公开(公告)号：US20200335972A1

公开(公告)日：2020-10-22

申请号：US16920872

申请日：2020-07-06

Applicant: Enphase Energy, Inc.

Inventor： Donald Richard Zimmanck

IPC: H02J3/18 ,  H02J3/16 ,  H02J3/38

Abstract: A method and apparatus for setting an impedance of a power conditioning unit (PCU). In one embodiment, the method comprises applying a disturbance to a virtual AC voltage produced by a power conditioning unit (PCU) that is coupled to a power grid, where the disturbance has a first phase; measuring a second phase of the applied disturbance on the power grid; comparing the second phase of the applied disturbance to the first phase of the disturbance; and adjusting, when the second phase differs from the first phase by more than a threshold amount, an impedance of the PCU.

公开(公告)号：US10787080B2

公开(公告)日：2020-09-29

申请号：US15514986

申请日：2015-09-28

Applicant: Bombardier Primove GmbH

Inventor： Rinaldo Arnold ,  Robert Czainski

IPC: H02J3/00 ,  B60L5/00 ,  B60M7/00 ,  B60L53/12 ,  H02J3/12 ,  H02J3/18 ,  H02J5/00

Abstract: Disclosed is a method of and control system for operating a circuit arrangement, in particular a circuit arrangement of an electric vehicle for inductive power transfer to the vehicle. The circuit arrangement includes at least one phase line with at least one field receiving arrangement and at least one compensating arrangement with a variable reactance, wherein at least one current-dependent cost function is evaluated, wherein the reactance is varied such that the cost function is optimized.

公开(公告)号：US20200287410A1

公开(公告)日：2020-09-10

申请号：US16764865

申请日：2018-04-08

Applicant: BEIJING ETECHWIN ELECTRIC CO., LTD.

Inventor： Shuaiyang Zhao ,  Yunhai Lan ,  Chengzhi Qin

IPC: H02J13/00 ,  H02J3/32 ,  H02J3/18 ,  H02H7/28 ,  H02H1/00 ,  G05B11/36

Abstract: Provided in the present invention are a microgrid control system and a microgrid, the microgrid control system comprising: a grid-connected switch, an energy router, a first controller and a second controller; the first controller controls the grid-connected switch and sends a first control instruction; the second controller receives the first control instruction and responds to the first control instruction for controlling the energy router.

公开(公告)号：US20200274360A1

公开(公告)日：2020-08-27

申请号：US16062888

申请日：2017-05-16

Applicant: VESTAS WIND SYSTEMS A/S

Inventor： Ciprian BIRIS ,  Uffe C. MERRILD ,  Leif Svinth CHRISTENSEN ,  Gert Karmisholt ANDERSEN

IPC: H02J3/18 ,  H02P9/00 ,  H02K7/18 ,  F03D7/02 ,  F03D9/25 ,  G05B15/02

Abstract: Aspects of the present invention relate to a method for controlling an amount of reactive current provided from a wind turbine generator to a power grid during an abnormal power grid event, said wind turbine generator comprising a doubly-fed induction generator having a rotor and a stator, and a power converter coupling the rotor to the power grid, the power converter comprising a grid-side inverter, wherein the method comprises the step of balancing the reactive current provided to the power grid between a reactive stator current and a reactive grid-side inverter current, wherein the reactive grid-side inverter current is controlled in accordance with a reactive current capacity of a grid breaker receiving the reactive current provided by the grid-side inverter. Aspects of the present invention also relate to a wind turbine generator being capable of performing the method.

公开(公告)号：US10756536B2

公开(公告)日：2020-08-25

申请号：US15496251

申请日：2017-04-25

Applicant: Aggreko Deutschland GmbH

Inventor： Thomas Kral ,  Christian Hans ,  Peter Merk

IPC: H02H7/28 ,  H02J3/38 ,  H02J3/18 ,  H02M7/537 ,  H02M1/32

Abstract: A system for handling short circuits on an electrical network comprising parallel operated units which are droop controlled for active and reactive power sharing and connected to each other via impedances and protection switches for detecting and handling a short circuit on the electrical network and for disconnecting the faulty part of the electrical network, said units including a DC-source and a grid forming voltage source inverter controlled by a cascaded control structure with an inner voltage control loop and a short circuit control for limiting the output current by changing the output voltage at the output terminals of the inverter as a function of the measured output current and a desired droop voltage provided by a droop controller for voltage and frequency power sharing.

公开(公告)号：US10749343B2

公开(公告)日：2020-08-18

申请号：US15527257

申请日：2015-02-02

Applicant: INGETEAM POWER TECHNOLOGY, S.A.

