A method for inertia response control of a grid-forming doubly-fed generator

Abstract

The application discloses a kind of inertia response control methods of network type doubly-fed generator, it is related to new energy power generation grid-connected control technical field, wherein method includes obtaining the active power reference value of doubly-fed generator foundation, actual active power and grid frequency, generates active power compensation through automatic active regulator, generates additional inertia power instruction through automatic inertia response regulator, and utilizes power dead zone to carry out coordinated control to active recovery process, further generates the active power reference value of network controller.This application forms the equivalent inertia response of no detection delay by the recovery time constant of automatic active regulator, and realizes adjustable inertia response amplitude by combining additional inertia power instruction, while avoiding the offset of inertia support by power recovery link, solve the problems of response delay, insufficient inertia support capacity and control link mutual influence of traditional doubly-fed generator inertia response.

Description

Technical Field

[0001] This invention relates to the field of grid-connected control technology for new energy power generation, and in particular to a method for controlling the inertia response of a grid-connected doubly-fed generator. Background Technology

[0002] Doubly fed induction generator (DFIG) wind turbines are widely used in onshore wind farms. Traditional DFIG turbines typically employ a grid-following control method based on phase-locked loops (PLLs), where the turbine operates in accordance with the voltage phase of the external power grid, and the active power is determined by maximum power point tracking (MPPT) commands or grid dispatch commands. With the increasing proportion of renewable energy integration, the capacity of the system's synchronous generator is decreasing, the grid's equivalent inertia is shrinking, and the rate of frequency change after frequency disturbances is increasing. Therefore, wind turbines are required to possess certain frequency support and inertia response capabilities.

[0003] Existing methods for doubly fed wind turbine inertia response mainly fall into the following two categories.

[0004] The first type involves adding an inertia control branch to a traditional grid-connected doubly-fed induction generator (DFIG). This method obtains the grid frequency through a phase-locked loop (PLL) or frequency measurement circuit, then differentiates or approximates the frequency deviation to generate an additional active power command based on the frequency change rate. The advantage of this method is that the inertia response can be adjusted by gain, making it easy to set the additional power according to grid connection specifications. However, this type of method relies on grid frequency detection and typically requires a PLL, frequency filtering, and frequency change rate calculation. Frequency differentiation can easily amplify measurement noise, and low-pass filtering must be added in engineering, resulting in a response delay. For rapidly changing frequency conditions, this delay weakens the support effect of the inertia response in the early stages of disturbances.

[0005] The second type is the grid-type doubly-fed induction generator (DFIG) wind turbine using Virtual Synchronous Machine (VSM) control. This method simulates the rotor motion equations of a synchronous machine, enabling the DFIG to generate an inertial response similar to that of a synchronous machine under frequency disturbances and power imbalance. This method does not require frequency differentiation through a phase-locked loop (PLL) to initiate inertial support, theoretically offering faster grid-based support capabilities. However, VSM control requires setting virtual inertia, damping coefficients, and power synchronization loop parameters; improper parameter tuning may introduce low-frequency oscillations. Furthermore, the DFIG machine-side converter cannot directly control the stator-side voltage and current. If the inner flux linkage or voltage control dynamics are slow, the inertial power command generated by the outer loop of the virtual synchronous machine is difficult to quickly translate into electromagnetic power output. In addition, the VSM damping term may introduce steady-state active power deviations when frequency deviations exist, requiring an additional power recovery stage.

[0006] Therefore, it is necessary to propose an inertia response control method suitable for grid-type DFIGs, so that on the one hand, it can utilize the fast active response capability of the grid control itself to generate active support without frequency detection delay in the early stage of frequency disturbance; on the other hand, it can adjust the amount of inertia injection like the additional inertia branch in the grid type, and avoid the outer power closed loop from immediately canceling the active support in the early stage of inertia response. Summary of the Invention

[0007] The present invention aims to at least partially solve one of the technical problems in the related art.

[0008] The main objective of this invention is to provide a method for controlling the inertia response of a grid-type doubly-fed generator.

[0009] The second objective of this invention is to provide an electronic device.

[0010] A third objective of this invention is to provide a non-transitory computer-readable storage medium.

