Patent application number | Description | Published |
20090212564 | Method and apparatus for assembling electrical machines - A method of assembling an electrical machine includes programming at least one processor with a stator flux vector estimation scheme. The electrical machine has a stator at least partially extending around a rotor. The electrical machine is electrically coupled to an electric power system. The electric power system transmits at least one phase of electric power to and from the electrical machine with at least partial power conversion. The stator flux vector estimation scheme is programmed to generate at least one stator back-electromagnetic force (back-EMF) signal and to generate at least one stator flux vector signal using the at least one stator back-EMF signal. The at least one stator flux vector signal at least partially represents an estimated rotor position. The method also includes coupling at least one output device in data communication with the at least one processor. | 08-27-2009 |
20100133831 | METHOD AND APPARATUS FOR CONTROLLING A WIND TURBINE - A control system for a wind turbine, the control system having at least one measurement device configured to measure at least one operating condition of the wind turbine and a first controller. The first controller is configured to calculate an operating limit of the wind turbine based on the measured operating condition and to adjust the operating limit based on a limiting condition of a component of the wind turbine. | 06-03-2010 |
20100133904 | DC BUS VOLTAGE CONTROL FOR TWO STAGE SOLAR CONVERTER - Systems, methods, and apparatus for supplying AC power to an AC power grid from a DC power source, such as a photovoltaic (PV) array are disclosed. The systems and methods can include a converter coupled to the DC power source that provides DC power to a DC bus at a DC bus voltage. The systems and methods can further include an inverter coupled to the DC bus for converting the DC power of the DC bus to an output AC power. The systems and methods can further include a control system configured to regulate the DC bus voltage of the DC bus to operate at a variable DC bus voltage setpoint. The control system can adjust the DC bus voltage setpoint based at least in part on the DC bus voltage and the output AC current of the inverter. | 06-03-2010 |
20110096579 | DC BUS VOLTAGE CONTROL FOR TWO STAGE SOLAR CONVERTER - Systems, methods, and apparatus for supplying AC power to an AC power grid from a DC power source, such as a photovoltaic (PV) array are disclosed. The systems and methods can include a converter coupled to the DC power source that provides DC power to a DC bus at a DC bus voltage. The systems and methods can further include an inverter coupled to the DC bus for converting the DC power of the DC bus to an output AC power. The systems and methods can further include a control system configured to regulate the DC bus voltage of the DC bus to operate at a variable DC bus voltage setpoint. The control system can adjust the DC bus voltage setpoint based at least in part on the DC bus voltage and the output AC current of the inverter. | 04-28-2011 |
20110101689 | METHOD AND APPARATUS FOR GENERATING POWER IN A WIND TURBINE - A power converter for a wind turbine including an array of switching devices and a control module having a current damping device. The control module is configured to control a switching behavior of the array of switching devices and to receive a current having a first frequency component from the wind turbine. The current damping device is configured to reduce an amplitude of the first frequency component. | 05-05-2011 |
20110137474 | METHOD AND SYSTEMS FOR OPERATING A WIND TURBINE - A method for controlling operation of a wind turbine included within a power generation and delivery system is described. The method includes measuring at least one operating condition of the power generation and delivery system. The method also includes transmitting, to a power limiter system, an operating condition feedback signal that corresponds to the operating condition. The method also includes analyzing the operating condition feedback signal to identify an occurrence of a grid contingency event and generating a real current command signal corresponding to an occurrence of a grid contingency event. The method also includes transmitting the real current command signal to a controller and applying the real current command signal to power converter performance to facilitate reducing pole-slipping. The method also includes storing, in a memory, at least one variable corresponding to the operating condition upon the occurrence of a grid contingency event. | 06-09-2011 |
20110141637 | CIRCUIT FOR USE WITH ENERGY CONVERTER - In an embodiment, the circuit includes: a first switch serially connected to a first discharge resistor, the first switch and the first discharge resistor connected to a positive DC bus; a second switch serially connected to a second discharge resistor, the second switch and the second discharge resistor connected to a negative DC bus; and a capacitor bank for storing a positive and a negative DC voltage, the capacitor bank including a first capacitor in parallel with the first switch and the first discharge resistor, and a second capacitor in parallel with the second switch and the second discharge resistor, wherein the first switch operates independently from the second switch to discharge the positive DC voltage through the first discharge resistor and the second switch operates independently from the first switch to discharge the negative DC voltage through the second discharge resistor. | 06-16-2011 |
