Patent application number | Description | Published |
20090140458 | POROUS TEMPLATE AND IMPRINTING STACK FOR NANO-IMPRINT LITHOGRAPHY - An imprint lithography template or imprinting stack includes a porous material defining a multiplicity of pores with an average pore size of at least about 0.4 nm. A porosity of the porous material is at least about 10%. The porous template, the porous imprinting stack, or both may be used in an imprint lithography process to facilitate diffusion of gas trapped between the template and the imprinting stack into the template, the imprinting stack or both, such that polymerizable material between the imprinting stack and the template rapidly forms a substantially continuous layer between the imprinting stack and the template. | 06-04-2009 |
20100059914 | Chucking System Comprising an Array of Fluid Chambers - The present invention is directed towards a chucking system to hold a substrate, said system including, inter alia, a chuck body having first and second opposed sides, said first side including an array of fluid chambers arranged in rows and columns, said fluid chambers each comprising first and second spaced-apart recesses defining first and second spaced-apart support regions, with said first support region cincturing said second support region and said first and second recesses, and said second support region cincturing said second recess, with said substrate resting against said first and second support regions, with said first recess and a portion of said substrate in superimposition therewith defining a first chamber and said second recess and a portion of said substrate in superimposition therewith defining a second chamber, with each column of said first chambers and each row of said second chambers being in fluid communication with a differing source of fluid to control a flow of fluid in said array of fluid chambers. | 03-11-2010 |
20100259745 | METHOD FOR OBTAINING FORCE COMBINATIONS FOR TEMPLATE DEFORMATION USING NULLSPACE AND METHODS OPTIMIZATION TECHNIQUES - The present invention is directed towards a method for determining deformation parameters that a patterned device would undergo to minimize dimensional variations between a recorded pattern thereon and a reference pattern, the method including, inter alia, comparing spatial variation between features of the recorded pattern with respect to corresponding features of the reference pattern; and determining deformation forces to apply to the patterned device to attenuate the dimensional variations, with the forces having predetermined constraints, wherein a summation of a magnitude of the forces is substantially zero and a summation of moment of the forces is substantially zero. | 10-14-2010 |
20100314803 | Chucking System for Nano-Manufacturing - A chucking system may include a plurality of discrete vacuum sections. The size of at least one vacuum section may be configured to be substantially similar to size of a strained region of the substrate. The strained region of the substrate is a localized deformation in the substrate due to separation force applied during a nano-imprint lithography process. | 12-16-2010 |
20110014314 | Chucking System for Nano-Manufacturing - Chucking mechanisms may include a plurality of chucking sections respectively connecting to a pressure control device to generate individual chucking forces. The individual chucking forces of the chucking sections may be varied by the pressure control device such that a magnitude of separation force is reduced for an imprint lithography system. | 01-20-2011 |
20110084417 | LARGE AREA LINEAR ARRAY NANOIMPRINTING - Systems and methods for imprinting and aligning an imprint lithography template with a field on a substrate are described. The field of the substrate may include an elongated side, and alignment sensitivity on the elongated side may be intentionally minimized. | 04-14-2011 |
20110260361 | SAFE DEPARATION FOR NANO IMPRINTING - Control of lateral strain and lateral strain ratio (d | 10-27-2011 |
20150131072 | LOW CONTACT IMPRINT LITHOGRAPHY TEMPLATE CHUCK SYSTEM FOR IMPROVED OVERLAY CORRECTION - Imprint lithography template chucks and related systems and methods are provided that substantially maintain structural support functions while significantly enhancing imprint quality functions. The chucks incorporate dynamic vacuum seals to substantially reduce template contact during alignment and distortion correction while still providing good structural support upon separation. | 05-14-2015 |
Patent application number | Description | Published |
20120218676 | Hybrid Circuit Breaker - A hybrid circuit breaker, including a first circuit that includes: a main current path which includes a mechanical switch element, a commutation path arranged in parallel with the main current path and including a controllable semi-conductor switch element. The breaker also includes a first capacitor provided in the commutation path in series with the controllable semi-conductor switch element, and a second circuit, arranged in series with the first circuit and including a second capacitor and an inductance-generating element arranged in series with each other. | 08-30-2012 |
