Converter fault ride-through control delay compensation method and device

Abstract

The invention relates to the technical field of power system control, in particular to a converter fault ride-through control delay compensation method and device.The method comprises the steps that the response speed of a reactive current instruction of converter equipment is detected so as to estimate control delay time, and when the voltage is smaller than a certain threshold value, the control delay time is calculated; and predicting a voltage estimation value after the control delay time, and calculating a reactive current instruction according to the voltage estimation value so as to control the converter equipment to emit reactive power under the condition that the voltage estimation value is smaller than the first voltage and absorb the first reactive current under the condition that the voltage estimation value is larger than the first voltage until the first reactive current is equal to the first voltage. Therefore, the problem that the voltage fluctuation suppression effect is poor due to the fact that the time sequence synchronization of the voltage and the reactive current instruction cannot be guaranteed due to lack of a control delay compensation strategy in the prior art is solved.

Description

Technical Field

[0001] The present application relates to the field of power system control technology, and in particular to a method and device for compensating for converter fault ride-through control delay. Background Art

[0002] In related technologies, during high-voltage direct current transmission, if the direct current fails to commutate or fails to lock, it is easy to cause the voltage at the inverter end of the new energy power generation equipment to be too low. At this time, the equipment needs to enter the low voltage ride-through mode and inject reactive current into the system to help the voltage recover.

[0003] However, in the related technology, there is a delay in low voltage ride-through control, and reactive power generation cannot be stopped immediately when the voltage recovers, causing reactive power surplus and transient voltage reversal. There is a lack of control delay compensation strategy, and the synchronization of voltage and reactive current command timing cannot be guaranteed. The effect of suppressing voltage fluctuations is poor, which urgently needs to be improved. Summary of the invention

[0004] The present application provides a method and device for compensating for control delay of a converter fault ride-through, so as to solve the problem in the related art that, due to the lack of control delay compensation strategy, the voltage and reactive current command timing cannot be synchronized, resulting in poor voltage fluctuation suppression effect.

[0005] The first aspect of the present application provides a method for compensating for control delay of a converter fault ride-through, comprising the following steps: detecting the response speed of a reactive current command of a converter device to estimate the control delay time; predicting a voltage estimation value after the control delay time when the voltage is less than a preset threshold; calculating a reactive current command based on the voltage estimation value to control the converter device to emit reactive power when the voltage estimation value is less than a first preset voltage, and to absorb a first reactive current when the voltage estimation value is greater than the first preset voltage, until the voltage estimation value is equal to the first preset voltage.

[0006] Through the above technical scheme, the embodiment of the present application can estimate the control delay time by detecting the response speed of the reactive current instruction of the converter device, which is helpful to accurately grasp the parameters related to the working state of the converter. When the voltage is less than a certain threshold, the voltage estimation value after the control delay time is predicted, and the voltage situation can be predicted in advance. Then, the reactive current instruction is calculated according to the voltage estimation value, so that when the voltage estimation value is less than the first voltage, the converter device is controlled to emit reactive power, and when it is greater than the first voltage, the first reactive current is absorbed. The way of flexibly adjusting the reactive current according to different voltage conditions is conducive to improving the stability of transient voltage, and can more effectively deal with the situation of converter fault crossing, and optimize the operating performance of the converter under different voltage conditions.

[0007] Optionally, in one embodiment of the present application, the calculation formula of the reactive current command is:

[0008] I q,ref = k*(1-U pre ),

[0009] Among them, k is the reactive current coefficient, which is generally required to be higher than 1.5, U pre is the predicted voltage value.

[0010] Through the above technical scheme, the embodiment of the present application can make the reactive current command flexibly adjusted according to the recovery value of the machine-end voltage, which helps to accurately determine the reactive current command according to the voltage conditions of the system, and then effectively control the reactive output or absorption of the converter to adapt to different operating requirements.

[0011] Optionally, in one embodiment of the present application, after predicting the voltage estimation value after the control delay time, it also includes: judging that the voltage estimation value is less than a second preset voltage; if the voltage estimation value is less than the second preset voltage, starting to output a second reactive current.

