Abstract: A water or wind turbine in which fatigue fracture is less likely to be generated in a rotation shaft is provided. A wind turbine comprises: a rotation shaft extending in the vertical direction; a plurality of arms extending horizontally from the rotation shaft and formed at equal intervals along the rotation direction; and a plurality of wings attached to tips of the arms and extending in the upper/lower direction, and the rotation shaft is rotated by lift generated on the wings, wherein cross sections of the wings have a uniform shape and a uniform area from upper ends of the wings to lower ends of the wings, wherein seen from the extending direction of the rotation shaft, the plurality of wings are projected on the entire circumference of a single virtual circular ring C whose center is on the rotation shaft, and wherein lengths of the wings in the vertical direction are equal over the entire circumference.

Abstract: A management or control of a power router is more appropriately performed when a power network system in which power cells are asynchronously connected with each other. A plurality of power conversion legs bi-directionally convert power, one ends thereof are connected with a direct current bus and the other ends thereof are connected with an external connection destination as an external connection terminal. A control unit controls operations of the plurality of power conversion legs. The control unit receives a control instruction including a designation of an activation target leg and a designation of an operation mode of the activation target leg. The control unit determines whether the activation target leg can be activated in a designated operation mode. The control unit activates the activation target leg in the designated operation mode when the activation target leg can be activated in the designated operation mode.

Abstract: Provided is a power router to construct a power network system in which power cells are asynchronously interconnected. The power router includes a DC bus, a power conversion leg having a function of bidirectionally converting power, and a controller that controls an operation of the power conversion leg. The power conversion leg operated in a master mode supplements (or sends) an insufficient (or excessive) power from (or to) a connection partner, when a voltage of the DC bus decreases (or increases) from a rated voltage. The power conversion leg operated in a designated power transmission/reception mode sends a designated power to the connection partner or receives the designated power from the connection partner according to a designation from a management server. The controller sets the mode of at least one of the power conversion legs to the master mode during the operation of the power router.

Abstract: The present invention provides a multi-terminal power conversion device, a multi-terminal power transfer device, and a power network system which allows an existing power grid to be divided into a plurality of power grids that can be interconnected together and operated stably via existing or new transmission lines. An inter-power grid asynchronous interconnection network system includes a multi-terminal power conversion device characterized by connecting together a plurality of asynchronous power grids including a bulk power grid and controlling power so that the sum of inflow power and outflow power is zero. An intra-power grid synchronous network system includes a power apparatus control terminal device with means for controlling power for a power apparatus installed in an autonomous power grid. A plurality of inter-power grid asynchronous interconnection network systems are connected to an intra-power grid synchronous network system to integrate the power control with communication control.

Abstract: The present invention provides a multi-terminal power conversion device, a multi-terminal power transfer device, and a power network system which allows an existing power grid to be divided into a plurality of power grids that can be interconnected together and operated stably via existing or new transmission lines. An inter-power grid asynchronous interconnection network system includes a multi-terminal power conversion device characterized by connecting together a plurality of asynchronous power grids including a bulk power grid and controlling power so that the sum of inflow power and outflow power is zero. An intra-power grid synchronous network system includes a power apparatus control terminal device with means for controlling power for a power apparatus installed in an autonomous power grid. A plurality of inter-power grid asynchronous interconnection network systems are connected to an intra-power grid synchronous network system to integrate the power control with communication control.