Sunny Island
Installation & Operating Instructions
BWRI33-12:EE
- 116 -
SMA Regelsysteme GmbH
12 Operating Modes
The Sunny Island can be modularly combined with other power sources and must
then operate in different operating modes. This chapter covers both basic grid con-
figurations and the resulting requirements for the Sunny Island and the other compo-
nents in the island grid.
Control of voltage and frequency in the island grid
The Sunny Island can operate in the following operating modes:
•
Grid forming (RUN_U), the Sunny Island keeps the voltage and the frequency
of the grid at a constant level.
•
Grid-tied (RUN_I), the Sunny Island follows the voltage and frequency that is
defined by a further component of the island grid that itself forms the grid.
12.1 Grid-Forming Operation (RUN_U)
In grid forming mode the Sunny Island keeps the grid voltage at a constant sine-
wave voltage and constant frequency. The voltage and frequency is defined in the
“PARGRD“ 3+4 parameters. The Sunny Island then has to provide the necessary
active and reactive power that is required for the control of the grid. All other compo-
nents in the grid then have to operate as grid controlled power generators or con-
sumers.