[0012] Through the above technical solution, the embodiment of the present application can further refine the response strategy for voltage conditions, and distinguish different degrees of low voltage conditions by setting the second voltage. When the voltage is at a lower level, the second reactive current is output in time. The hierarchical reactive current output strategy helps to more accurately adjust the reactive power of the system, enhance the control ability of voltage stability, and more effectively avoid the occurrence of unstable conditions such as voltage collapse in the process of responding to converter fault ride-through, thereby improving the adaptability and reliability of the entire system under complex working conditions.

[0013] Optionally, in one embodiment of the present application, before starting to output the second reactive current, it also includes: identifying a current voltage trend of the voltage; and allowing the second reactive current to be output when the current voltage trend is a downward trend.

[0014] Through the above-mentioned technical scheme, the embodiment of the present application can identify the current voltage trend of the voltage before starting to output the second reactive current, and only allow the second reactive current to be output when the current voltage trend is a downward trend. It takes into account the dynamic change trend of the voltage, not just the current value of the voltage, and can avoid unnecessary output of the second reactive current when the voltage may only fluctuate briefly and is not actually in a downward trend. It can more accurately control the output of the reactive current according to the actual trend of the voltage, which helps to improve the effectiveness and pertinence of the reactive current output, thereby better maintaining transient voltage stability, optimizing the performance of the converter during fault ride-through, and improving the ability of the entire system to cope with voltage fluctuations.

[0015] Optionally, in one embodiment of the present application, the second preset voltage is less than the first preset voltage.

[0016] Through the above technical solution, the embodiment of the present application can adopt different response strategies for different degrees of voltage drops, making the system more flexible and accurate in responding to voltage changes.

[0017] The second aspect of the present application provides a converter fault ride-through control delay compensation device, including: a detection module, used to detect the response speed of the converter device reactive current command to estimate the control delay time; a prediction module, used to predict the voltage estimation value after the control delay time when the voltage is less than a preset threshold; a compensation module, used to calculate the reactive current command according to the voltage estimation value, so as to control the converter device to emit reactive power when the voltage estimation value is less than a first preset voltage, and to absorb a first reactive current when the voltage estimation value is greater than the first preset voltage, until the voltage estimation value is equal to the first preset voltage.

[0018] Through the above technical scheme, the embodiment of the present application can estimate the control delay time by detecting the response speed of the reactive current instruction of the converter device, which is helpful to accurately grasp the parameters related to the working state of the converter. When the voltage is less than a certain threshold, the voltage estimation value after the control delay time is predicted, and the voltage situation can be predicted in advance. Then, the reactive current instruction is calculated according to the voltage estimation value, so that when the voltage estimation value is less than the first voltage, the converter device is controlled to emit reactive power, and when it is greater than the first voltage, the first reactive current is absorbed. The way of flexibly adjusting the reactive current according to different voltage conditions is conducive to improving the stability of transient voltage, and can more effectively deal with the situation of converter fault crossing, and optimize the operating performance of the converter under different voltage conditions.

[0019] Optionally, in one embodiment of the present application, the calculation formula of the reactive current command is:

[0020] I q,ref = k*(1-U pre ),

[0021] Among them, k is the reactive current coefficient, which is generally required to be higher than 1.5, U pre is the predicted voltage value.

[0022] Through the above technical scheme, the embodiment of the present application can make the reactive current command flexibly adjusted according to the recovery value of the machine-end voltage, which helps to accurately determine the reactive current command according to the voltage conditions of the system, and then effectively control the reactive output or absorption of the converter to adapt to different operating requirements.

[0023] Optionally, in one embodiment of the present application, the compensation module includes: a first judgment unit, used to judge that the voltage estimation value is less than a second preset voltage; and an output unit, used to start outputting a second reactive current when the voltage estimation value is less than the second preset voltage.

[0024] Through the above technical solution, the embodiment of the present application can further refine the response strategy for voltage conditions, and distinguish different degrees of low voltage conditions by setting the second voltage. When the voltage is at a lower level, the second reactive current is output in time. The hierarchical reactive current output strategy helps to more accurately adjust the reactive power of the system, enhance the control ability of voltage stability, and more effectively avoid the occurrence of unstable conditions such as voltage collapse in the process of responding to converter fault ride-through, thereby improving the adaptability and reliability of the entire system under complex working conditions.

