Faculty of Engineering


Research Highlights

Digitalization in Power Distribution

In recent times, various types of power sources are installed in a dispersed manner throughout power distribution systems. For example, photovoltaic cells, fuel cells, and energy storages have become familiar additions to homes and buildings. Multiple batteries, whose voltages are regulated at different ratings, can be found in robots, electrical vehicles and electrical aircrafts.

To effectively manage electricity in these systems, the concept of an “Energy Internet” or “Internet of Energy” has recently been proposed, and is gaining interest. In this proposal, a flow of electrical power is bi-direction; not only flowing from power plants to consumers, but also from consumers with dispersed power sources such as PVs, who sometimes “upload” their power to the power system, thus the comparison to the structure of the internet.

Prior to the proposal of this concept, an Open-Electric-Energy Network (OEEN) was already proposed in the 1990s, in which power flow is controlled by multiple electric-energy routers. This OEEN concept was one of the precursors to the concept of an energy internet. However, at that time the concept was far from the reality because of the lack of the development of power devices, communication systems, and storage devices. Extending this concept much further, Dr. Takahashi and his collaborators have recently proposed and developed a power packet dispatching system utilizing new, highly developed ICT technologies and wide-bandgap power devices such as SiC and GaN. In this system, the power is converted to pulse power with an information tag that is physically attached to its voltage waveform (Fig. 1). It is then delivered on power lines in units of packets. This power packet dispatching system can control power flow in a power distribution network consisting of routers for the power packets (Fig. 2). This system has a potential to realize “energy on demand,” which implies each load demands as much power as necessary from an appropriate power source in the system. In addition, the system permits expandability and flexibility; power sources and loads can be attached/removed to the system as units. Therefore, this power packet dispatching system has the potential to become an effective energy management system in cases where space and the capacities of installed multiple power sources are limited, i.e, closed systems such as robots, electrical vehicles and electrical aircraft. Homes, buildings, and communities are also possible candidates for the adoption of this power packet dispatching system.

Fig. 1
At KUAS, Dr. Ryo Takahashi will continue to pursue research of the above power packet dispatching system and its application as one of his research targets. This power packet dispatching system has a potential to digitalize power distribution in the same way that communication technology was digitized. This digital power distribution will usher humanity into a new era system design of practical system with power network.