Abstract: A wind turbine generator, an active damping method thereof, and a windmill tower in which vibrations of the wind turbine generator itself or the windmill tower can be reduced at low cost are provided. The acceleration is detected with an accelerometer attached to the nacelle. In an active damping unit, a pitch angle of windmill blades for generating a thrust is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command ??* for damping. In a pitch-angle control unit, a pitch angle of the windmill blades for controlling the output, and the pitch angle is output as a blade-pitch-angle command ?* for output control. The blade-pitch-angle command ??* for damping is combined with the blade-pitch-angle command ?* for output control using a subtracter. The pitch angle of the windmill blades is controlled on the basis of the resulting blade-pitch-angle command after combining.

Abstract: An object is to improve the accuracy of reactive power adjustment. Reactive-power command values corresponding to individual wind turbines are determined by correcting a predetermined reactive-power command value for an interconnection node A using reactive power correction levels set for the individual wind turbines.

Abstract: The invention relates to a wind turbine, comprising a tower, a nacelle, at least one blade with a tip end and a root end and monitoring means for monitoring the surface condition of the blade, wherein said monitoring means are located at the tower or at the nacelle and wherein said monitoring means are adapted to monitor the surface condition of at least substantially one entire side of the blade from its tip end to its root end.

Abstract: An object is to improve the accuracy of power factor adjustment. Power-factor command values corresponding to individual wind turbines are determined by correcting a predetermined power-factor command value for an interconnection node using power factor correction levels set for the individual wind turbines.

Abstract: A wind turbine generator, an active damping method thereof, and a windmill tower in which vibrations of the wind turbine generator itself or the windmill tower can be reduced at low cost are provided. The acceleration due to vibrations of a nacelle is detected with an accelerometer attached to the nacelle. In an active damping unit, a pitch angle of windmill blades for generating a thrust on the windmill blades so as to cancel out the vibrations of the nacelle is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command ??* for damping. On the other hand, in a pitch-angle control unit, a pitch angle of the windmill blades for controlling the output to be a predetermined value is calculated, and the pitch angle is output as a blade-pitch-angle command ?* for output control. The blade-pitch-angle command ??* for damping is combined with the blade-pitch-angle command ?* for output control using a subtracter.

Abstract: A method of controlling an operation of a wind power generation system provided with a plurality of wind turbines, in which output power of each wind turbine is supplied to an electric power system through a common interconnection node where output data of each wind turbine is obtained, where a periodic correlation between output fluctuations of adjacent wind turbines is determined by using the output data, the correlation is determined as a strong correlation when the correlation is more than two times greater than an average level of the correlation, and a phase of the output of either one of the adjacent wind turbines is shifted by a period of the strong correlation.

Abstract: A wind turbine generator capable of enhancing starting performance of the wind turbine generator when the outside air temperature is low and capable of securing temperature adjusting ability of a generator set in a wide outside air temperature range is provided. A wind turbine generator includes a nacelle (3) for accommodating a generator set (11, 12, 14) that generates electricity by rotation of a rotor having a plurality of blades, a ventilation opening (51) provided in a wall surface on a wind upstream side when the nacelle is normally operated, and a heat exchanging unit (13) disposed in the ventilation opening (51) to exchange heat between an outside air and a lubricant of the generator set (11, 12) such as an lubricant oil or cooling water.

Abstract: An object is to improve the accuracy of power factor adjustment. Power-factor command values corresponding to individual wind turbines are determined by correcting a predetermined power-factor command value for an interconnection node using power factor correction levels set for the individual wind turbines.

Abstract: A wind turbine generator, an active damping method thereof, and a windmill tower in which vibrations of the wind turbine generator itself or the windmill tower can be reduced at low cost are provided. The acceleration due to vibrations of a nacelle is detected with an accelerometer attached to the nacelle. In an active damping unit, a pitch angle of windmill blades for generating a thrust on the windmill blades so as to cancel out the vibrations of the nacelle is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command ??* for damping. On the other hand, in a pitch-angle control unit, a pitch angle of the windmill blades for controlling the output to be a predetermined value is calculated, and the pitch angle is output as a blade-pitch-angle command ?* for output control. The blade-pitch-angle command ??* for damping is combined with the blade-pitch-angle command ?* for output control using a subtracter.

Abstract: Provided is a wind power generation system intending to suppress an increase of torque when a voltage in a utility grid is restored, and to reduce a load to devices due to the torque. The blade control unit controls the pitch angle of the wind turbine blades such that a rotation speed of the power generator becomes equal to or greater than a synchronous rotation speed when the power control unit de-actuates the operations of the converter and the inverter, and controls the pitch angle of the wind turbine blades such that the pitch angle matches a target pitch angle that is determined based on one of a wind speed, a rotation speed of the power generator, and a requested output power when the power control unit re-actuates the operations of the converter and the inverter.

Abstract: A wind turbine generator, an active damping method thereof, and a windmill tower in which vibrations of the wind turbine generator itself or the windmill tower can be reduced at low cost are provided. The acceleration due to vibrations of a nacelle is detected with an accelerometer attached to the nacelle. In an active damping unit, a pitch angle of windmill blades for generating a thrust on the windmill blades so as to cancel out the vibrations of the nacelle is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command ??* for damping. On the other hand, in a pitch-angle control unit, a pitch angle of the windmill blades for controlling the output to be a predetermined value is calculated, and the pitch angle is output as a blade-pitch-angle command ?* for output control. The blade-pitch-angle command ??* for damping is combined with the blade-pitch-angle command ?* for output control using a subtracter.