[0025] Optionally, in one embodiment of the present application, the compensation module includes: an identification unit, used to identify the current voltage trend of the voltage; and a second judgment unit, used to allow the output of the second reactive current when the current voltage trend is a downward trend.

[0026] Through the above-mentioned technical scheme, the embodiment of the present application can identify the current voltage trend of the voltage before starting to output the second reactive current, and only allow the second reactive current to be output when the current voltage trend is a downward trend. It takes into account the dynamic change trend of the voltage, not just the current value of the voltage, and can avoid unnecessary output of the second reactive current when the voltage may only fluctuate briefly and is not actually in a downward trend. It can more accurately control the output of the reactive current according to the actual trend of the voltage, which helps to improve the effectiveness and pertinence of the reactive current output, thereby better maintaining transient voltage stability, optimizing the performance of the converter during fault ride-through, and improving the ability of the entire system to cope with voltage fluctuations.

[0027] Optionally, in one embodiment of the present application, the second preset voltage is less than the first preset voltage.

[0028] Through the above technical solution, the embodiment of the present application can adopt different response strategies for different degrees of voltage drops, making the system more flexible and accurate in responding to voltage changes.

[0029] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the converter fault ride-through control delay compensation method as described in the above embodiment.

[0030] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned converter fault ride-through control delay compensation method.

[0031] The fifth aspect of the present application provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned converter fault ride-through control delay compensation method.

[0032] In the embodiment of the present application, the control delay time can be estimated by detecting the reactive current command response speed, and the parameters related to the working state of the converter can be grasped; when the voltage is less than the threshold, the voltage estimation value after the control delay is predicted to predict the voltage situation, and then the reactive current command is calculated based on this, and the reactive current is flexibly adjusted according to the voltage size, so as to improve the transient voltage stability and the ability to cope with fault ride-through, and optimize the performance of the converter under different voltage states; the reactive current command can be flexibly adjusted according to the terminal voltage recovery value, and the reactive current command can be accurately determined to effectively control the reactive output or absorption of the converter to meet different needs; the second voltage is set to refine the voltage response strategy, output reactive current in stages, accurately adjust reactive power, enhance voltage stability control capability, avoid voltage collapse during fault ride-through, and improve the adaptability and reliability of the system to complex working conditions; before outputting the second reactive current, the voltage trend is identified, and it is output only when the trend is downward, avoiding unnecessary output, improving the effectiveness and pertinence of reactive current output, maintaining transient voltage stability, optimizing fault ride-through performance, and improving the ability to cope with voltage fluctuations; different strategies are adopted for different voltage drop degrees, so that the system can respond to voltage changes more flexibly and accurately.

[0033] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0035] Figure 1 A flowchart of a method for compensating for a converter fault ride-through control delay provided according to an embodiment of the present application;

[0036] Figure 2 It is a flow chart of a method for compensating a converter fault ride-through control delay according to a specific embodiment of the present application;

[0037] Figure 3 A schematic diagram of the structure of a converter fault ride-through control delay compensation device provided according to an embodiment of the present application;

[0038] Figure 4The figure is a structural example diagram of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0039] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0040] The following describes the converter fault ride-through control delay compensation method and device of the embodiment of the present application with reference to the accompanying drawings. In view of the related technology mentioned in the above background technology center, due to the lack of control delay compensation strategy, the voltage and reactive current command timing synchronization cannot be guaranteed, resulting in poor suppression of voltage fluctuations. The present application provides a converter fault ride-through control delay compensation method, in which the control delay time can be estimated by detecting the response speed of the reactive current command of the converter device, which helps to accurately grasp the working state related parameters of the converter. When the voltage is less than a certain threshold, the voltage estimation value after the control delay time is predicted, and the voltage situation can be predicted in advance. Then, the reactive current command is calculated according to the voltage estimation value, so that when the voltage estimation value is less than the first voltage, the converter device is controlled to emit reactive power, and when it is greater than the first voltage, the first reactive current is absorbed. The way of flexibly adjusting the reactive current according to different voltage conditions is conducive to improving the stability of transient voltage, and can more effectively deal with the situation of converter fault ride-through, and optimize the operating performance of the converter under different voltage conditions. Thereby, the problem in the related art that, due to the lack of a control delay compensation strategy, the timing synchronization of the voltage and reactive current instructions cannot be guaranteed, resulting in poor voltage fluctuation suppression effect is solved.