Inventor： Beatriz Gil Lizarbe ,  Carlos Girones Remirez ,  Eduardo Sanz Ceballos

IPC: H02J3/24 ,  H02J3/38 ,  H02J3/18 ,  H02P9/00

Abstract: A method which is suitable for a system having a frequency converter and a generator, both of which are connected to a power grid, includes obtaining sub-synchronous components of the grid voltage and determining damping current set points according to the sub-synchronous components to compensate for sub-synchronous resonances of the grid. Damping current set points are determined by receiving the sub-synchronous components of the grid voltage and returning damping current set points as outputs. A variable damping gain is adjusted according to the sub-synchronous frequency of the grid, such that the required compensation level can be adapted to the frequency converter for damping sub-synchronous resonance of the grid.

公开(公告)号：US10742149B1

公开(公告)日：2020-08-11

申请号：US16390547

申请日：2019-04-22

Applicant: General Electric Company

Inventor： Kasi Viswanadha Raju Gadiraju ,  Olive Ray ,  Kapil Jha ,  Yashomani Yashodhan Kolhatkar

IPC: H02P9/42 ,  H02P9/00 ,  H02P9/10 ,  H02P9/30 ,  H02P101/15 ,  H02M5/458 ,  H02M1/42 ,  H02J3/18 ,  F03D9/25 ,  H02J3/38

Abstract: A method and associated system for operating a power generation system to provide real and reactive power to a load includes, with a power converter having switching elements, receiving power from a generator and generating the reactive power within an operating range of generator rotor speed. As the generator rotor speed changes and approaches synchronous speed, a control command is generated to decrease a switching frequency of the switching elements in the power converter from a first switching frequency to a second switching frequency, wherein the reactive power output of the power converter is maintained or increased at the second switching frequency.

公开(公告)号：US10734808B2

公开(公告)日：2020-08-04

申请号：US16072508

申请日：2017-01-30

Applicant: Maschinenfabrik Reinhausen GmbH

Inventor： Haijun Feng ,  Alexei Babizki

IPC: G05D3/12 ,  G05D5/00 ,  G05D9/00 ,  G05D11/00 ,  G05D17/00 ,  H02J3/06 ,  H02J3/18 ,  H02J3/24 ,  G05B13/04

Abstract: A method of controlling a regulating transformer with a settable translation ratio, switchable between a first and second AC-mains includes the following operations: detecting phasor data of phasors of the first and/or second AC-mains; determining an equivalent circuit diagram with equivalent circuit diagram parameters for the first AC-mains; determining a load model with load model parameters for the second AC-mains; determining the equivalent circuit diagram parameters and the load model parameters from the phasor data; and when switching over to a desired translation ratio is to take place: predicting a working point of the second AC-mains for the desired translation ratio; checking a stability criterion in the second AC-mains for the predicted working point; and switching over to the desired translation ratio is carried out upon the stability criterion being fulfilled, but otherwise not switching over to the desired translation ratio.

公开(公告)号：US20200244070A1

公开(公告)日：2020-07-30

申请号：US16753311

申请日：2018-11-16

Applicant: Ørsted Wind Power A/S

Inventor： Troels Stybe SØRENSEN

IPC: H02J3/38 ,  H02J3/32 ,  H02J3/18 ,  H02J3/00 ,  F03D7/04 ,  F03D9/25 ,  F03D7/02

Abstract: Methods for black-starting an electrical grid (2) are described herein. For example, a method comprises disconnecting the wind farm (1) from the grid at a first location, said first location being located between the electrical grid (2) and the energy storage (16) with the associated converter (17), energizing the AC export cable (12) using said energy storage (16) and the associated converter (17), energizing at least one part of the wind farm electrical infrastructure via said export cable (12) using said energy storage (16) and the associated converter (17), re-establishing energy supply to said wind farm electrical infrastructure by said wind turbine generators (3, 4), and reconnecting the wind farm (1) to said electrical grid (2) at said first location.

公开(公告)号：US20200244062A1

公开(公告)日：2020-07-30

申请号：US16852048

申请日：2020-04-17

Applicant: Smart Wires Inc.

Inventor： Haroon Inam ,  Debrup Das ,  Amrit Iyer

IPC: H02H3/16 ,  H02J3/06 ,  H02J3/18 ,  H02H7/16 ,  H02H9/04

Abstract: Flexible AC transmission system (FACTS) enabling distributed controls is a requirement for power transmission and distribution, to improve line balancing and distribution efficiency. These FACTS devices are electronic circuits that vary in the type of services they provide. All FACTS devices have internal circuitry to handle fault currents. Most of these circuits are unique in design for each manufacturer, which make these FACTS devices non-modular, non-interchangeable, expensive and heavy. One of the most versatile FACTS device is the static synchronous series compensator (SSSC), which is used to inject impedance into the transmission lines to change the power flow characteristics. The addition of integrated fault current handling circuitry makes the SSSC and similar FACTS devices unwieldy, heavy, and not a viable solution for distributed control. What is disclosed are modifications to FACTS devices that move the fault current protection external to the FACTS device and make them modular and re-usable.