Patents by Inventor Poul Brandt Christensen
Poul Brandt Christensen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20190078555Abstract: There is provided a method for controlling a hydraulic pitch force system (220) so as to reduce or eliminate a decrease in hydraulic oil pressure (241) if a hydraulic system parameter value is outside a hydraulic system parameter range, the method comprising: Obtaining (690) the hydraulic system parameter value, and operating the hydraulic pitch force system (220) according to a reduced mode (692) if the hydraulic system parameter value is outside the hydraulic system parameter range, wherein in the reduced mode one or more pitch based activities are reduced (694) or suspended. An advantage thereof may be that it enables keeping the wind turbine in production in certain instances rather than shutting down the wind turbine. In aspects, there is furthermore presented a computer program product, a pitch control system (250) and a wind turbine (100).Type: ApplicationFiled: October 11, 2016Publication date: March 14, 2019Applicants: Vestas Wind Systems A/S, Vestas Wind Systems A/SInventors: Martin Ansbjerg Kjær, Frank Møller Hansen, Jacob Hviid Nielsen, Jesper Lykkegaard Neubauer, Poul Brandt Christensen, Fabio Caponetti, Christian Skallebæk, Robert Grøn-Stevens, Kasper Zinck Østergaard
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Publication number: 20190055923Abstract: A method for damping an oscillation of a tower of a wind turbine is disclosed, wherein a pitch angle of each of the one or more rotor blades is individually adjustable, the method comprising damping the oscillation of the tower by pitching each rotor blade individually according to tower damping pitch control signals, wherein each tower damping pitch control signal comprises a first periodic component, where a first frequency of the first periodic component corresponds to a frequency difference between a tower frequency of the oscillation of the tower and a rotor frequency of a rotation of the rotor, and where a second periodic component has been reduced or removed. A second frequency of the second periodic component corresponds to a frequency sum of the tower frequency and the rotor frequency.Type: ApplicationFiled: February 24, 2017Publication date: February 21, 2019Inventors: Fabio CAPONETTI, Jesper Sandberg THOMSEN, Jacob Deleuran GRUNNET, Poul Brandt CHRISTENSEN
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Patent number: 9957951Abstract: A method of controlling a wind turbine having a rotor and a generator for producing power, the wind turbine being designed for a nominal load, the method comprising the steps of: determining a current load acting on at least a part of the wind turbine; calculating a load error, the load error representing the difference between the nominal load and the current load; controlling the wind turbine based on the load error; wherein the step of controlling the wind turbine comprises altering a parameter of the wind turbine so that the power or torque produced by the generator is altered.Type: GrantFiled: February 17, 2016Date of Patent: May 1, 2018Assignee: Vestas Wind Systems A/SInventor: Poul Brandt Christensen
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Publication number: 20170184077Abstract: The invention relates to a method for determining dynamic parameters associated with damping properties of a wind turbine. The method involves active excitation of tower oscillations by adjusting the pitch or rotor torque. After the active excitation, the parameters can be determined from the passive decay of the excited oscillations. Alternatively, the oscillations can be actively damped, so that the parameters can be determined from the active decay of the excited oscillations. The method for promoting oscillations may be triggered in response to different events or in response to predetermined times for determining the actual dynamic parameters.Type: ApplicationFiled: June 5, 2015Publication date: June 29, 2017Applicant: Vestas Wind Systems A/SInventors: Fabio CAPONETTI, Ian COUCHMAN, Jacob Deleuran GRUNNET, Ilias Konstantinos ARISTON, Poul Brandt CHRISTENSEN
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Publication number: 20160252075Abstract: Methods and systems for controlling a wind turbine in a manner that takes into account the degree of loading of and damage to one or more components of the turbine are provided. An operational load on a wind turbine part is determined, and is used to compute a damage signal. The damage signal is indicative of the potential damage to the component or to the turbine as a whole that will result if action is not taken to reduce or mitigate the determined load. When the damage signal exceeds a pre-determined threshold, load-reducing wind turbine control means are activated to obviate the estimated damage.Type: ApplicationFiled: October 6, 2014Publication date: September 1, 2016Inventors: Thomas KRÜGER, Martin ATZLER, Poul Brandt CHRISTENSEN, Robert BOWYER
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Publication number: 20160208781Abstract: To efficiently nm a wind turbine in varying wind speeds, the wind turbine may be configured to switch between two different electrical configurations that offer different efficiencies depending on wind speed. For example, a star configuration may be preferred during low wind speeds while a delta configuration is preferred for high wind speeds. Before switching, the power output by the turbine's generator may be driven to zero. Doing so, however, removes load from the rotor blades which cause the rotor speed to increase. Instead, the rotor speed may be controlled such that the speed stays at or above the speed of the rotor immediately before the generator power is ramped down. Maintaining rotor speed at or slightly above the current speed while switching between electrical configurations may mitigate the torque change experienced by the turbine and reduce the likelihood of structural failure.Type: ApplicationFiled: September 3, 2014Publication date: July 21, 2016Inventors: Martin Ansbjerg KJÆR, Peter KOLDKJÆR, Mølgaard Hviid KNUDSEN, Maryam SOLEIMANZADEH, Martin Møller SØRENSEN, Ali ZAIB, Arvishwa Kumar SINGH, Poul Brandt CHRISTENSEN, Michael Houlind JENSEN