[0041] Specifically, Figure 1 A flow chart of a method for compensating a converter fault ride-through control delay provided in an embodiment of the present application.

[0042] like Figure 1 As shown, the converter fault ride-through control delay compensation method includes the following steps:

[0043] In step S101, the response speed of the reactive current instruction of the converter device is detected to estimate the control delay time.

[0044] It can be understood that the reactive current command is a control signal about the size and direction of reactive current sent by the control system to the converter according to the operating status and needs of the power grid. It guides the converter to generate or absorb reactive current, thereby adjusting the reactive power balance of the power grid and maintaining the stability of the power grid voltage. For example, when the power grid voltage drops, the converter outputs reactive current to support the power grid voltage by issuing appropriate reactive current commands. The control delay time refers to the time taken from the generation of reactive current commands, through signal transmission, processing and other links, until the command actually starts to take effect inside the converter and affects its reactive current output.

[0045] In the actual implementation process, the converter equipment is the key hub for power conversion and control, and its reactive current instruction response characteristics are crucial to maintaining the stability of the power system. Specifically, when the converter equipment receives the reactive current instruction, it is necessary to accurately monitor the changes in the actual reactive current output of the converter equipment to evaluate its response speed to the instruction. This response speed is usually quantified by measuring the time from the time the instruction is issued to the time when the converter output reactive current reaches or approaches a specific proportion of the value required by the instruction (for example, 90% or 95%, etc.). By accurately detecting the response speed of the reactive current instruction of the converter equipment, the control delay time T can be further estimated. d . Accurately estimate the control delay time T d , which provides a key basis for the subsequent implementation of effective control strategies, and helps to better coordinate the output timing of reactive current with the dynamic changes of grid voltage in key scenarios such as converter fault ride-through, thereby avoiding adverse phenomena such as transient voltage reversal caused by untimely control, and ensuring that the power system can maintain a stable and reliable operation state under various working conditions.

[0046] The embodiment of the present application can estimate the control delay time by detecting the response speed of the reactive current instruction of the converter device, closely combining the actual operating characteristics of the converter, and taking into account the working conditions of the converter itself, so that the estimated control delay time is more accurate. Accurate control delay time estimation helps to formulate more reasonable control strategies. In the operation of the power system, it can effectively adjust the reactive current, thereby enhancing the system stability, improving the converter's ability to cope with fault crossing, avoiding adverse effects such as voltage fluctuations caused by inaccurate control delay estimation, and optimizing the operating efficiency of the entire power system.

[0047] In step S102, when the voltage is less than a preset threshold, a voltage estimation value after a control delay time is predicted.

[0048] It is understood that the preset threshold is obtained based on, but not limited to, experimental results or theoretical analysis, and the preset threshold of the terminal voltage in the embodiment of the present application is 0.95pu. The voltage estimation value refers to the result obtained by estimating the voltage value at a certain moment in the future (i.e., the moment after the control delay time) through a specific prediction method. It is not the actual voltage value directly measured, but an estimated voltage value calculated based on historical data, current system status and prediction model.

[0049] In some cases, when the terminal voltage drops from the rated value to 0.95pu, the neural network model is used to predict the voltage recovery form. Assume that the fault ride-through control period is T c , after the control delay T has been estimated d Under the premise (T c <<T d ), we can know the reactive current command I at any time qrer , all passing through T d After that, the execution starts, and its duration is T c Based on historical data, we can estimate I qrer The quantitative relationship between the voltage recovery rate and the voltage recovery rate is established by using a neural network. The voltage recovery rate can be obtained from the T c The voltage change in a time period is related to T c The ratio is worth getting.

