These inverters have been developed for the microgrid Bronsbergen in Zutphen, the Netherlands. The microgrid was originally created in as a full-scale test site within the MORE MICROGRIDS project of the European 6th Framework Program.
The control systems of the inverters enable seamless transition from grid-connected to islanded operation and automatic load sharing between inverters without any communication link or master-slave function. The inverters can supply a fault current of 4 times their rated current, in order to ensure selectivity of the network’s protection systems during islanded operation.
In order to accommodate the typically asymmetric load of an LV distribution network, the neutral connection of the inverter can be loaded with the full rated phase current. All auxiliary power is generated directly from the battery voltage using a separate power supply, so that the inverter can be used for black starting the microgrid.
The inverters feature active compensation of harmonics up to 450 Hz and passive damping of harmonics up to 750 Hz. This is used to improve the power quality of the local network, which includes approx. 300 kW of residential PV systems.