20130016541 | AC/DC CONVERTER STATION AND A METHOD OF OPERATING AN AC/DC CONVERTER STATIONAANM Norrga; StaffanAACI StockholmAACO SEAAGP Norrga; Staffan Stockholm SEAANM Jonsson; Tomas UAACI VasterasAACO SEAAGP Jonsson; Tomas U Vasteras SEAANM Shukla; AnshumanAACI VasterasAACO SEAAGP Shukla; Anshuman Vasteras SE - The present invention relates to an AC/DC converter station for interconnection of a DC transmission line and an AC network, the AC/DC converter station including an AC/DC converter and a control system configured to control the AC/DC converter. The AC/DC converter station comprises a capacitor connected in series between the AC/DC converter and the AC network, and a voltage measurement device arranged to measure the voltage across the capacitor. The AC/DC converter further comprises a control system connected to the voltage measurement device and arranged to receive, from the voltage measurement device, a signal indicative of a measured voltage. The control system is arranged to perform the control of the AC/DC converter in dependence of the signal received from the voltage measurement device. The invention further relates to a method of operating an AC/DC converter station. | 01-17-2013 |
20130021708 | Hybrid Circuit Breaker - A hybrid circuit breaker for interrupting a fault current in an electrical circuit line having a line impedance, the hybrid circuit breaker including a mechanical circuit breaker adapted to interrupt the line upon detecting the fault current, a semiconductor device arranged in parallel with the mechanical circuit breaker to conduct the fault current when the mechanical circuit breaker is disconnected, a branch connected between the electrical circuit line and ground, the branch including an impedance unit and a control unit configured, upon detecting the fault current, to connect the impedance unit in parallel with the line impedance. | 01-24-2013 |
20130027995 | MODULAR MULTI-LEVEL POWER CONVERTER WITH SECOND AND THIRD ORDER HARMONICS REDUCTION FILTER - A device for converting a DC voltage into an AC voltage includes a passive electronic filter having a first and second energy storage element, a third energy storage element placed between the first and second energy storage elements, a fourth energy storage element connected between a junction of the first energy storage element and the third energy storage element and an AC terminal and a fifth energy storage element connected between a junction of the second energy storage element and the third energy storage element and the AC terminal. The energy storage elements are of two different types, capacitive and inductive, with values selected to provide reduction of frequency components at two times the fundamental frequency of the AC voltage and at three times the fundamental frequency of the AC voltage. | 01-31-2013 |
20130070495 | AC/DC CONVERTER - The present invention relates to an AC/DC converter comprising at least two phase legs connected in series between first and second DC connection terminals of the AC/DC converter, wherein each phase leg comprises: an AC connection having first and second terminals arranged to connect the phase leg to a phase of an AC system; a phase branch comprising at least one converter cell and having first and second branch end terminals; and a capacitor. The capacitor is connected the between the first branch end terminal and the first AC connection terminal, so that the capacitor forms a DC blocking capacitor. The second AC terminal is connected to the second branch end terminal. The series connection of the phase legs between first and second DC connection terminal is such that a first series connection point in a phase leg is located between the first branch end terminal and the capacitor, while a second series connection point is located between the second branch end terminal and the second AC connection. The invention further relates to a method of operating such AC/DC converter. | 03-21-2013 |
Patent application number | Description | Published |
20100320763 | METHOD FOR DETERMINING A ROTOR POSITION OF AN ELECTRICAL GENERATOR IN A WIND TURBINE - A method for determining a rotor position of an electrical generator in a wind turbine is described comprising determining a voltage of the electrical generator, determining a rotor position angle estimate based on the voltage of the electrical generator, determining a subsequent rotor position angle estimate through a feedback loop, based on a combination of the voltage of the electrical generator and the rotor position angle estimate. Further, a method to real time track encoder health is described comprising determining the phase angle of a reference voltage, determining the angle difference between the rotor position and the reference voltage, and determining the differentiation of the angle difference. | 12-23-2010 |
20100327585 | Control System for an Electrical Generator and Method for Controlling an Electrical Generator - A method for validating and initializing a control system for an electrical generator connected to a power converter in a wind turbine. The method may include generating a first parameter value representing control signal for controlling the stator flux of a stator of the electrical generator, measuring a second parameter value specifying an electrical operational characteristic of the electrical generator, and determining an accuracy level of the control signal based on the first parameter value and the second parameter value, wherein the accuracy level of the control signal has to fall within a predefined threshold for the control system to be validated. | 12-30-2010 |
20110106325 | CONTROLLER ARRANGEMENT OF AN ELECTRICAL POWER TRANSFER SYSTEM OF A WIND TURBINE - A controller arrangement of an electrical power transfer system ( | 05-05-2011 |
20110109279 | METHOD FOR DETERMINING A ROTOR POSITION OF AN ELECTRICAL GENERATOR IN A WIND TURBINE - A method for determining a rotor position of an electrical generator in a wind turbine is described comprising determining a voltage of the electrical generator, determining a rotor position angle estimate based on the voltage of the electrical generator, determining a subsequent rotor position angle estimate through a feedback loop, based on a combination of the voltage of the electrical generator and the rotor position angle estimate. Further, a method to real time track encoder health is described comprising determining the phase angle of a reference voltage, determining the angle difference between the rotor position and the reference voltage, and determining the differentiation of the angle difference. | 05-12-2011 |
