Patents Assigned to REpower System AG
  • Publication number: 20100176770
    Abstract: An electricity generating installation is connected to an electricity distribution network and feeds electrical power into the network via a converter. After detecting a network fault, a stabilization regulator in the installation is activated. The stabilization regulator regulates the voltage of the electrical power as a function of a fed-back voltage signal and has a step-function response that rises over time. After a predetermined time period has elapsed since the activation of the stabilization regulator, the reactive current feed is increased beyond a limit which is provided for normal operation if the network has not stabilized. Accordingly, a converter-fed electricity generating installation, such as a wind energy installation, can help stabilize an electricity distribution network after a network fault.
    Type: Application
    Filed: December 9, 2009
    Publication date: July 15, 2010
    Applicant: REpower Systems AG
    Inventor: Jens Fortmann
  • Publication number: 20100179773
    Abstract: A method and system for monitoring the operation of a wind energy installation. State data relating to the wind energy installation is recorded and discrepancies are found between the state data and an associated comparison value. A failure probability of the wind energy installation is determined based on any found discrepancy. An availability value for the wind energy installation is determined from the ratio of the actually produced amount of electrical energy to the total amount of energy which can potentially be produced. The availability value and the failure probability are then combined to form a repair priority, which is associated with the wind energy installation. Accordingly, more uniform operation of wind energy installations can be achieved.
    Type: Application
    Filed: January 12, 2010
    Publication date: July 15, 2010
    Applicant: REpower System AG
    Inventor: Jens Altemark
  • Publication number: 20100148506
    Abstract: A wind turbine includes a rotor having adjustable rotor blades for driving a generator and an adjusting device for the rotor blades provided with an actuator that comprises at least an excitation winding. The adjusting device includes a torque-reducing device that automatically reduces drag torque of the actuator. The torque-reducing device includes a current divider that switches the current through the excitation winding in such a manner that the current flows completely through the excitation coil when the motor is in operation and the current only partly flows through the excitation coil when coasting (slip operation). As a result, when coasting, the magnetization of the excitation winding is reduced about the adjusting device, whereby the increase of the speed torque characteristic curve can be determined, thus improving the ratio of the adjusting device when coasting.
    Type: Application
    Filed: May 14, 2008
    Publication date: June 17, 2010
    Applicant: REpower Systems AG
    Inventor: Heinz-Hermann Letas
  • Publication number: 20100091417
    Abstract: An overvoltage protective device for wind energy installations is designed for connection to a connecting line having at least one inductance between a wind energy installation and a grid system. The overvoltage protective device has a controller which operates a limiting unit as a function of an overvoltage at the wind energy installation. The limiting unit comprises a spur line having an induction module and a power tapping module which is provided with a switching unit. This yields a second power strand which can accept a considerable reactive current if necessary, thus increasing the voltage drop across the inductance, as a result of which the voltage acting on the wind energy installation is reduced.
    Type: Application
    Filed: September 29, 2009
    Publication date: April 15, 2010
    Applicant: REpower Systems AG
    Inventor: Heinz-Hermann LETAS
  • Publication number: 20100052322
    Abstract: A wind energy installation can include a generator which is driven by a rotor and generates electrical power in a multiphase manner for feeding into a network, a converter which is connected to the generator and to the network, and a control system which interacts with the converter and includes a negative sequence system regulation mechanism. The negative sequence system regulation mechanism can include a phase control module configured to determine an electrical variable of the negative sequence system according to the phase. Accordingly, an available current can be provided according to the operating situation for active power or idle power in the negative sequence system regulation mechanism. The negative sequence system regulation mechanism can thus help stabilize the network in the event of asymmetrical network conditions. Also, this relates to a correspondingly equipped wind park and an operating method.