[0011] To achieve the above objectives, a first aspect of the present invention provides a method for controlling the inertia response of a grid-connected doubly-fed generator, comprising: S1. Obtain the basic active power reference value, actual active power, reactive power reference value, and grid frequency of the doubly-fed induction generator; S2. Based on the power deviation between the basic active power reference value and the actual active power, an active power compensation amount is generated by an automatic active power regulator, and by setting the recovery time constant of the automatic active power regulator, the active power compensation amount is restored and adjusted according to the preset dynamic characteristics during the frequency disturbance process. S3. Generate a frequency change rate based on the power grid frequency, and generate an additional inertia power command through an automatic inertia response regulator. S4. Perform dead-zone processing on the power deviation, and adjust the integral input of the automatic active power regulator according to the power deviation after dead-zone processing, so as to avoid the active power compensation and the inertia support corresponding to the additional inertia power command being canceled by the automatic active power regulator. S5. Generate the active power reference value of the grid controller based on the basic active power reference value, the active power compensation amount, and the additional inertia power command, and control the doubly-fed induction generator to output active power based on the active power reference value.

[0012] Optionally, the automatic active power regulator adopts an integral regulation method, and its output active power compensation satisfies:

[0013] in: The power deviation between the baseline active power reference value and the actual active power; This refers to the recovery time constant of the automatic active power regulator; By adjusting the recovery time constant The recovery speed of the active power compensation amount is changed.

[0014] Optionally, the automatic inertia response regulator generates an additional inertia power command based on the grid frequency deviation, the additional inertia power command satisfying:

[0015] in: This refers to the power grid frequency deviation. This is the gain of the inertia response; The frequency change rate filter time constant; The time constant of the inertial response power element; By adjusting the inertia response gain Filtering time constant and the time constant of the power element in inertial response Adjust the response amplitude and dynamic characteristics of the additional inertia power command.

[0016] Optionally, the automatic active power regulator adopts a power dead-zone control method, and the integral input after dead-zone processing... satisfy: when: hour, ; when: hour, ; in: This is the preset power dead zone width.

[0017] Optionally, the active power reference value of the grid controller is obtained by the following formula:

[0018] in: Based on the reference value of active power; The active power compensation amount generated by the automatic active power regulator; Additional inertia power commands generated for the automatic inertia response regulator.

[0019] Optionally, the network controller employs a virtual flux linkage oscillator, which generates rotor flux linkage reference values ​​and synchronous phase angles based on the active power reference values ​​and reactive power reference values; and converts the rotor flux linkage reference values ​​into rotor current reference values ​​through a reference feedforward rotor flux linkage controller.

[0020] Optional, also includes: The additional inertia power command, the active power compensation amount, and the rotor current reference value are subjected to amplitude limiting processing; wherein, when the rotor current reference value exceeds the preset limit, the control amount corresponding to the reactive power support or voltage support is maintained first, and the control amount corresponding to the active inertia response is limited.

[0021] Optionally, the inertia response control method includes: First operating mode: Automatic inertia response regulator is turned off, and inertia response is formed only through the recovery time constant of automatic active power regulator; Second operating mode: Turn off the inertia function of the automatic active power regulator, and generate additional inertia power command through the automatic inertia response regulator; The third operating mode: Simultaneously activates the automatic active power regulator, the automatic inertia response regulator, and the power dead zone control to achieve coordinated control of the detection-delay inertia response and the adjustable inertia response.

[0022] To achieve the above objectives, a second aspect of this application provides an electronic device, including a processor and a memory; wherein the processor runs a program corresponding to the executable program code by reading executable program code stored in the memory, for implementing the method described in the first aspect embodiment.

[0023] To achieve the above objectives, a third aspect of this application provides a non-transitory computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the method described in the first aspect.

[0024] The embodiments of the present invention have the following beneficial effects: (1) Fast inertial response start-up. This invention utilizes the inherent active-frequency characteristics of the grid-type VFO to directly change the active power output of the doubly fed wind turbine in the early stage of grid frequency disturbance, without waiting for phase-locked loop frequency measurement, frequency change rate calculation and filtering. Therefore, it can realize an initial inertial response without detection delay.

[0025] (2) Adjustable inertia response. The present invention sets up an AIPR branch, and adjusts the amplitude and duration of the additional inertia power by adjusting the inertia response gain, the filtering time constant and the inertia response power link time constant, so as to meet the support requirements of different power grid frequencies.

[0026] (3) Power closed loop does not cancel inertia support. The present invention sets a dead zone in the APR power closed loop so that the active support within a certain range during frequency disturbance is not immediately eliminated by the APR integral element, thereby effectively combining VFO no-delay support with AIPR adjustable support.