20110148198 | POWER CONVERSION SYSTEM AND METHOD - A power conversion system for converting electrical power from at least one power source includes a plurality of converter chains which couple the at least one power source to at least one load. At least two of the converter chains comprise an associated dissipating unit. The dissipating units are coupled via at least one switch. A controller is arranged to control the at least one switch to route power to be dissipated from one of the converter chains to the converter chain's associated dissipating unit, or to at least one of the other dissipating units, or to the converter chain's associated dissipating unit and to at least one of the other dissipating units, to cause corresponding dissipation of the power to be dissipated. | 06-23-2011 |
20110248565 | METHOD AND APPARATUS FOR DYNAMIC LOAD SHARING - A method for providing dynamic load sharing between a first and a second three phase system is disclosed, wherein the first and second three phase system are connected to a first and second three phase interleaved winding in a generator. The method comprises determining a first q-axis control signal for the first three phase system and a second q-axis control signal for the second three phase system based on a torque and/or power demand for the generator, determining a first d-axis control signal for the first three phase system and a second d-axis control signal for the second three phase system based on a coupling effect between the first and second three phase systems, and adjusting the q-axis control signals and d-axis control signals by including at least one feed forward compensation signal, wherein said at least one feed forward compensation signal is based on a coupling effect between the first and second three phase systems. | 10-13-2011 |
20120211983 | METHOD AND SYSTEM FOR OPERATING AN ELECTROMECHANICALGENERATOR - A method for operating an electromechanical generator is provided, the method comprising: determining a magnetic field reference parameter based on an electromagnetic power reference representing a desired output of the electromechanical generator, determining a scaling factor for adjusting an air-gap magnetization level of the electromechanical generator to reduce loss in operating the electromechanical generator, modifying the magnetic field reference parameter with the scaling factor; and operating the electromechanical generator based on at least the modified magnetic field reference parameter. | 08-23-2012 |
20120217747 | METHOD OF CONTROLLING A WIND TURBINE GENERATOR AND APPARATUS FOR CONTROLLING ELECTRIC POWER GENERATED BY A WIND TURBINE GENERATOR - A method of controlling a wind turbine generator is provided, the wind turbine generator converting mechanical energy to electrical. The method comprises: determining an electromagnetic power reference representing the electromagnetic power generated by the wind turbine generator, wherein the electromagnetic power reference is determined based on a desired output of the wind turbine generator; controlling the electrical power generated by the wind turbine generator using a control signal, wherein the control signal is derived from the electromagnetic power reference and is modified in dependence on an inverse power function of the wind turbine generator by incorporating minimal copper loss constraint and stator voltage limiting constraint such that non-linearity of the wind turbine generator plant is compensated in the control loop and it operates at its maximum efficiency. One effect of the method is that classical linear control loop design can be employed in spite of the plant being a non-linear identity. | 08-30-2012 |
20120217824 | VARIABLE SPEED WIND TURBINE, AND A METHOD FOR OPERATING THE VARIABLE SPEED WIND TURBINE DURING A POWER IMBALANCE EVENT - A variable speed wind turbine is provided. The wind turbine comprises a generator, a power converter for converting at least a portion of electrical power generated by the generator, an energy management arrangement coupled to the power converter, the energy management arrangement comprises an energy storage unit, and a controller. The controller is adapted to detect a power imbalance event and to transfer at least a portion of excess electrical energy generated by the generator to the energy storage unit to be stored therein when the power imbalance event is detected. | 08-30-2012 |
20120268081 | DIRECT POWER AND STATOR FLUX VECTOR CONTROL OF A GENERATOR FOR WIND ENERGY CONVERSION SYSTEM - A method for controlling a variable speed wind turbine generator is disclosed. The generator is connected to a power converter comprising switches. The generator comprises a stator and a set of terminals connected to the stator and to the switches of the power converter. The method comprises: determining a stator flux reference value corresponding to a generator power of a desired magnitude, determining an estimated stator flux value corresponding to an actual generator power, determining a difference between the determined stator flux reference value and the estimated stator flux value, and operating said switches in correspondence to the determined stator flux reference value and the estimated stator flux value to adapt at least one stator electrical quantity to obtain said desired generator power magnitude. | 10-25-2012 |
