Grid side inverter system arranged for controlling current injection when a phase locked loop controller is misaligned

    公开(公告)号:US11901734B2

    公开(公告)日:2024-02-13

    申请号:US17832223

    申请日:2022-06-03

    IPC分类号: H02J3/16

    CPC分类号: H02J3/16 H02J2300/28

    摘要: A grid side inverter system includes a grid side inverter, a phase locked loop controller arranged to determine a phase of a dq-frame dependent on a monitored grid voltage vector in the dq-frame and a reference grid voltage vector in the dq-frame, a current reference decision unit arranged to generate a reduction of at least one of an active and a reactive current reference, wherein a decision to generate the reduction is based on an electrical parameter relating to the phase difference of the monitored grid voltage vector and the PLL vector, a current controller arranged to determine control signals for the grid side inverter for controlling generation of active and reactive power to the grid dependent on the active and reactive current references and monitored active and a reactive grid currents in the dq-frame.

    Current dispatching for power plant control

    公开(公告)号:US11916392B2

    公开(公告)日:2024-02-27

    申请号:US17286802

    申请日:2019-08-20

    IPC分类号: H02J3/38 H02J13/00 G05B15/02

    摘要: Embodiments provide for the control of a power plant including several generators by setting a reference frame for the generators with a first and a second axis; measuring a grid demand voltage at the shared connection point; determining active and reactive currents required at the shared connection point based on the grid demand voltage and grid codes; transforming the active and reactive currents required at the shared connection point to the reference frame where the first axis defines a first current set point and the second axis defines a second current set point; and dispatching the first and second current set points to generator controllers associated with each generator. Current set points may be generated for positive/negative frames, direct quadrature frames, real/imaginary frames and may be set evenly for all generators or adjusted per generator.

    Virtual synchronous generator with active damping

    公开(公告)号:US11715955B2

    公开(公告)日:2023-08-01

    申请号:US17419251

    申请日:2019-12-16

    摘要: The invention relates to a method for controlling a power generating unit such as a wind turbine which is configured as a virtual synchronous machine. Capacitor voltage signals obtained from voltage measurements of output capacitors are filtered in order to reduce a magnitude of an impedance peak and/or shift the impedance peak where the impedance peak is present in an impedance characteristic of the output of the power generating unit. Filter compensated voltage signals obtained from the output capacitors are combined with a voltage magnitude reference to obtain filtered capacitor voltage signals used for controlling the line side converter and thereby affect the impedance peak in a desired way.

    Method for handling sub-synchronous resonances

    公开(公告)号:US11411519B2

    公开(公告)日:2022-08-09

    申请号:US16590475

    申请日:2019-10-02

    摘要: The present invention relates to a method of controlling a doubly fed induction generator wind turbine converter system in case of a sub-synchronous resonance event, the method comprising the steps of detecting the sub-synchronous resonance event, and switching from a first control mode to a second control mode in response to detecting the predetermined event, wherein the second control mode comprises the step of setting at least one rotor current controller parameter on the basis of a generator speed of the doubly fed induction generator. The predetermined event may also be a fault ride through event. The present invention further relates to a doubly fed induction generator wind turbine converter system being capable of handling such events.

    Method for controlling a renewable power plant during voltage events

    公开(公告)号:US12051907B2

    公开(公告)日:2024-07-30

    申请号:US17801772

    申请日:2021-02-03

    IPC分类号: H02J3/38 H02J3/46

    摘要: Controlling a current injected to a power grid from a renewable power plant, in response to a voltage event in the power grid. At least a current at a point of common coupling between the renewable power plant and the power grid is determined and provided to a power plant controller (PPC). The PPC derives individual current setpoint corrections for at least some wind turbines, based on the determined current, and dispatches each derived current setpoint correction to wind turbine controllers of the corresponding wind turbines. The wind turbine controllers control a current output of the respective wind turbines, based on measurements of current and/or voltage at a point of connection between the wind turbine and an internal grid of the renewable power plant, and by taking into account the dispatched current setpoint correction.

    Power generating unit with virtual synchronous generator with current limitation

    公开(公告)号:US11863112B2

    公开(公告)日:2024-01-02

    申请号:US17628174

    申请日:2020-07-08

    IPC分类号: H02P9/00 H02P9/02

    CPC分类号: H02P9/006 H02P9/02

    摘要: The invention relates to controlling a power generating unit. Aspects of the invention include determining a virtual impedance value (Zvir), determining a virtual grid power (Pvsm) based on the virtual resistance value (Rvir) and the grid current (Igrid), determining a virtual synchronous machine rotational speed (ωVSM) and/or a synchronous machine angle (θVSM) of a virtual synchronous generator, and determining a voltage reference (Vabc) for controlling a line side converter to generate the desired reactive power (Qgrid) based on the virtual synchronous machine rotational speed or angle (ωVSM, θVSM), a virtual voltage (ΔVαβ, ΔVdq) and the voltage magnitude reference (Vqref).

    METHODS AND CONTROL SYSTEMS FOR VOLTAGE CONTROL OF RENEWABLE ENERGY GENERATORS

    公开(公告)号:US20230291204A1

    公开(公告)日:2023-09-14

    申请号:US18013837

    申请日:2021-06-03

    IPC分类号: H02J3/18 H02J3/38

    摘要: Aspects of the present invention relate to a method for controlling a plurality of renewable energy generators. The method comprises: determining preliminary reactive power set points for the generators based on a reactive power reference value; determining generator-based and voltage-based reactive power limits for the generators; generating dispatch signals for requesting reactive power from the generators based on the preliminary set point and the limits; and dispatching the dispatch signals to the generators. The generator-based reactive power limits correspond to the reactive power capability of the generator. The voltage-based limits are determined by: determining a terminal voltage of the generator; comparing the determined terminal voltage to a voltage limit; and determining the voltage-based reactive power limit based on the comparison.

    Estimating a characteristic of a wind turbine electrical signal

    公开(公告)号:US11143167B2

    公开(公告)日:2021-10-12

    申请号:US16472371

    申请日:2017-10-17

    IPC分类号: F03D17/00

    摘要: A method and apparatus for estimating a characteristic of a wind turbine electrical signal comprises buffering a sequence of sample values of the wind turbine electrical signal and a sequence of sample times corresponding with the sequence of sample values. The time periods represented by the sample times are variable. A sub-sequence of the buffered sample values to integrate is determined, based at least in part on a sum of the time periods. The characteristic is estimated by integrating the sample values in the sub-sequence.