Abstract: An apparatus and a method for operating a wind turbine capable of preventing the occurrence of damage of the blades by evading excessive irregular loads from acting on the blades in the slanting direction in the event of power failure when strong wind blows, are provided.

Abstract: A fuel cell stack is divided into a main power generation portion and a sub power generation portion. A variable load large in variation of output current is connected to the main power generation portion located upstream in a fuel flow and a steady load small in variation of output current is connected to the sub power generation portion located downstream in the fuel flow. This causes a fuel cell unit constituting the sub power generation portion to continue consuming a constant fuel by constant power generation and also causes hydrogen gas to continue flowing at a constant flow rate into the fuel cell unit, thereby preventing impurity gas concentrated and stored in the fuel cell unit from diffusing toward the upstream.

Abstract: It is an object to make it possible to completely or partially eliminate a yaw driving device and to reduce power consumption in a nacelle. A moment around a wind-turbine tower axis is calculated; an angle command value around the wind-turbine tower axis is calculated by adding a yaw-control command value to a reference command value for canceling out the moment; and a pitch angle command value of each wind turbine blade is set on the basis of the angle command value around the wind-turbine tower axis.

Abstract: Provided is a wind power generation system intending to suppress an increase of torque when a voltage in a utility grid is restored, and to reduce a load to devices due to the torque. The blade control unit controls the pitch angle of the wind turbine blades such that a rotation speed of the power generator becomes equal to or greater than a synchronous rotation speed when the power control unit de-actuates the operations of the converter and the inverter, and controls the pitch angle of the wind turbine blades such that the pitch angle matches a target pitch angle that is determined based on one of a wind speed, a rotation speed of the power generator, and a requested output power when the power control unit re-actuates the operations of the converter and the inverter.

Abstract: An object is to improve the operating rate. A first switch is provided in a power line connecting a power generator to a power system, and a second switch that can be opened and closed by remote control is provided in the power line between the power generator and the first switch. In the second switch, a withstand current capability is set that allows current flowing in a low-voltage event and that withstands current having a value equal to or less than a current value specified by the thermal setting of the power generator. In the first switch, a withstand current capability is set that is superior to the withstand current capability of the second switch and that withstands current having a value equal to or less than the current value specified by the thermal setting of the power generator.

Abstract: Disclosed is a polyol composition containing an aromatic polyester polyol having a hydroxyl number of 300-500 mgKOH/g and an average number of functional groups of 2.0-2.5, a medium-chain polyether polyol having a hydroxyl number of 100-250 mgKOH/g and an average number of functional groups of 2.0-4.0 and composed of a polyoxypropylene unit, and a long-chain polyether polyol having a hydroxyl number of 15-40 mgKOH/g, an average number of functional groups of 2.0-4.0 and an oxyethylene content of not more than 14% by weight and mainly composed of a polyoxypropylene unit.

Abstract: An electrochromic element includes a pair of transparent electrodes, and an electrolyte layer and an electrochromic layer disposed between the pair of transparent electrodes. Transmittance of light is changed by a voltage applied to the pair of transparent electrodes. The electrochromic layer includes a first electrochromic layer and a second electrochromic layer stacked upon each other. Both of the first and second electrochromic layers are made of titanium oxide. The first electrochromic layer is in contact with one of the pair of transparent electrodes. The second electrochromic layer is in contact with an electrolyte-layer side of the first electrochromic layer. A refractive index n0 of the transparent electrode in contact with the first electrochromic layer, a refractive index n1 of the first electrochromic layer, and a refractive index n2 of the second electrochromic layer satisfy the relationship n0<n1<n2.

Abstract: Provided are a wind turbine generator and a method for constructing a wind turbine generator that allow for alleviation of construction costs, particularly for large wind turbine generators, and alleviation of limitations on construction due to weather. Provided are a rotor head that has a plurality of wind turbine rotor blades and that is rotated by wind power received by the plurality of wind turbine rotor blades, a front segment disposed on top of a tower and constituting a nacelle to which the rotor head is attached, a rear segment attached to the front segment and constituting the nacelle, a front frame disposed in the front segment and positioned between the rotor head and the tower so as to support a load on the rotor head, a rear frame disposed in the rear segment and attached to the front frame, a front cover covering the periphery of the front segment, and a rear cover covering the periphery of the rear segment.

Abstract: The present invention proposes a lightning protection device of a windmill blade, comprising a tip receptor assembly having receptors which are mounted, in particular to, the tip end part of the blade where the blade profile becomes smaller, and having a simple structure so as to be readily assembled, and an intermediate receptor assembly having a receptor which is set at the outer surface of the blade so as to exhibit an effective countermeasure against increasing of the air pressure in the blade upon a lightning striking upon the blade, a lightening current being discharged to the ground from the receptors through connection equipment such as lead wires laid through the inside of the blade the windmill body and bypass brushes, characterized in that a base plate made of an electrically conductive material and connected thereto with the lead wires is embedded in the blade, and the receptors are secured and supported to the base plate, being exposed at the outer surface of the blade.