[0027] (4) Applicable to DFIG network control structure. The active inertia command of the present invention is directly converted into the rotor current reference value through RRFFC, which can be executed quickly using the existing rotor current control loop of the machine-side converter without the need to add a complex flux observer or change the main circuit structure.

[0028] (5) Balancing short-term support and long-term power tracking. This invention provides short-term active power support during frequency disturbances and restores maximum power tracking or scheduled power tracking via APR after the disturbance ends, thus avoiding long-term power deviations from affecting the economical operation of the wind turbine. Attached Figure Description

[0029] The above-described and additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, in which: Appendix Figure 1 A flowchart illustrating an inertia response control method for a grid-type doubly-fed generator provided in an embodiment of the present invention; Appendix Figure 2 The overall structure for DFIG and VFO-RFRFC network control provided in the embodiments of the present invention; Appendix Figure 3 A VFO control principle diagram provided for an embodiment of the present invention; Appendix Figure 4 The RRFFC control principle diagram provided for embodiments of the present invention; Appendix Figure 5 The diagram below illustrates the APR power recovery control principle provided in this embodiment of the invention. Detailed Implementation

[0030] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] To address the technical problems existing in the prior art, this application provides a grid-type doubly-fed generator inertial response control method. This method is based on a Virtual Flux Oscillator (VFO) and a Reference-Feedforward Rotor Flux Controller (RFRFC), with an Automatic Power Regulator (APR) and an Automatic Inertial Response APR (AIPR) layered on top. A power dead zone is introduced in the APR power closed loop. The inherent active-frequency response of the VFO is preserved by delaying the APR time constant. An adjustable inertial injection is provided by adding a frequency change rate inertial branch to the AIPR. Furthermore, the APR power closed-loop dead zone prevents the APR integral stage from immediately canceling active power support in the early stages of the inertial response, thereby achieving an adjustable inertial response with no detection delay.

[0033] In this application, an inertia response control method for a grid-type doubly-fed induction generator (DFIG) is applied to a grid-type DFIG system. The DFIG system includes a doubly-fed induction generator, a rotor-side converter (RSC), a grid-side converter (GSC), a DC bus, a virtual flux oscillator (VFO), a reference-feedforward rotor flux controller (RFRFC), a rotor current controller, an APR (Active Flux Resonance Regulator), and an AIPR (Automatic Flux Resonance Regulator). This invention mainly focuses on the grid synchronization, active power reference generation, and rotor current reference generation parts before the current control of the rotor-side converter. The rotor current closed-loop and PWM or SVPWM modulation can use mature technologies, and this application does not specifically limit or elaborate on them.

[0034] The following describes, with reference to the accompanying drawings, an inertia response control method for a grid-type doubly-fed generator according to an embodiment of the present invention.

[0035] in: Appendix Figure 1 This is a flowchart illustrating an inertia response control method for a grid-type doubly-fed generator provided in an embodiment of the present invention.

[0036] Appendix Figure 2This diagram illustrates the overall structure of the DFIG and VFO-RFRFC network control system. It explains the overall connection relationships between the main circuit of the doubly-fed induction generator (DFIG), the turbine-side converter, the grid-side converter, the VFO, the rotor flux linkage controller, and the rotor current controller.

[0037] Appendix Figure 3 This is a diagram illustrating the VFO control principle. The diagram explains the control principle of the VFO, which generates the synchronization phase angle and flux linkage amplitude based on active power reference, reactive power reference, actual active / reactive power, and flux linkage amplitude.

[0038] Appendix Figure 4 This is the RRFFC control principle diagram. Only the RRFFC section is retained in this diagram to illustrate how the active power reference and reactive power reference directly generate the rotor current reference value.

[0039] Appendix Figure 5 This is a schematic diagram of the APR power recovery control principle. The diagram illustrates the relationship between the base active power reference, actual active power feedback, the APR integral recovery channel, and the enable logic.

[0040] The main symbols of this invention are explained below: Electrical quantity symbols: Stator voltage, For stator current, For rotor voltage, For rotor current, This is the reference value for rotor voltage. This is the reference value for rotor current. , These are the d-axis and q-axis components of the stator current, respectively. , These are the reference values ​​for the rotor current along the d-axis and q-axis, respectively. This is the grid voltage. For grid-connected current, For the equivalent grid impedance, This refers to the grid-side converter voltage. This refers to the grid-side converter current. For rotor flux linkage, The rotor flux reference value generated for VFO, This represents the flux linkage amplitude. This is a reference value for flux linkage amplitude. This is the q-axis reference component of the rotor flux linkage; For magnetizing inductance, This is the rotor inductance.