20130009611 | DIRECT POWER AND STATOR FLUX VECTOR CONTROL OF A GENERATOR FOR WIND ENERGY CONVERSION SYSTEM - A method for controlling a variable speed wind turbine generator is disclosed. The generator is connected to a power converter comprising switches. The generator comprises a stator and a set of terminals connected to the stator and to the switches of the power converter. The method comprises: determining a stator flux reference value corresponding to a generator power of a desired magnitude, determining an estimated stator flux value corresponding to an actual generator power, determining a difference between the determined stator flux reference value and the estimated stator flux value, and operating said switches in correspondence to the determined stator flux reference value and the estimated stator flux value to adapt at least one stator electrical quantity to obtain said desired generator power magnitude. | 01-10-2013 |
20130093375 | METHOD OF POSITION SENSORLESS CONTROL OF AN ELECTRICAL MACHINE - A position sensorless control methodology for electrical machines using high frequency flux vector signal injection in the estimated rotor flux rotational reference frame is provided. In one aspect, the estimated position error function is derived directly from the stator flux equation without any simplification. The method is applicable for electrical generator motoring mode operation from standstill and power generation mode operation. | 04-18-2013 |
20130147442 | Direct power and stator flux vector control of a generator for wind energy conversion system - A method for controlling a variable speed wind turbine generator is disclosed. The generator is connected to a power converter comprising switches. The generator comprises a stator and a set of terminals connected to the stator and to the switches of the power converter. The method comprises: determining a stator flux reference value corresponding to a generator power of a desired magnitude, determining an estimated stator flux value corresponding to an actual generator power, determining a difference between the determined stator flux reference value and the estimated stator flux value, and operating said switches in correspondence to the determined stator flux reference value and the estimated stator flux value to adapt at least one stator electrical quantity to obtain said desired generator power magnitude. | 06-13-2013 |
20130154262 | QUICK START-UP OF WIND TURBINE GENERATORS - A wind farm is provided that is capable of quickly starting up without delay after an electrical grid becomes available after an outage. According to one embodiment, the wind farm comprises one or more main WTGs and an auxiliary WTG having a substantially lower start-up energy requirement than the one or more main WTGs. The auxiliary WTG is coupled to supply power to the one or more main WTGs to prepare the one or more main WTGs for start-up. | 06-20-2013 |
20130187384 | METHOD OF OPERATING A WIND TURBINE, WIND TURBINE, WIND TURBINE CONTROLLING SYSTEM, AND PROCESSING SYSTEM - According to an embodiment, a method of operating a wind turbine comprising a DC-to-AC voltage converter is provided, the wind turbine being connectable to a grid via the DC-to-AC voltage converter, the method comprising: determining a line voltage of a power line connecting the DC-to-AC voltage converter to the grid; if the determined line voltage exceeds a predefined voltage threshold value, injecting reactive current into the power line, wherein the amount of reactive current injected is chosen such that an output voltage of the DC-to-AC voltage converter is kept within a predetermined voltage range. | 07-25-2013 |
20130200620 | WIND TURBINE - A wind turbine is provided. The wind turbine includes a generator, an output thereof being connectable to a power grid via a power transmission path, the power transmission path comprising a generator side converter coupled to the output of the generator, a grid side converter coupled to the power grid, and a DC link coupled between the generator side converter and the grid side converter. For diverting the generator power, a load dump arrangement is provided which includes at least one resistor, a plurality of switches, and a plurality of electrical connections which electrically connect the at least one resistor to the output of the generator and across the DC link via the plurality of switches. One common and configurable load dump is used for both converter system failures and grid failures. As compared to two separate load dumps for converter failures and grid failures, the single load dump will require a smaller space for a wind turbine. Thus, the weight and size of the power converter system may be reduced. | 08-08-2013 |
20130265013 | PERMANENT MAGNET GENERATOR INDUCTANCE PROFILE IDENTIFICATION - Parameters of PM machines, especially for IPM machine, are known to vary by significant amounts. This affects the controllability of such machines, which may lead to reduced power loading capability and increased losses. The present invention relates to a method for PM machine inductance profile identification based on voltage mode stator flux observation which could be easily integrated to the generator start-up process in wind turbine application for both stator flux vector feedback control system and current vector feedback control system. | 10-10-2013 |
20130313826 | WIND TURBINE GENERATOR - A system for a wind turbine generator comprising: a set of voltage limiting elements, and a controller configured to bypass the voltage limiting elements when a line voltage is below a predetermined threshold, and configured to connect each voltage limiting element in series between a grid side converter and a turbine transformer of the wind turbine generator, and to determine a current control reference signal for controlling the grid side converter (to generate a determined current) when the line voltage is above the predetermined threshold. | 11-28-2013 |