20120010759 | METHOD AND SYSTEMS FOR OPERATING A WIND TURBINE - A method for controlling operation of a wind turbine included within a power generation and delivery system is described. The method includes measuring at least one operating condition of the power generation and delivery system. The method also includes transmitting, to a power limiter system, an operating condition feedback signal that corresponds to the operating condition. The method also includes analyzing the operating condition feedback signal to identify an occurrence of a grid contingency event and generating a real current command signal corresponding to an occurrence of a grid contingency event. The method also includes transmitting the real current command signal to a controller and applying the real current command signal to power converter performance to facilitate reducing pole-slipping. The method also includes storing, in a memory, at least one variable corresponding to the operating condition upon the occurrence of a grid contingency event. | 01-12-2012 |
20130049363 | PERMANENT MAGNET MACHINE CONTROL SYSTEM - A permanent magnet (PM) machine system is provided having a PM machine and a controller in communication with the PM machine. The PM machine has a q-axis voltage feedback signal and a pullout torque that represents a peak torque that the PM machine generates. The controller includes a q-axis current regulator that produces a commanded q-axis voltage that is supplied to the PM machine. The controller also includes at least one control logic for monitoring the q-axis voltage feedback signal of the PM machine. | 02-28-2013 |
20130054043 | FAULT DETECTION SYSTEM FOR A GENERATOR - A fault detection system is provided, and includes a generator, a power converter, a breaker, a current monitoring device, and a control module. The power converter is selectively connected to the generator and is selectively activated to produce a test voltage. The breaker is located between the generator and the power converter for selectively connecting the generator to the power converter. The breaker includes an open position and a closed position. The current monitoring device is located between the generator and the power converter. The current monitoring device measures a line current between the generator and the power converter. The control module is in communication with the current monitoring device and the power converter. The control module has a memory with a threshold current value. | 02-28-2013 |
20130107586 | SYSTEM FOR IMPROVED WIND TURBINE GENERATOR PERFORMANCE | 05-02-2013 |
20130128632 | NEUTRAL POINT CLAMPED CONVERTER CONTROL SYSTEM AND CONTROL METHOD AND COMPENSATION UNIT - A control system includes a fundamental control unit, first and second compensation control units, a switch control unit, and a switch implementation unit. The fundamental control unit generates fundamental commands to implement fundamental power conversion operation for a converter. The first compensation control unit generates a first compensation signal for injection into the fundamental command to balance neutral point voltage when the converter is in operation in a first state. The second compensation control unit generates a second compensation signal for injection into the fundamental command to balance neutral point voltage when the converter is in operation in a second state. The switch control unit detects first and second states of the converter and provides first and second switch signals respectively. The switch implementation unit switches the fundamental control unit to communicate with the first and second compensation control units according to the first and second switch signals respectively. | 05-23-2013 |
20130207622 | SYSTEM AND METHOD FOR REACTIVE POWER REGULATION - A system and method are provided for performing reactive power control. The system includes a power converter and a controller coupled to the power converter. The power converter is configured to convert a first form of electric power generated from the power source to a second form of electric power suitable to be distributed by the electrical grid. The controller is configured to monitor the electric power transmitted between the power converter and the electrical grid. The controller is further configured to decouple a positive sequence component and a negative sequence component from the monitored electric power. The controller is further configured to perform a positive reactive power control and a negative reactive power control with respect to the decoupled positive and negative sequence components. The controller is further configured to transmit a control signal to the power converter based on the positive and negative reactive power control. | 08-15-2013 |
20140062424 | SYSTEM AND METHOD FOR CONTROLLING A DUAL-FED INDUCTION GENERATOR IN RESPONSE TO HIGH-VOLTAGE GRID EVENTS - In one aspect, a method for controlling a dual-fed induction generator (DFIG) during a high-voltage grid event is provided. The method includes setting, by a controller, an output of a closed-loop portion of a rotor current regulator to a fixed value such that a predictive feed-forward path sets an internal voltage for the DFIG; and detecting, by the controller, a condition of high dc voltage on a dc link or a condition predictive of high dc voltage on the dc link, and in response reduce a rotor torque producing current command to approximately zero, wherein the dc link connects a line-side converter connected to a system bus and a rotor-side converter connected to a rotor of the DFIG. | 03-06-2014 |
20140070535 | METHOD AND SYSTEMS FOR OPERATING A WIND TURBINE USING DYNAMIC BRAKING IN RESPONSE TO A GRID EVENT - A method and system for dissipating energy in a direct current (dc) bus of a doubly-fed induction generator (DFIG) converter during a grid event is described. In one aspect, the method comprises monitoring operating conditions of an electrical system, the electrical system comprising at least a DFIG generator and a line side converter and a rotor side converter connected by a dc bus having a dynamic brake connected thereto; detecting an overvoltage on the dc bus or a condition indicative of an overvoltage on the dc link is detected, the overvoltage on the dc bus or condition indicative of the overvoltage caused by a grid event; and causing energy in the dc link to be dissipated using the dynamic brake. | 03-13-2014 |