[0041] Power and frequency symbols: This refers to the total active power of the doubly-fed wind turbine. The reference value for basic active power is shown in the attached figure. This can be understood as a basic active power reference or an active power reference after scheduling / maximum power point tracking. For power grid dispatching commands, This is the maximum power tracking command for the wind turbine main control. Active power calculated for VFO Reactive power calculated for VFO The active power reference value used for VFO. This is the initial active power reference value for the VFO. This is a reference value for reactive power. For the power grid frequency, For the rated frequency, θ represents the grid frequency deviation; θ is the VFO output phase angle. The rated angular frequency, The synchronization angular frequency, ω is the rotor angular velocity.

[0042] Control and limiting symbols: α is the active-phase synchronization gain of VFO, α is the reactive-flux amplitude adjustment gain of VFO, and EN is the APR enable signal. This is the active power compensation amount output by APR. Additional inertia power command output by AIPR. The error between the baseline active power reference value and the actual active power. The integral input after APR power closed-loop dead-time processing; The APR time constant, The time constant of the AIPR inertial response power element. The frequency change rate filter time constant, For inertial response gain, APR power closed-loop dead zone width The additional inertia power limit value is given, s is the Laplace operator, and sign(·) is the sign function.

[0043] like Figure 1 As shown, the method includes the following steps: S1. Obtain the basic active power reference value, actual active power, reactive power reference value, and grid frequency of the doubly-fed induction generator.

[0044] Specifically, the baseline active power reference value is used to characterize the target active power output value of the doubly-fed induction generator under normal operating conditions, while the actual active power reflects the current actual active power output of the doubly-fed induction generator. By collecting the baseline active power reference value and the actual active power, the power deviation signal required by the subsequent automatic active power regulator is obtained. Simultaneously, the grid frequency is acquired to determine the grid frequency disturbance state and provide frequency change information to the automatic inertia response regulator; the reactive power reference value is acquired to maintain voltage and flux regulation requirements during grid control.

[0045] S2. Based on the power deviation between the basic active power reference value and the actual active power, an active power compensation amount is generated by an automatic active power regulator, and by setting the recovery time constant of the automatic active power regulator, the active power compensation amount is restored and adjusted according to the preset dynamic characteristics during frequency disturbance.

[0046] Specifically, the power deviation is obtained based on the difference between the baseline active power reference value and the actual active power. This power deviation is input into the automatic active power regulator, which generates an active power compensation amount through integral adjustment. The automatic active power regulator is equipped with a recovery time constant to regulate the rate of change of the active power compensation amount. When a frequency disturbance occurs in the power grid, the recovery time constant is increased to maintain the output of the active power compensation amount for a certain period of time in the initial stage of the disturbance, thereby preserving the active power response generated by the grid controller itself. After the frequency disturbance ends, the automatic active power regulator gradually restores the actual active power to the operating state corresponding to the baseline active power reference value.

[0047] S3. Generate a frequency change rate based on the power grid frequency, and generate an additional inertia power command through an automatic inertia response regulator.

[0048] Specifically, the frequency change rate is calculated based on the deviation between the real-time collected grid frequency and the rated frequency, and a filtering stage is used to reduce the impact of frequency measurement noise on the control process. Subsequently, the processed frequency change rate is input to the automatic inertia response regulator, which generates an additional inertia power command based on the inertia response gain, filtering time constant, and inertia response time constant. Specifically, when the grid frequency decreases, the additional inertia power command is used to increase the active power output of the doubly-fed induction generator; when the grid frequency increases, the additional inertia power command is used to decrease the active power output of the doubly-fed induction generator, thereby providing power support similar to the inertia response characteristics of a synchronous machine.

[0049] S4. Perform dead-zone processing on the power deviation, and adjust the integral input of the automatic active power regulator according to the power deviation after dead-zone processing, so as to avoid the active power compensation and the inertia support corresponding to the additional inertia power command being canceled by the automatic active power regulator.

