1.Optimum Operation of Electric Power System Considering Renewable Energy
In this research, we develop a new power system operation method different from the conventional one with the purpose of achieving both maximum utilization of renewable energy (RE) power supply and stable power supply to customers. Specifically, the power outputs from many RE systems in power systems are synthesized, and after that, it is divided into long-term components and short-cycle components. For the long-term component, balancing operation between supply and demand is planned while taking into account of operation of system battery, pumped-storage power generation, power interchange. On the other hand, for the short-term component, we develop a method for utilizing as spinning reserves many local resources such as air conditioners and electric vehicles (EV) owned by customers, household storage batteries, cogeneration systems, etc.
2. New Operation and Control in Distribution System
In this research, in order to deal with voltage change and/or voltage violation in distribution system under the mass introduction of PV system, we develop a method to estimate the voltage distribution of the distribution system using information from smart meters and sectionalized switches with communication function. Further, we develop a method to perform advanced voltage control in distribution system while considering changes in system topology. Also, since rapid charger for EV can inject and absorb reactive power in principle by using the inverter in the charger, we develop voltage control method of distribution system utilizing reactive power compensation of charger.
3. Research on Power to Heat and Power to Gas
In recent years, attention has been focused on a technology for converting renewable energy power to heat (Power to Heat, P2H) or hydrogen (Power to Gas, P2G) as one measure for introducing a large amount of renewable energy power supply. In this research, for P2H, we develop a biogas electric and heat energy system combined with a heat pump, and develop a new method to make it operate as an equivalent storage battery.
On the other hand, with regard to P2G, to realize a smart community that converts surplus electric power of PV to hydrogen, a micro grid including hydrogen production process as an electric demand is assumed. It is also intended to clarify the features of FCV as seen from the viewpoint of power system operation, assuming a fuel cell vehicle (FCV) using hydrogen as a fuel.
4. Study on off-grid distribution system
In this research, in order to make use of renewable energy power supply as the main power source in the off-grid distribution system, we develop an operation method that balances the supply and demand in the off grid while also using the free capacity of the storage battery. We also examine the operation and control of off-grid distribution system considering maintenance of voltage utilizing reactive power of storage battery.