20140070536 | VOLTAGE CONTROL IN A DOUBLY-FED INDUCTION GENERATOR WIND TURBINE SYSTEM - Systems and methods for regulating voltage in a doubly fed induction generator (DFIG) system are provided. More particularly, the voltage of the auxiliary power feed in a DFIG wind turbine system can be regulated by outputting reactive power from a power converter to a reactive element coupled between the auxiliary power feed and a stator bus. The reactive element can include a winding of the transformer used to couple the wind turbine system to the electrical grid and/or an inductive element coupled between the output of the power converter and the stator bus. The voltage of the auxiliary power feed can be maintained within a reduced operating range while an increased operating range can be provided for wind turbine system | 03-13-2014 |
20140204630 | CURRENT BALANCE CONTROL FOR NON-INTERLEAVED PARALLEL BRIDGE CIRCUITS IN POWER CONVERTER - Systems and methods for reducing current imbalance between parallel bridge circuits used in a power converter of a power generation system, such as a wind driven doubly fed induction generator (DFIG) system, are provided. The power converter can include a plurality of bridge circuits coupled in parallel to increase the output power capability of the system. Each of the bridge circuits can include a pair of switching elements, such as insulated gate bipolar transistors (IGBTs), coupled in series with one another. The switching elements of the parallel bridge circuits can be controlled, for instance, using control commands (e.g. pulse width modulation commands) according to a substantially non-interleaved switching pattern. The timing of the control commands according to the substantially non-interleaved switching pattern can be adjusted to reduce current imbalance between the parallel bridge circuits. | 07-24-2014 |
20140354244 | CONNECTION FOR IMPROVED CURRENT BALANCING IN A PARALLEL BRIDGE POWER CONVERTER - A power generation system may include a generator and a power converter coupled to the generator. The power converter may include a plurality of bridge circuits coupled in parallel. Each bridge circuit may be coupled to an inductor. In addition, the power converter may include a plurality of parallel shorting devices. The shorting devices may be coupled to the bridge circuits such that an impedance of the inductors is effectively coupled between the shorting devices and the generator. | 12-04-2014 |
20150084337 | SYSTEM AND METHOD FOR CONTROLLING SWITCHING ELEMENTS WITHIN A SINGLE-PHASE BRIDGE CIRCUIT - In one aspect, a method for controlling the operation of switching elements contained within a single-phase bridge circuit of a power convertor may include monitoring gate voltages of a first switching element and a second switching element of the single-phase bridge circuit and controlling the first and second switching elements so that each switching element is alternated between an activated state and a deactivated state. In addition, the method may include transmitting a gating command signal to adjust the first switching element from the deactivated state to the activated state when: a first gate drive command is received that is associated with switching the first switching element to the activated state; a second gate drive command is received that is associated with switching the second switching element to the deactivated state; and the gate voltage of the second switching element is less than a predetermined voltage threshold. | 03-26-2015 |
20150159625 | SYSTEM AND METHOD FOR CONTROLLING A WIND TURBINE SYSTEM - A method for controlling a wind turbine system may generally include controlling a wind turbine to operate at a speed and torque setting within a permissible operating region defined between maximum and minimum operating curves, receiving a speed de-rate request and/or a torque de-rate request to de-rate the wind turbine based on a limiting constraint of the wind turbine system, determining an adjusted speed setting and/or an adjusted torque setting for the wind turbine based on the speed de-rate request and/or the torque de-rate request, determining whether an adjustment of the wind turbine operation to the adjusted speed setting and/or the adjusted torque setting would place the turbine outside the permissible operating region and, if the adjustment would place the operation outside the permissible operating region, adjusting the speed setting and/or the torque setting to a new speed and/or torque setting defined along the maximum or minimum operating curve. | 06-11-2015 |
20150252784 | SYSTEM AND METHOD FOR INITIALIZING A STARTUP SEQUENCE OF A WIND TURBINE - The present subject matter is directed to a method for initializing a startup sequence of a wind turbine. The method includes a step of defining a plurality of operating conditions of the wind turbine. As such, upon satisfaction of the plurality of operating conditions, a run-ready signal may be generated, wherein the run-ready signal indicates a readiness of a power converter of the wind turbine to generate power. The method may also include defining a subset of the plurality of operating conditions, wherein the subset of operating conditions are independent of speed conditions of the wind turbine. Another step of the method includes generating a spin-ready signal for the wind turbine upon satisfaction of the subset of operating conditions. The method may also include controlling a rotor of the wind turbine based at least in part on the spin-ready signal. | 09-10-2015 |