Abstract:
The invention concerns a direct drive or directly driven generator for a wind turbine comprising a stator and a rotor, wherein the stator comprises a stator ring comprising several ring-segment-shaped stator segments each having at least one stator element for the power generation and wherein the rotor comprises a rotor ring pivotable around a centre axis of the generator, the rotor ring comprises several ring-segment-shaped rotor segments each having at least one rotor element for the power generation. Furthermore the invention concerns a wind turbine comprising such a direct drive generator.
Abstract:
A method for making a windmill blade is provided, whereby problems with glue joints and with exposure of the workers to environmentally hazardous substances are avoided. This is effected by making the windmill blade in a closed mold with a mold core (3) inside mold parts (22, 48) for formation of a mold cavity (51), in which fiber material (45, 47) and core material (46) are placed. After applying vacuum to the mold cavity (51), matrix material (57) is injected via a filling pipe (29), which is placed at a downwardly oriented side edge of the blade during the filling. Hereby is established a flow front (61) which is used for indicating complete filling when this reaches the trailing edge of the blade and penetrates out through overflow apertures.
Abstract:
The present invention provides a power converter that can be used to interface a generator that provides variable voltage at variable frequency to a supply network operating at nominally fixed voltage and nominally fixed frequency and including features that allow the power converter to remain connected to the supply network and retain control during supply network fault and transient conditions. The power converter includes a generator bridge electrically connected to the stator of the generator and a network bridge. A dc link is connected between the generator bridge and the network bridge. A filter having network terminals is connected between the network bridge and the supply network. A first controller is provided for controlling the operation of the semiconductor power switching devices of the generator bridge. Similarly, a second controller is provided for controlling the operation of the semiconductor power switching devices of the network bridge. The first controller uses a dc link voltage demand signal VDC_NET* indicative of a desired dc link voltage to control the semiconductor power switching devices of the network bridge to achieve the desired level of dc link voltage that corresponds to the dc link voltage demand signal VDC_NET*. The second controller uses a power demand signal P* indicative of the level of power to be transferred from the dc link to the supply network through the network bridge, and a voltage demand signal VTURB* indicative of the voltage to be achieved at the network terminals of the filter to control the semiconductor power switching devices of the network bridge to achieve the desired levels of power and voltage that correspond to the power and voltage demand signals P* and VTURB*.
Abstract:
The invention concerns a generator for a windmill. The generator is of the kind being directly coupled to the main shaft of the wind rotor of the windmill. The generator is a stator consisting of a number of stator modules that are individual and which may be installed, repaired and dismantled individually and independently of each other. This implies that it is very easy and thereby cheaper to mount the mill, especially at sea, as the stator for the generator can be transported in smaller units, which also makes it easier to assemble the stator in the tower top section. By sequent repairs and other maintenance of the generator it is not necessary either to use large cranes, but it is sufficient to use smaller hoisting devices that may be handled by one or two persons.
Abstract:
The application relates to a floatable foundation structure for an offshore structure including at least one floating body arrangement and at least one mass arrangement. The mass arrangement is connected to the floating body arrangement by at least one holding rope in a coupling state. Further, in the coupling state for coupling the floating body arrangement to the mass arrangement, a coupling section of the holding rope is arcuately guided around a contact section of the mass arrangement.
Abstract:
An arrangement and a method of rotating a hub of a wind turbine are provided. A wind turbine includes a hub mounted to a nacelle, whereby the hub is rotatable around an axis of rotation in respect to the nacelle. A rotor blade is arranged at the hub that leads to a torque around the axis of rotation of the hub. A counter weight is attached to the hub, whereby the counter weight has a mass that leads to a counter-torque around the axis of rotation. The counter-torque interacts with the torque during the installation of a second rotor blade to the hub. The counter weight is mounted to the hub by a mechanical arrangement that is rotatable in respect to the hub around the axis of rotation of the hub. The mechanical arrangement and the counter weight are rotatable in respect to the hub into a certain predetermined position.
Abstract:
A thermal energy storage and recovery device is provided including a container having a first fluid terminal for inserting heat transfer medium into the interior of the container and a second fluid terminal for extracting heat transfer medium from the interior of the container, a heat storage material for receiving thermal energy from the heat transfer medium when in a first operational mode and releasing thermal energy to the heat transfer medium when in a second operational mode, and a plurality of enclosures each filled at least partially with a part of the heat storage material. The enclosures are spatially arranged within the container so a flow of the heat transfer medium is guidable between the first and second fluid terminals and a direct thermal contact between the heat transfer medium and the enclosures is achievable as the heat transfer medium flows between the first and second fluid terminals.
Abstract:
A wind turbine blade is disclosed. The blade includes a heating mat for generating heat. The heating mat is mounted at an outer surface of the blade. The heating mat includes a first section with a first end section and a second section with a second end section. The first end section and the second end section are electrically connectable to a respective power terminal for supplying power to the heating mat. The second end section defines an opposite end section of the heating mat in a longitudinal direction of the heating mat with respect to the first end section. The first section and the second section run along the surface of the blade in one or more loops from the first end section to the second end section.
Abstract:
A stator system for a generator, in particular a generator of a wind turbine is disclosed. The stator system includes a housing element including a groove and a cap element for closing the groove such that a channel for guiding a cooling fluid within the groove is formed. The cap element includes a magnetic material.
Abstract:
A method is provided for the production of tower segments, which are used to assemble a wind turbine tower. The method includes providing a sheet steel, cutting the sheet steel into a plurality of steel plates, cutting at least one opening in the plurality of steel plates, and bending the steel plates into a desired shape. The steps are performed in a continuous process, such that the steel plates move from one step in the production to the next.