[0050] Furthermore, at a certain time t1, in order to predict t1+T d The voltage value at the moment t1+kT should be determined first. c (k=1,2,3...) corresponding to I qref , that is, t1+kT c I starts to take effect at any time qref At t1+kT c -T d The corresponding I qrer Substitute it into the neural network model to estimate the voltage recovery rate, so that t1+(k-1)T can be estimated c to t1+kT c The voltage recovery amount within the time period. By predicting section by section, when k = T d / T c Completed at t1+T d Voltage prediction at time t1+T d The predicted voltage value is defined as U pre .

[0051] The embodiment of the present application can predict the voltage estimate value after the control delay time when the voltage is less than a certain threshold, and can provide forward-looking information for the power system, which helps to plan countermeasures in advance at the early stage of voltage drop, such as adjusting the reactive power compensation device in advance, etc., to avoid further deterioration of voltage and cause greater impact on power equipment and system stability.

[0052] In step S103, a reactive current instruction is calculated based on the voltage estimation value to control the converter device to generate reactive power when the voltage estimation value is less than the first preset voltage, and to absorb a first reactive current when the voltage estimation value is greater than the first preset voltage, until the voltage estimation value is equal to the first preset voltage.

[0053] It is understandable that the first preset voltage can be obtained based on, including but not limited to, experimental results or theoretical analysis. In the embodiment of the present application, the first preset voltage value is 1 p.u. When the voltage estimation value is compared with the voltage, the control action of the converter is determined. If the estimated value is less than it, the converter emits reactive current to support the grid voltage; if it is greater than it, the converter absorbs reactive current to prevent the voltage from being too high, ensuring that the grid voltage fluctuates within a reasonable range.

[0054] Optionally, in one embodiment of the present application, the calculation formula of the reactive current command is:

[0055] I q，ref = k*(1-U pre ),

[0056] Among them, k is the reactive current coefficient, which is generally required to be higher than 1.5, U pre is the voltage prediction value. At this time, the reactive current value is calculated by the predicted voltage, thereby compensating the influence of the control delay on the low voltage ride through control strategy.

[0057] In the actual implementation process, when U pre When <1p.u., U pre Substitute the above formula to calculate the reactive current command. At this time, the converter outputs reactive current. pre >1p.u., U pre Substitute the above formula to calculate the reactive current command. At this time, the converter absorbs reactive current.

[0058] Optionally, in one embodiment of the present application, after predicting the voltage estimation value after the control delay time, it also includes: judging that the voltage estimation value is less than a second preset voltage; if the voltage estimation value is less than the second preset voltage, starting to output a second reactive current.

[0059] Specifically, the second preset voltage is less than the first preset voltage. The second preset voltage is obtained based on, but not limited to, experimental results or theoretical analysis. In the embodiment of the present application, the second preset voltage is 0.9 pu.

[0060] In some embodiments, before starting to output the second reactive current, the method further includes: identifying a current voltage trend of the voltage; and allowing the second reactive current to be output when the current voltage trend is a downward trend. pre When the value is less than 0.9pu and is on a downward trend, it starts to output reactive current.

[0061] The embodiment of the present application can realize intelligent control of reactive power of the converter device by calculating reactive current instructions according to the voltage estimation value. When the voltage estimation value is less than the first voltage, the converter device is controlled to emit reactive power, which can respond to low voltage conditions in a timely manner, increase system voltage, and enhance the stability of the power system; and when the voltage estimation value is less than the first voltage, the first reactive current is absorbed. This strategy of flexible switching according to voltage conditions helps to maintain the balance of reactive power in the power system, optimize the operating efficiency of the power system, and effectively avoid voltage fluctuations and other problems that may be caused by reactive power imbalance, thereby ensuring the safe, stable and efficient operation of the power system.

[0062] The following is a detailed description of the converter fault ride-through control delay compensation method of the present application using a specific embodiment. Figure 2 As shown:

[0063] Step S201: Start.

[0064] Step S202: Estimating the converter control delay T d .

[0065] By testing the reactive current command response of the converter equipment, relevant data is obtained to estimate the control delay time.