20140001759 | METHOD OF OPERATING A WIND TURBINE AS WELL AS A SYSTEM SUITABLE THEREFORE | 01-02-2014 |
20140008912 | METHOD OF OPERATING A WIND TURBINE AS WELL AS A SYSTEM SUITABLE THEREFOR - According to a method of the present invention, a method of operating a wind turbine comprising a power generator, a generator side converter connected to the power generator, a line side converter connected to a power grid through power components, and a DC-link connected between the generator side converter and the line side converter is provided, the method comprising: monitoring the grid voltages on the power grid for overvoltage events; if an overvoltage event is detected, operating the line side converter in an overmodulation range for at least a part of the duration of the overvoltage event. | 01-09-2014 |
20140122011 | METHOD FOR DIAGNOSTIC MONITORING OF A WIND TURBINE GENERATOR SYSTEM - A method for diagnostic monitoring of a wind turbine generator system, said wind turbine generator system comprising a generator, a drive train, and a number of sensors for providing signals and a control system. The method comprising the selection of three sets of signals from said sensors. From the three sets of signals three conditioned sets of signals are obtained by high pass filtering said first set of signals, low pass filtering the second set of signals, and forming a moving average value on the third set of signals. Based on each of said first, second and third set of conditioned signals an evaluation is performed in order to determine a fault, where said evaluation comprises comparing the first, second and third set of conditioned signals with reference values. If said comparison indicates a fault an alarm is set. | 05-01-2014 |
20140217730 | POWER DISSIPATING ARRANGEMENT IN A WIND TURBINE - A power dissipating arrangement for dissipating power from a generator in a wind turbine is provided. The generator comprises a plurality of output terminals corresponding to a multi-phase output. The power dissipating arrangement comprises a plurality of dissipating units, a plurality of semiconductor switches, a trigger circuit for switching the semiconductor switches and a control unit for controlling the operation of the trigger circuit, thereby controlling the switching of the semiconductor switches. Each dissipating unit includes a first terminal and a second terminal. The first terminal of each dissipating unit is coupled to each output terminal of the generator. Each semiconductor switch includes a first terminal anode, a second terminal and a gate terminal. The first terminal of each semiconductor switch is coupled to the second terminal of each dissipating unit and the second terminal of the semiconductor switch is coupled to the second terminal of another dissipating unit, such that the second terminal of each dissipating unit is coupled to the first terminal of one semiconductor switch and the second terminal of another semiconductor switch. The trigger circuit is coupled to the gate terminal of the plurality of the semiconductor switches for switching the semi-conductor switches. | 08-07-2014 |
20140252768 | METHOD OF CONTROLLING A WIND TURBINE GENERATOR AND APPARATUS FOR CONTROLLING ELECTRIC POWER GENERATED BY A WIND TURBINE GENERATOR - A method of controlling a wind turbine generator is provided, the wind turbine generator converting mechanical energy to electrical. The method comprises: determining an electromagnetic power reference representing the electromagnetic power generated by the wind turbine generator, wherein the electromagnetic power reference is determined based on a desired output of the wind turbine generator; controlling the electrical power generated by the wind turbine generator using a control signal, wherein the control signal is derived from the electromagnetic power reference and is modified in dependence on an inverse power function of the wind turbine generator by incorporating minimal copper loss constraint and stator voltage limiting constraint such that non-linearity of the wind turbine generator is compensated in the control loop and it operates at its maximum efficiency. One effect of the method is that classical linear control loop design can be employed in spite of the plant being a non-linear identity. | 09-11-2014 |
20150124496 | METHOD FOR CHARGING A DC LINK OF A WIND TURBINE POWER ELECTRONIC CONVERTER - The present invention relates to a method for charging a DC link of a power converter included in a wind turbine generator, the wind turbine generator comprising a generator side converter connected to an electrical generator and a grid side converter connectable, or connected, to an electrical grid through a grid circuit breaker, and a converter controller arranged to control at least the DC link, the DC link having a DC voltage level, the wind turbine generator comprising a wind turbine rotor arranged to rotate the electrical generator, wherein the method comprises rotating the wind turbine rotor whereby the electrical generator generates electrical power, rectifying the electrical power through at least one diode of the generator side converter in order to pre-charge the DC link to a DC voltage level, closing the grid circuit breaker when the DC voltage level is greater than a threshold level. The invention also relates to a wind turbine generator with a converter controller for controlling pre-charging of a DC link. | 05-07-2015 |