1 Introduction

DC microgrids are localized energy systems operating from a DC bus within a defined voltage range. These systems can vary greatly in size and power, from small islands with several motors on a shared DC bus up to large-scale applications, such as entire factories or data centers with combined loads reaching up to the megawatts. While smaller island systems can extend existing factory infrastructures, larger installations significantly benefit from the economies of scale, achieved through their shared infrastructure. These larger DC grids facilitate more efficient integration of renewable energy sources, such as solar and wind, and enhance energy management, especially in industries with a high number of dynamic loads and increasing amounts of energy storage.

Additional components in a DC microgrid besides the AC/DC grid connection, renewables, battery systems and various loads include circuit breakers, precharge units, monitoring systems and auxiliary supplies for attached systems. Figure 1-1 shows a DC microgrid and possible system blocks.

Figure 1-1 Components and Loads in a DC Microgrid

This technical white paper provides an overview of the advantages of DC over AC power grids; a description of DC microgrids; and an exploration of their applications in factory automation, data centers and building automation. We also explore how innovative semiconductors are enabling the transition to DC microgrids by enhancing isolation measurement systems, power supplies and solar inverters.