[0066] Step S203: T <0.95.

[0067] If U T <0.95, execute step S205; otherwise, execute step S204.

[0068] Step S204: No operation required.

[0069] Step S205: voltage prediction step.

[0070] Based on the estimated control delay, the quantitative relationship between reactive current command and voltage recovery rate is estimated using historical data and modeled through neural network.

[0071] Step S206: According to Upre Calculate the reactive current command.

[0072] The reactive current calculation formula is: I q，ref = k*(1-U pre ).

[0073] Step S207: pre =1?

[0074] If U r =1, execute step S208; otherwise, execute step S205.

[0075] Step S208: End.

[0076] Specifically, at time t1, to predict t1+T d Voltage at time t1+kT c (k=1,2,3...) corresponding to I qrer , substitute it into the model to estimate the voltage recovery rate to obtain the voltage recovery amount in the corresponding period, and predict it section by section until k = T d / T c Complete t1+T d The voltage prediction at each moment provides a basis for the subsequent reactive current command calculation to compensate for the influence of control delay and avoid voltage reverse regulation.

[0077] According to the inverter fault crossing control delay compensation method proposed in the embodiment of the present application, the control delay time can be estimated by detecting the response speed of the reactive current instruction of the inverter device, which is helpful to accurately grasp the working state related parameters of the inverter. When the voltage is less than a certain threshold, the voltage estimation value after the control delay time is predicted, and the voltage situation can be predicted in advance. Then, the reactive current instruction is calculated based on the voltage estimation value, so that when the voltage estimation value is less than the first voltage, the inverter device is controlled to emit reactive power, and when it is greater than the first voltage, the first reactive current is absorbed. The method of flexibly adjusting the reactive current according to different voltage conditions is conducive to improving the stability of transient voltage, and can more effectively deal with the situation of inverter fault crossing, and optimize the operating performance of the inverter under different voltage conditions.

[0078] Next, a converter fault ride-through control delay compensation device proposed according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0079] Figure 3 It is a block diagram of a converter fault ride-through control delay compensation device according to an embodiment of the present application.

[0080] like Figure 3 As shown, the converter fault ride-through control delay compensation device 10 includes: a detection module 100 , a prediction module 200 and a compensation module 300 .

[0081] Specifically, the detection module 100 is used to detect the response speed of the reactive current instruction of the converter device to estimate the control delay time.

[0082] The prediction module 200 is used to predict the voltage estimation value after the control delay time when the voltage is less than a preset threshold.

[0083] The compensation module 300 is used to calculate the reactive current instruction according to the voltage estimation value, so as to control the converter device to generate reactive power when the voltage estimation value is less than the first preset voltage, and to absorb the first reactive current when the voltage estimation value is greater than the first preset voltage, until the voltage estimation value is equal to the first preset voltage.

[0084] Optionally, in one embodiment of the present application, the calculation formula of the reactive current command is:

[0085] I q，ref = k*(1-U pre ),

[0086] Among them, k is the reactive current coefficient, which is generally required to be higher than 1.5, U pre is the predicted voltage value.

[0087] Optionally, in one embodiment of the present application, the compensation module 300 includes: a first judgment unit and an output unit.

[0088] The first judging unit is used to judge whether the voltage estimation value is smaller than the second preset voltage.

[0089] The output unit is used to start outputting a second reactive current when the voltage estimation value is less than a second preset voltage.

[0090] Optionally, in one embodiment of the present application, the compensation module 300 includes: an identification unit and a second judgment unit.

[0091] The identification unit is used to identify the current voltage trend of the voltage.

[0092] The second judgment unit is used to allow the output of a second reactive current when the current voltage trend is a downward trend.

[0093] Optionally, in one embodiment of the present application, the second preset voltage is less than the first preset voltage.

[0094] It should be noted that the above explanation of the converter fault ride-through control delay compensation method embodiment is also applicable to the converter fault ride-through control delay compensation device of this embodiment, and will not be repeated here.