    Type: Application
    Filed: November 20, 2007
    Publication date: March 4, 2010
    Applicant: REpower Systems AG
    Inventors: Jens Fortmann, Heinz-Hermann Letas
  • Publication number: 20100001527
    Abstract: A system for a wind energy installation. The wind energy installation feeds electrical power into a power supply system. A phase control device can include a power supply system fault detector, a phase angle detector, and a signal processing module. When a power supply system fault is detected, a phase error signal can be determined. A preset angle signal can be determined based on the phase error signal. The preset angle signal can be provided to a converter which can emit electrical power having a phase angle corresponding to the preset angle signal into the power supply system. Accordingly, an undesirable sudden surge in power output resulting from a phase change occurring at the end of the power supply system disturbance can be avoided.
    Type: Application
    Filed: October 17, 2007
    Publication date: January 7, 2010
    Applicant: REpower Systems AG
    Inventors: Jens Fortmann, Heinz-Hermann Letas
  • Publication number: 20090322086
    Abstract: A converter for a wind energy installation and a method. The converter includes an inverter which drives a generator via a plurality of phases and an intermediate circuit having an intermediate-circuit voltage between an upper and a lower intermediate-circuit potential. The generator is driven with phase potentials at a variable frequency. A shift value is calculated between an extreme phase potential and one of the intermediate-circuit potentials, a separation value is determined between a middle phase potential and the closest intermediate-circuit potential, and an additional voltage is generated using the separation value as amplitude. The phase potentials are shifted through the shift value and the additional voltage is added to the middle phase potential. Accordingly, the switching elements in the converter do not need to be clocked in every second half-cycle resulting in reduced switching losses and increased current load capacity of the converter.
    Type: Application
    Filed: June 19, 2009
    Publication date: December 31, 2009
    Applicant: REpower Systems AG
    Inventor: Heinz-Hermann LETAS
  • Publication number: 20090289804
    Abstract: An offshore wind farm can include at least two wind energy installations for generating electrical power from wind, at least two acoustic warning devices, and a visibility measuring device for detecting visibility. After detection of a visibility below a visibility limit value, an activation signal can be applied to the at least two acoustic warning devices. One or more synchronization modules can be provided which determine the points in time of the acoustic signals to be emitted by at least one of the acoustic warning devices in relation to the acoustic signals of the other acoustic warning devices. Accordingly, this facilitates the navigation along an offshore wind farm and enables safe circumnavigation. Also, the impression of a contiguous area can be conveyed to the ships by the synchronized emission of the warning signals.
    Type: Application
    Filed: May 20, 2009
    Publication date: November 26, 2009
    Applicant: REpower Systems AG
    Inventors: Lorenz-Heinrich CARSTENSEN, Jens ALTEMARK
  • Publication number: 20090261588
    Abstract: A method for operating a wind energy installation and a system for implementing the method. An oblique incident flow value, which represents the difference between the wind direction and the direction of a rotor axis of the wind energy installation, and a load value, which represents the load state of the wind energy installation, are determined. A total load value is determined based on the load value and the oblique incident flow value. The rotor rotation speed is reduced when the total load value is above a first limit value. The wind energy installation is shut down when, in addition, a second limit value is exceeded. The method makes it possible to react objectively to oblique incident flows and can reduce a load on a wind energy installation without causing large yield losses.
    Type: Application
    Filed: April 22, 2009
    Publication date: October 22, 2009
    Applicant: REpower Systems AG
    Inventors: Martin VON MUTIUS, Roland WEITKAMP, Jochen ANEMUELLER
  • Patent number: 7606638
    Abstract: A windpark includes at least two wind energy installations, each of which installations comprises a rotor, a generator driven by the rotor and a control device, and which are connected via connecting lines to a main line. The windpark also includes a linking point which connects the main line to a power transmission network, a parkmaster which is configured for power factor control and has communication lines for transmission of control signals to the wind energy installations, and a power-factor control section including a distributed regulator having a higher-level regulator located at the parkmaster which is configured to determine a nominal voltage in order to set a global power coefficient for the power which is emitted to the power transmission network and to emit the nominal voltage as a signal via the communication lines and lower-level regulators at the wind energy installations.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: October 20, 2009
    Assignee: REpower Systems AG
    Inventors: Jens Fortmann, Heinz-Hermann Letas
  • Patent number: 7603202
    Abstract: A method for optimizing the operation of wind energy installations includes operating target and reference wind energy installations to optimize the target installation first using a first set of operating parameters and then using a second set of operating parameters different from the first operating parameters, recording target variables for the target wind energy installation and recording reference results of the reference wind energy installation in each case for both sets of operating parameters, performing an automated evaluation of the target variables by calculation of a quality measure taking account of the reference results, and determining in an automated manner based on the automated evaluation which of the sets of operating parameters has better quality measure. Each wind installation includes comprise a rotor, a generator driven by the rotor to produce electrical energy, and a controller operating the wind energy installation on the basis of a set of operating parameters.
