A qualitative overview of different hardware topologies and control systems for DC MGs has been presented in this chapter. Some challenges and design considerations of DC protections systems have also been discussed. Finally, applications of DC MGs in emerging smart grid applications have been summarized. Due to its attractive characteristics in terms of compliance with modern generation, storage and electronic load technologies, high reliability and current carrying capacity, as well as simple control, DC systems are already an indispensable part of power systems. Moreover, the existing challenges such as protection issues will be effectively resolved in the near future due to fast progress of semiconductor technology which is a key enabler cheap and reliable future DC solid-state protection systems. Therefore, it is the view of the author that more and more DC systems will appear in different industries and gradually lead to new ways of rethinking of the future power distribution philosophies, especially with the emergence of SSTs. Research in DC systems, especially in the power electronics-based technologies will be highly attractive in the future.

Chapter Contents:

• 7.1 Introduction
• 7.2 DC microgrid system overview
• 7.2.1 Single-bus topologies
• 7.2.2 Multi-bus topologies
• 7.2.3 Reconfigurable topologies
• 7.2.4 Hybrid AC/DC MGs
• 7.3 Operation and control of DC microgrids
• 7.3.1 Local control functionalities
• 7.3.2 Coordinated control
• 7.3.2.1 Centralized coordination
• 7.3.2.2 Decentralized coordination
• 7.3.2.3 Distributed coordination
• 7.4 DC microgrid system protection
• 7.4.1 Types of faults
• 7.4.2 Grounding
• 7.4.3 Protective devices
• 7.4.4 Design of protection systems
• 7.5 Application of DC microgrids to future smart grids
• 7.5.1 High-efficiency households
• 7.5.2 Renewable energy parks
• 7.5.3 Hybrid ESS
• 7.5.4 EV fast charging stations
• 7.6 Conclusions
• References

Inspec keywords: power generation control; power distribution control; distributed power generation

Other keywords: DC distribution systems; DC protections systems; storage load technology; power electronics; semiconductor technology; DC microgrids; current carrying capacity; hardware topology; modern generation; control systems; smart grid; electronic load technology

Subjects: Control of electric power systems; Power system control; Distributed power generation