch, load, Backup Box, PDU, and grid. The grid connection status of
the inverter is switched by using the Backup Box.
LUNA2000-(5-30)-S0
User Manual 3 Application Scenarios and Settings
Issue 01 (2020-10-20) Copyright © Huawei Technologies Co., Ltd. 28