[0050] Specifically, a preset power dead zone is set in the power closed loop of the automatic active power regulator to judge the power deviation between the reference value of basic active power and the actual active power. When the power deviation is within the preset dead zone range, the integral input of the automatic active power regulator is set to zero, so that the automatic active power regulator does not temporarily perform recovery adjustment on the active power changes generated during frequency disturbances; when the power deviation exceeds the preset dead zone range, the deviation amount after exceeding the dead zone is re-inputted into the automatic active power regulator for integral adjustment. Through the above dead zone control method, a coordinated control relationship is formed between the automatic active power regulator and the automatic inertia response regulator, avoiding the active power support during the inertia response process being quickly offset by the power recovery link.

[0051] S5. Generate the active power reference value of the grid controller based on the basic active power reference value, the active power compensation amount, and the additional inertia power command, and control the doubly-fed induction generator to output active power based on the active power reference value.

[0052] Specifically, the basic active power reference value, the active power compensation amount generated by the automatic active power regulator, and the additional inertia power command generated by the automatic inertia response regulator are combined to form the active power reference value of the grid controller. This active power reference value is input into the grid control loop to generate corresponding synchronization control quantities and electromagnetic power adjustment commands. Furthermore, it controls the rotor current of the doubly-fed induction generator through the generator-side converter, achieving rapid adjustment of the electromagnetic power output. Through this control process, the doubly-fed induction generator simultaneously possesses rapid inertia response capability in the initial stage of disturbance and subsequent power recovery capability.

[0053] Specifically, a grid-connected doubly-fed generator inertia response control method is implemented through the following steps: (1) Existing DFIG basic control structure.

[0054] Specifically, this invention is based on a previously applied grid-type DFIG control scheme. This basic scheme uses a VFO to generate a rotor flux linkage reference value. and synchronous phase angle This allows the DFIG to establish a synchronous coordinate system without relying on a phase-locked loop; simultaneously, RFRFC is used to quickly convert the VFO active and reactive power references into rotor current reference values, enabling changes in active power references to be rapidly reflected in the electromagnetic power output of the doubly-fed induction generator (DFIG) via the machine-side converter. The aforementioned VFO synchronous control and RFRFC rapid power regulation are not the focus of this application's repeated protection; this application only utilizes them as the basis for inertial response execution. For this invention, it is only necessary to convert the basic active power reference value... The additional active power generated by APR / AIPR is uniformly superimposed into the VFO active power reference. Then it can be executed by RFRFC and rotor current controller.

[0055] (2) Use the APR time constant delay to form an equivalent inertial response without detection delay.

[0056] In one embodiment of the present invention, an equivalent inertial response without detection delay is formed using an APR time constant delay. Specifically, this application sets an APR outside the basic grid control layer to eliminate the total active power of the doubly-fed wind turbine. Compared with the basic active power reference The steady-state error between them. APR can be achieved using an integral controller, whose output is... The control form can be written as:

[0057]

[0058] in This is the APR time constant. The APR output is superimposed onto the VFO active reference.

[0059] When the grid frequency decreases, the VFO, due to its inherent active-frequency characteristics, will rapidly increase the active power output of the doubly-fed induction generator (DFIG); when the grid frequency increases, the VFO will rapidly decrease the active power output. The APR (Active Power Response) then... Gradually Restore to Since the active power change in the initial stage of frequency disturbance is generated by the network-type VFO itself, it is not necessary to detect the rate of frequency change first, nor is it necessary to go through phase-locked loop, filtering and differentiation. Therefore, the equivalent inertial response has the characteristic of no detection delay.

[0060] It should be noted that, The larger the value, the slower the APR recovery, the longer the active offset during frequency changes, and the more obvious the equivalent inertia support. The smaller the value, the faster the APR recovery, the faster the active power offset is eliminated, and the weaker the equivalent inertia support. In one possible example, A time interval of 0.5s to 2s can be used to form a significant inertia-like response; when it is necessary to weaken this response, the time interval can be adjusted accordingly. The time is reduced to approximately 0.05 seconds. The actual value is determined based on the wind turbine's mechanical energy storage, the converter's current margin, the grid frequency support requirements, and the power point tracking speed requirements.

[0061] (3) Set up an AIPR inertia response branch to achieve adjustable inertia injection.

