SMA SC 500HE-20 - Manual (Page 29)

SMA Solar Technology AG 3 Product Description
Operating Manual SCxxxHE-20-BE-BEN111210 29
3.6.2 Active Power Limitation
Five methods are available for limiting the active power regardless of power frequency. The limit can
be defined using a parameter and supplied by the grid operator via an external signal.
In addition to these methods, the active power can also be limited according to the power frequency.
3.6.3 Reactive Power Setpoint
The Sunny Central can provide reactive power. There are 11 methods for specifying the reactive
power setpoint. They include entering a fixed parameter, processing an external signal from the grid
operator or specifying the reactive power using characteristic curve parameters.
3.6.4 Dynamic Grid Support (FRT)
The Sunny Central can support the grid during a grid voltage drop by supplying reactive power.
3.6.5 Decoupling Protection Ramp
After a grid fault, the Sunny Central restarts at a maximum 10% of nominal power per minute using
a decoupling protection ramp. You have the option of switching this decoupling protection ramp on
or off.
If you switch the decoupling protection ramp off, the Sunny Central quickly returns to maximum
power.
If you wish to deactivate the decoupling protection ramp, consult the SMA Service Line.
3.6.6 Grid Management Shutdown
If the power grid becomes unstable and overloaded, grid management requires that the inverter
disconnect from the grid immediately. In such cases the relevant signal will be sent by the grid
operator or the transfer point safety system. The inverter disconnects from the grid immediately and
displays error 9013.
The error will be reset in the inverter after a signal is sent by the grid operator of transfer point safety
system.
3.7 Active Islanding Detection
The active islanding detection function detects the formation of island grids during a grid failure and
disconnects the Sunny Central from the grid.
Stand-alone grids form when the following conditions are present at the same time:
• The medium voltage grid fails
• The Sunny Central feeds in x amount of power
• There is a consumer on the same branch of the grid with a load equal to x amount of power
To enable the active islanding detection, contact the SMA Service Line.