小水力発電への可変速システムの適用

抄録

The Dashidaira Power Station utilizes water discharged from its dam in such a way that a good environment is maintained for the river on which it is located. However, the large variations in the head and flow rate of the water would impede stable operation under certain operating conditions in the case of a conventional hydraulic turbine with a fixed rotation speed. To resolve this issue, we developed an adjustable-speed system for small-scale hydroelectric power plants and delivered it to Dashidaira Power Station. This system makes stable operation possible over the full range of operations by allowing the rotation speed of the hydraulic turbine to be adjusted over a wide range through the connection of a frequency converter to the output terminal of the generator. As a result, the power station efficiently utilizes water resources that have not been effectively used up to now.