    Type: Grant
    Filed: November 22, 2005
    Date of Patent: October 13, 2009
    Assignee: REpower Systems AG
    Inventor: Roland Weitkamp
  • Publication number: 20090243296
    Abstract: Wind energy installation with a generator (13) which is driven by a rotor (2) with adjustable rotor blades (21), for producing electrical energy, wherein a pitch adjustment device (3) is provided for adjusting the blades, which pitch adjustment device comprises an emergency circuit (5) with an energy store (50) for actuating a blade actuating motor (55). The invention provides for a shunt branch (60) with a current-balancing device (6, 6?) to be provided in parallel with the energy store (50), wherein the current-balancing device (6, 6?) is designed so as to control the current shunt branch (60) depending on a feedback current from the blade actuating motor (55). The invention provides a current balancing circuit (6), with which the feedback current occurring in the overrunning state is dissipated in controlled fashion via a shunt branch and therefore the electrical energy store (50) is protected from a damaging feedback current.
    Type: Application
    Filed: June 12, 2007
    Publication date: October 1, 2009
    Applicant: REpower Systems AG
    Inventor: Heinz-Hermann Letas
  • Publication number: 20090210200
    Abstract: A method for providing operating data of a wind farm comprising a plurality of wind farm components. The operating data of the wind farm components are recorded and are stored in the relevant wind farm component. The operating data are sent to a plurality of receivers using a push method. The method simplifies the management of the operating data and requires only minimal transmission capacity in the data line of the wind farm component.
    Type: Application
    Filed: February 13, 2009
    Publication date: August 20, 2009
    Applicant: REpower Systems AG
    Inventors: Guntram KUNFT, Ralf ELSNER, Markus BOOK, Matthias PRINZ
  • Patent number: 7571013
    Abstract: A method for optimization of operating parameters of a wind energy installation defines an upper and a lower interval limit value for a parameter to be optimized. The method includes carrying out a cycle with alternate operations of the wind energy installation with the interval limit values, with a data record in each case being produced with a target variable over a variable number of repetitions. The data records relating to the interval limit values are evaluated to form a quality measure, and the interval limit value with the poorer quality measure is identified. Then, at least the interval limit value with the poorer quality measure is replaced by shifting through a step value ? in a direction of another interval limit value. The cycle is then repeated.
    Type: Grant
    Filed: November 22, 2005
    Date of Patent: August 4, 2009
    Assignee: REpower Systems AG
    Inventor: Jens Altemark
  • Patent number: 7550862
    Abstract: The invention relates to a wind turbine comprising a machine housing (12) equipped with a rotor (14), which is mounted to pivot on a sub-structure (10). Wind parameters and an electromechanical quantity are determined by means of measuring devices (21, 22, 23). To enable the machine housing (12) to track the wind, the wind turbine is equipped with a pivoting device (11) comprising a controller (8). The wind turbine is also equipped with a calibration module (2), which is configured to determine an effective mass of the electromechanical quantity using the wind speed. In addition, the turbine comprises an evaluation device (4) comprising a classifier (40), which is used to form a first average value for a first class, for which the wind direction is positive and a second average value for a second class, for which the wind direction is negative. A difference is determined by means of a comparator and a calibration signal is emitted to the controller (8) of the pivoting device (11).