[0095] According to the converter fault crossing control delay compensation device proposed in the embodiment of the present application, the control delay time can be estimated by detecting the response speed of the reactive current instruction of the converter device, which is helpful to accurately grasp the parameters related to the working state of the converter. When the voltage is less than a certain threshold, the voltage estimation value after the control delay time is predicted, and the voltage situation can be predicted in advance. Then, the reactive current instruction is calculated based on the voltage estimation value, so that when the voltage estimation value is less than the first voltage, the converter device is controlled to emit reactive power, and when it is greater than the first voltage, the first reactive current is absorbed. The way of flexibly adjusting the reactive current according to different voltage conditions is conducive to improving the stability of transient voltage, and can more effectively deal with the situation of converter fault crossing, and optimize the operating performance of the converter under different voltage conditions.

[0096] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0097] Memory 401 , processor 402 , and a computer program stored in the memory 401 and executable on the processor 402 .

[0098] When the processor 402 executes the program, the converter fault ride-through control delay compensation method provided in the above embodiment is implemented.

[0099] Furthermore, the electronic device further comprises:

[0100] The communication interface 403 is used for communication between the memory 401 and the processor 402 .

[0101] The memory 401 is used to store computer programs that can be executed on the processor 402 .

[0102] The memory 401 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0103] If the memory 401, the processor 402 and the communication interface 403 are implemented independently, the communication interface 403, the memory 401 and the processor 402 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0104] Optionally, in a specific implementation, if the memory 401, the processor 402 and the communication interface 403 are integrated on a chip, the memory 401, the processor 402 and the communication interface 403 can communicate with each other through an internal interface.

[0105] The processor 402 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0106] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned converter fault ride-through control delay compensation method.

[0107] An embodiment of the present application further provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned converter fault ride-through control delay compensation method.

[0108] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0109] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0110] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0111] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0112] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0113] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0114] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0115] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for compensating a converter fault ride-through control delay, characterized in that: The following steps are involved: Detect the response speed of the reactive current command of the converter equipment to estimate the control delay time; When the voltage is less than a preset threshold, the estimated voltage value after the predictive control delay time is obtained; A reactive current instruction is calculated based on the voltage estimation value to control the converter device to generate reactive power when the voltage estimation value is less than a first preset voltage, and to absorb a first reactive current when the voltage estimation value is greater than the first preset voltage, until the voltage estimation value is equal to the first preset voltage.

2. The method according to claim 1, characterized in that The calculation formula of the reactive current command is: AND q,ref =k*(1-U pre ), Among them, k is the reactive current coefficient, which is generally required to be higher than 1.5, U pre is the recovery value of the terminal voltage.

3. The method according to claim 1, characterized in that After predicting the voltage estimation value after the control delay time, the method further includes: Determining that the voltage estimation value is less than a second preset voltage; If the voltage estimation value is less than the second preset voltage, the second reactive current starts to be output.

4. The method according to claim 3, characterized in that Before starting to output the second reactive current, the method further includes: identifying a current voltage trend of the voltage; When the current voltage trend is a downward trend, the second reactive current is allowed to be output.

5. The method according to claim 3, characterized in that: The second preset voltage is lower than the first preset voltage.

6. A converter fault ride-through control delay compensation device, characterized in that: include: A detection module, used to detect the response speed of the reactive current instruction of the converter device to estimate the control delay time; A prediction module, used to predict the voltage estimation value after the control delay time when the voltage is less than a preset threshold; A compensation module is used to calculate a reactive current instruction based on the voltage estimation value, so as to control the converter device to generate reactive power when the voltage estimation value is less than a first preset voltage, and to absorb a first reactive current when the voltage estimation value is greater than the first preset voltage, until the voltage estimation value is equal to the first preset voltage.

7. The device according to claim 6, characterized in that The calculation formula of the reactive current command is: I q,ref =k*(1-I pre ), Among them, k is the reactive current coefficient, which is generally required to be higher than 1.5, U pre is the predicted voltage value.

8. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for compensating for the fault ride-through control delay of a converter as described in any one of claims 1 to 5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the converter fault ride-through control delay compensation method as described in any one of claims 1 to 5.

10. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the converter fault ride-through control delay compensation method according to any one of claims 1 to 5.

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