[0062] In one embodiment of the invention, an AIPR inertial response branch is configured to achieve adjustable inertial injection. Specifically, to further provide an adjustable inertial response based on the equivalent inertial response without detection delay, the invention incorporates an AIPR. The AIPR detects the grid frequency. Relative to rated frequency The deviation is calculated, and an additional inertia power command is generated through the frequency change rate branch. :

[0063]

[0064] in For inertial response gain, The frequency change rate filter time constant, This represents the time constant of the AIPR inertial response power element. The negative sign before the symbol ensures that when the grid frequency decreases and the rate of frequency change is negative, ... This is an instruction to increase active power output; when the grid frequency rises and the rate of frequency change is positive, Instructions to reduce active power output.

[0065] AIPR branch output is superimposed onto the VFO active reference:

[0066] By adjusting The amplitude of the inertial response can be changed by adjusting... A trade-off can be made between frequency change rate noise suppression and response speed, by... Setting it to a smaller value can simulate the rapid active power regulation characteristics of a grid-connected doubly-fed induction generator (DFIG), allowing the additional inertia power command to be applied to the RFRFC and rotor current controller more quickly. In one possible embodiment, The value can be between 0.01s and 0.1s. A value of 0.02 s to 0.2 s can be used. The inertia support power and converter current margin are determined according to the grid connection specifications.

[0067] Since AIPR needs to detect the grid frequency and calculate the rate of frequency change, its response inevitably involves measurement, filtering, and calculation delays. Therefore, AIPR is mainly used to provide an adjustable inertial response, while the fastest active power support in the early stages of frequency disturbances is formed by the VFO and APR delay.

[0068] (4) Set a dead zone in the APR power closed loop to achieve coordination between zero-delay response and adjustable response.

[0069] If APR directly addresses and Integrating the error between the two, the active power support generated by the inherent active-frequency characteristics of the VFO and the inertial power injected by AIPR may be quickly canceled out by APR, resulting in a decrease in the amplitude of the inertial response. To solve this problem, this invention sets a dead zone in the APR power closed loop. APR points input Defined as:

[0070]

[0071] in , It is a symbolic function. The APR output satisfies:

[0072] With the aforementioned dead zone setting, when frequency disturbances cause the doubly fed induction generator (DFIG) to generate active inertia support within a certain amplitude, the Active Power Regulator (APR) will not perform integral correction on the active power deviation, thus preserving the VFO's (Voltage-Free Active Power Support) and the AIPR's (Adjustable Inertia Injection) canal. When the active power deviation exceeds the dead zone or the frequency disturbance ends, the APR will gradually restore power tracking to ensure that the unit meets the maximum power tracking or dispatch power requirements during long-term operation.

[0073] What is understandable is that It can be determined based on the unit's rated power, allowable short-time active power offset, and current limiting margin. In one test example, The allowable value is 0.01 pu to 0.10 pu. When stronger inertia support is required, the value can be increased appropriately. or increase When more stringent power point tracking is required, the power consumption can be appropriately reduced. or reduce .

[0074] (5) Coordination between limiting the field of view and protecting the field of view.

[0075] To avoid inertial response causing rotor current, stator current, or converter capacity to exceed limits, this invention addresses... The final rotor current reference value is set with a limit. The additional inertial power can meet the following requirements:

[0076] in The parameters are determined based on the rotor current margin, the releaseable mechanical energy of the wind turbine, and grid connection specifications. When the rotor current reference value exceeds the current limit, priority is given to maintaining the reactive or voltage support components, and then the active inertia support components are reduced. Under conditions such as low voltage ride-through, high voltage ride-through, or DC bus abnormalities, the AIPR output can be blocked or reduced by the protection logic, while retaining the basic grid control and necessary current limiting functions.

[0077] Ultimately, this invention can be implemented in the following three modes.

[0078] The first method is the APR equivalent inertia method. In this case, AIPR is not enabled, and only the APR time constant is set. This enables the network-type DFIG to generate inertial-like active support without detection delay during frequency disturbances, relying on the inherent active-frequency characteristics of the VFO.

[0079] The second method is the AIPR explicit inertia approach. In this case, the AIPR time constant is... Reduce the frequency and generate additional inertia power command through frequency change rate detection. Inertial response quantity is Adjustment. This method allows for adjustable response, but it introduces frequency measurement and filtering delays.

[0080] The third method is the APR dead-zone coordination method. In this method, APR, AIPR, and the APR power closed-loop dead zone are activated simultaneously. VFO and APR delays provide active power support with no detection delay in the early stages of disturbances, AIPR provides adjustable additional inertial power, and the APR dead zone prevents the above support from being quickly canceled out by the outer loop. This method has both no-delay initial response and adjustable inertial injection capability, and is the preferred embodiment of the present invention.

