DC micro grid control system based on intelligent power units

In this paper a compact all-in-one DC Micro Grid Control System is presented. The system is based on a novel modular approach using intelligent power units. The DC Micro Grid Control System comprises a 3.7 kW insulating bidirectional AC/DC converter, two 3.7 kW DC/DC converters for MPPT tracking of two independent PV-strings and a 7.4 kW bidirectional DC/DC converter for connecting a high voltage battery stack. It will be shown that by using intelligent power units with a 2-wire interface for integrated signal and power transfer the system design becomes much easier and an overall compact and lower cost power electronic design can be achieved.