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: June 23, 2009
    Assignee: REpower Systems AG
    Inventor: Jens Altemark
  • Patent number: 7528496
    Abstract: A method for operating at least one wind turbine with a rotor and an electric generator coupled to the rotor for delivering electrical power into an energy distribution system with the aid of a control device ensures that the wind turbine operates within its operating range. The wind turbine is controlled in response to the change of a system operating parameter and for a period of time, in such a manner that a higher power is fed into the system than belongs to the operating range of the steady-state operation. The same conditions also apply to a method for providing control power or primary control power for an electric energy generator and distributor system to which a multiplicity of power stations including wind turbines is connected, and to a wind turbine.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: May 5, 2009
    Assignee: REpower Systems AG
    Inventor: Jens Fortmann
  • Publication number: 20090102196
    Abstract: A method and a system are for determining of the compatibility of control software, which is designed for standard parameters, with a wind energy installation which is operated using operating parameters. The method is an automatic method in which the operating parameters of the wind energy installation and the standard parameters of the control software are first transmitted to a computation unit. The computation unit determines discrepancies between the operating parameters and the standard parameters. A decision on compatibility is made on the basis of the discrepancies. The system includes a logic module which is designed to make the decision. This method makes it easier to automatically update the control software for a wind energy installation. There is no longer any need to manually check the compatibility of the new version of the control software before the new version of the control software can be installed.
    Type: Application
    Filed: September 22, 2008
    Publication date: April 23, 2009
    Applicant: REpower Systems AG
    Inventors: Jens ALTEMARK, Markus BOCK, Anton KUPPER
  • Publication number: 20090021014
    Abstract: A wind energy installation includes a wind rotor, a double-fed asynchronous generator driven by the wind rotor, a converter provided with a first part on the generator side connected to a rotor and a second part on the network side connected to a stator of the generator, and a control device providing converter regulation. A mode selector can be switched between a normal operating mode and a reduced voltage operating mode, in which the excitation of the generator is reduced compared to the normal operating mode. The under-excitation produces an additional reactive current, thus reducing the rotor voltage. The rotor voltage can be limited even when the load is high and the network frequency or voltage is incorrect. The usable rotation speed range of the wind energy installation can be extended to provide a more powerful generator with a higher rating, without changing the converter.
    Type: Application
    Filed: July 10, 2008
    Publication date: January 22, 2009
    Applicant: REpower Systems AG
    Inventor: Heinz-Hermann LETAS
  • Publication number: 20090001726
    Abstract: A wind energy installation includes a tower provided with rotor blades that are adjusted using a servomotor connected to a pitch circuit and an emergency circuit. During normal operation the rotor blades are actuated by the pitch circuit and during emergency operation are actuated by the emergency circuit. The emergency circuit has an electric energy store, a switching device, connection lines to the servomotor and a protection device which includes comprises a power flow detector module (60) designed for determining whether electric power flows into or from the servomotor and a discharge module designed to limit the voltage and/or current in the emergency circuit in the case of a power flow from the servomotor.
    Type: Application
    Filed: February 23, 2007
    Publication date: January 1, 2009
    Applicant: REpower Systems AG
    Inventors: Karsten Warfen, Heinz-Hermann Letas
  • Publication number: 20080290664
    Abstract: Provided herein is a wind energy installation including a generator for production of electrical energy, a rotor which drives the generator and has variable pitch rotor blades and a central control device, and individual pitch devices provided individually for the rotor blades. The individual pitch devices may include an adjustment drive, a communication link to the central control device and a regulator, the rotor blades being adjustable in order to slow down the wind energy installation to a shut-down position. The individual pitch devices may also include a disturbance situation detector which is designed to identify abnormal operating states and to move the rotor blades to a shut-down position. Also provided herein is the method of operating such a wind energy installation.
    Type: Application
    Filed: July 26, 2006
    Publication date: November 27, 2008
    Applicant: REpower Systems AG
    Inventor: Thomas Kruger