[0081] To implement the methods of the above embodiments, the present invention also provides an electronic device, which includes a memory and a processor; wherein the processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the various steps of the methods described above.

[0082] To implement the above embodiments, this application also proposes a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the method described in the foregoing embodiments.

[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0084] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0085] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A method for controlling the inertia response of a grid-connected doubly-fed generator, characterized in that, Applied to grid-connected doubly-fed induction generator systems, the following steps are included: S1. Obtain the basic active power reference value, actual active power, reactive power reference value, and grid frequency of the doubly-fed induction generator; S2. Based on the power deviation between the basic active power reference value and the actual active power, an active power compensation amount is generated by an automatic active power regulator, and by setting the recovery time constant of the automatic active power regulator, the active power compensation amount is restored and adjusted according to the preset dynamic characteristics during the frequency disturbance process. S3. Generate a frequency change rate based on the power grid frequency, and generate an additional inertia power command through an automatic inertia response regulator. S4. Perform dead-zone processing on the power deviation, and adjust the integral input of the automatic active power regulator according to the power deviation after dead-zone processing, so as to avoid the active power compensation and the inertia support corresponding to the additional inertia power command being canceled by the automatic active power regulator. S5. Generate the active power reference value of the grid controller based on the basic active power reference value, the active power compensation amount, and the additional inertia power command, and control the doubly-fed induction generator to output active power based on the active power reference value.

2. The inertia response control method for a grid-type doubly-fed generator according to claim 1, characterized in that, The automatic active power regulator adopts integral regulation, and its output active power compensation satisfies the following: in: The power deviation between the baseline active power reference value and the actual active power; This refers to the recovery time constant of the automatic active power regulator; By adjusting the recovery time constant The recovery speed of the active power compensation amount is changed.

3. The inertia response control method for a grid-type doubly-fed generator according to claim 2, characterized in that, The automatic inertia response regulator generates an additional inertia power command based on the grid frequency deviation, and the additional inertia power command satisfies: in: This refers to the power grid frequency deviation. This is the gain of the inertia response; The frequency change rate filter time constant; The time constant of the inertial response power element; By adjusting the inertia response gain Filtering time constant and the time constant of the inertial response power element Adjust the response amplitude and dynamic characteristics of the additional inertia power command.

4. The inertia response control method for a grid-type doubly-fed generator according to claim 3, characterized in that, The automatic active power regulator employs a power dead-zone control method, wherein the integral input after dead-zone processing... satisfy: when: hour, ; when: hour, ; in: This is the preset power dead zone width.

5. The inertia response control method for a grid-type doubly-fed generator according to claim 4, characterized in that, The active power reference value of the grid controller is obtained by the following formula: in: Based on the reference value of active power; The active power compensation amount generated by the automatic active power regulator; Additional inertia power commands generated for the automatic inertia response regulator.

6. The inertia response control method for a grid-type doubly-fed generator according to claim 5, characterized in that, The network controller employs a virtual flux linkage oscillator, which generates rotor flux linkage reference values ​​and synchronous phase angles based on the active power reference values ​​and reactive power reference values; and converts the rotor flux linkage reference values ​​into rotor current reference values ​​through a reference feedforward rotor flux linkage controller.

7. The inertia response control method for a grid-type doubly-fed generator according to claim 6, characterized in that, Also includes: The additional inertia power command, the active power compensation amount, and the rotor current reference value are subjected to amplitude limiting processing; wherein, when the rotor current reference value exceeds the preset limit, the control amount corresponding to the reactive power support or voltage support is maintained first, and the control amount corresponding to the active inertia response is limited.

8. The inertia response control method for a grid-type doubly-fed generator according to claim 7, characterized in that, The inertia response control method includes: First operating mode: Automatic inertia response regulator is turned off, and inertia response is formed only through the recovery time constant of automatic active power regulator; Second operating mode: Turn off the inertia function of the automatic active power regulator, and generate additional inertia power command through the automatic inertia response regulator; The third operating mode: Simultaneously activates the automatic active power regulator, the automatic inertia response regulator, and the power dead zone control to achieve coordinated control of the detection-delay inertia response and the adjustable inertia response.

9. An electronic device, characterized in that, Including processor and memory; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the method as described in any one of claims 1-6.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-6.

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