Wind-turbine systems

Wind-turbine systems are being introduced all around the world. At the same time, however, wind -turbine systems are unstable power sources depending on unstable wind, and adverse effects on the electric power system are causing much concern. Research and development on wind-turbine systems that are easy on the power system as well as on the environment are being focused on.

A 1: Since joining Hitachi, I've been involved on research and development on wind-turbine power generation.
Don't you think it surprising that Hitachi is involved in wind turbines? Current wind-turbine systems are controlled to a high degree of accuracy by bundles of high-performance electrical equipment. And Hitachi supplies much of this equipment, such as, control devices, generator sets, and connection equipments to the power system.

In our research group, we are developing power-conditioning system (PCS) for controlling electrical power generated from wind turbines. In recent years, we have been developing 2-MW-class wind-turbine systems in collaboration with Fuji Heavy Industries Ltd.-and these systems have been making headlines. As for these wind-turbine systems, they are fitted with Hitachi's own method called "active and reactive power control" and serve as power-generation systems that are easy on the power system .

A 2: Wind-turbine system-which is viewed with hope as an energy source that produces low carbon-dioxide emission-is our focus; however, is an unstable power source that relies on the wind to generate electricity. When an unstable power sources are connected to a power system largely, adverse effects like fluctuation of the voltage and frequency of the power system occur. Consequently, these effects are obstacle to introduction of wind-turbine systems.

In our group, we are developing technology for connecting such unstable turbine systems to the power grid in a "friendly" fashion. Recently, research on operating systems for combining wind turbines with batteries is steadily progressing. By means of charging and discharging batteries with the fluctuating power generated from wind-turbine systems, that generated power can be stabilized.

An interesting point is that as a result of the charge-discharge control method of the battery, the required battery capacity and the stabilization effect changes greatly. This is talked about as a big moment for control-system design. Moreover, since Hitachi Research Laboratories includes groups performing research and development on batteries, the characteristics of batteries are being discussed frequently. This is a big advantage of gathering researchers from many fields in one integrated research center.

A 3: According to the headlines filling newspapers these days, world opinion is shifting its orientation toward an environmentally conscious society in a big way. I feel that I am, myself, one cog in this mechanism. Accordingly, it is our ultimate goal to become technical experts that go down in history in the environmental field.