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Publication number: 20160169200Abstract: A method of controlling a wind turbine having a rotor and a generator for producing power, the wind turbine being designed for a nominal load, the method comprising the steps of: determining a current load acting on at least a part of the wind turbine; calculating a load error, the load error representing the difference between the nominal load and the current load; controlling the wind turbine based on the load error; wherein the step of controlling the wind turbine comprises altering a parameter of the wind turbine so that the power or torque produced by the generator is altered.Type: ApplicationFiled: February 17, 2016Publication date: June 16, 2016Inventor: Poul Brandt Christensen
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Publication number: 20150369214Abstract: The invention relates to a controller configured to determine one or more future values of blade control references and/or a generator control references for a wind turbine generator. The first of the future values of the control references are used for control purposes. The future control references are determined from a physical model of a system of the wind turbine generator by solving an optimization problem which includes at least one cost function and at least one constraint.Type: ApplicationFiled: February 4, 2014Publication date: December 24, 2015Inventors: Eik HERBSLEB, Fabiano DAHER ADEGAS, Poul Brandt CHRISTENSEN, Robert BOWYER, Fabio CAPONETTI, Ian COUCHMAN, Lars Finn SLOTH LARSEN
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Patent number: 7964979Abstract: A method of controlling a wind turbine, where a control signal for a controllable parameter of the wind turbine is determined, and the rotor power coefficient, the torque coefficient, and/or a thrust coefficient of the wind turbine are estimated at time intervals. From this is determined a variation parameter reflecting the variation of the estimated rotor power, torque or thrust coefficient over time. The wind turbine is then controlled according to the control signal only if the variation parameter is below an alert threshold, and otherwise according to a modified control strategy. The control signal may have a power or torque reference signal for controlling the rotational speed of the turbine or a blade pitch reference signal. The modified control method may for instance entail stopping or de-rating the wind turbine. A control system configured to perform the above control method, and a wind turbine comprising such system are also disclosed.Type: GrantFiled: October 1, 2010Date of Patent: June 21, 2011Assignee: Vestas Wind Systmes A/SInventors: Erik Carl Lehnskov Miranda, Imad Abdallah, Poul Brandt Christensen, Ali Zaib, Thomas Tvilum Bachmann
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Patent number: 7942634Abstract: A wind turbine includes a rotor having one or more rotor blades, a pitch system for controlling the pitch angle of the one or more rotor blades, the pitch system having at least one pitch actuator, a pitch controller for generating pitch actuator control signals and sensor elements for establishing values of pitch performance parameters, and a compensation controller to compensate for disparities between the pitch actuator control signals and the values of pitch performance parameters, according to a control algorithm. The compensation controller is arranged to adjust parameters of the control algorithm of the compensation controller in dependency of the disparities.Type: GrantFiled: January 14, 2010Date of Patent: May 17, 2011Assignee: Vestas Wind Systems A/SInventor: Poul Brandt Christensen
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Publication number: 20110084485Abstract: A method of controlling a wind turbine, where a control signal for a controllable parameter of the wind turbine is determined, and the rotor power coefficient, the torque coefficient, and/or a thrust coefficient of the wind turbine are estimated at time intervals. From this is determined a variation parameter reflecting the variation of the estimated rotor power, torque or thrust coefficient over time. The wind turbine is then controlled according to the control signal only if the variation parameter is below an alert threshold, and otherwise according to a modified control strategy. The control signal may have a power or torque reference signal for controlling the rotational speed of the turbine or a blade pitch reference signal. The modified control method may for instance entail stopping or de-rating the wind turbine. A control system configured to perform the above control method, and a wind turbine comprising such system are also disclosed.Type: ApplicationFiled: October 1, 2010Publication date: April 14, 2011Applicant: Vestas Wind Systems A/SInventors: Erik Carl Lehnskov Miranda, Imad Abdallah, Poul Brandt Christensen, Ali Zaib, Thomas Tvilum Bachmann
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Publication number: 20100283246Abstract: A method of controlling a wind turbine having a rotor and a generator for producing power, the wind turbine being designed for a nominal load, the method comprising the steps of: determining a current load acting on at least a part of the wind turbine; calculating a load error, the load error representing the difference between the nominal load and the current load; controlling the wind turbine based on the load error; wherein the step of controlling the wind turbine comprises altering a parameter of the wind turbine so that the power or torque produced by the generator is altered.Type: ApplicationFiled: April 30, 2010Publication date: November 11, 2010Applicant: VESTAS WIND SYSTEMS A/SInventor: Poul Brandt Christensen
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Publication number: 20100117361Abstract: A wind turbine includes a rotor having one or more rotor blades, a pitch system for controlling the pitch angle of the one or more rotor blades, the pitch system having at least one pitch actuator, a pitch controller for generating pitch actuator control signals and sensor elements for establishing values of pitch performance parameters, and a compensation controller to compensate for disparities between the pitch actuator control signals and the values of pitch performance parameters, according to a control algorithm. The compensation controller is arranged to adjust parameters of the control algorithm of the compensation controller in dependency of the disparities.Type: ApplicationFiled: January 14, 2010Publication date: May 13, 2010Inventor: Poul Brandt Christensen