SMA SUNNY ISLAND 8.0H - Generator Management of the Off-Grid Inverter; Generator Management Tasks; Conditions for Generator Requests

SMA Solar Technology AG 10 External Energy Sources in the Off-Grid System
Installation Manual SI80H-60H-OffGrid-IA-en-11 131
10.7 Generator Management of the Off-Grid Inverter
10.7.1 Generator Management Tasks
The generator management performs the following tasks:
• Requesting the generator in automatic generator mode (see Section 10.7.2"Conditions for
Generator Requests",page131):
– Requesting the generator depending on the state of charge
– Requesting the generator depending on the load
– Requesting the generator in a time-controlled manner
– Requesting the generator depending on the charging process
• Controlling the off-grid inverter for switching the stand-alone grid to the generator voltage
(see Section 10.4"Synchronisation of the Stand-Alone Grid to the External Energy
Source",page130)
• Observing generator run times in order to prolong the generator's service life
(see Section 10.7.3"Generator Run Times",page132)
• Protecting the generator against overload and backfeed (see Section 10.7.4"Electrical Limiting
Values for the Generator",page133)
• Controlling the off-grid inverters when disconnecting the generator
• Supplying reactive power for the generator
10.7.2 Conditions for Generator Requests
To adjust generator management to the requirements of the off-grid system, you can change the
conditions for generator requests.
Generator request Explanation
State-of-charge-dependent
generator request
Depending on the state of charge of the battery, the generator
management requests the generator so that it will recharge the
battery. In this way, the generator management prevents the
battery from discharging too much. Tip: You can also configure
the generator request depending on the time of day, e.g. to avoid
starting the generator at night where possible.
Load-dependent generator
request
If the consumption load in the stand-alone grid exceeds a
configured limit, generator management requests the generator.
The generator then supplies the loads. This reduces the load on
the battery.
If necessary, the loads in the stand-alone grid are supplied by the
generator and the off-grid inverter together. The sum of both
powers is available to the stand-alone grid.