Multi-converter parallel coordinated control method and device

Abstract

The present disclosure proposes a multi-converter parallel coordinated control method and device, which are applied to a wind power grid-connected system including a full-power converter unit, wherein the full-power converter unit includes multiple parallel full-power converters, each of which includes a grid-side converter and a machine-side converter, and any one of the full-power converters is selected as the second converter, and each of the remaining full-power converters is selected as the first converter. The method utilizes the DC voltage of the first converter, the AC voltage and the first reactive power of the grid-side converter, the q-axis current component and the d-axis current component of the grid-side converter, the maximum current, the active power reference value and the active power measurement value fed into the wind turbine set, the rated frequency of the wind turbine set, and the second reactive power and the rated voltage of the grid-side converter in the second converter to obtain a first modulation wave and a second modulation wave, and controls the first converter and the second converter in the full-power converter unit based on the first modulation wave and the second modulation wave.

Description

Technical Field

[0001] The present disclosure relates to the field of wind power grid connection, and in particular to a method and device for parallel coordinated control of multiple converters. Background Art

[0002] With the rapid development of renewable energy power generation, wind power generation has gradually occupied a large proportion in the power system. For wind power grid-connected systems, the system to which they are connected is usually a strong power grid, that is, the wind farm does not need to perform relevant active and reactive power regulation functions for access to the power grid. With the large-scale development of wind power, the capacity of wind turbines has gradually increased, and the capacity of the back-to-back power electronic converters configured therein also needs to be increased. A single low-voltage two-level converter is difficult to meet the requirements of a single large-capacity wind power system. At present, the main way to realize a large-capacity converter for wind turbines is to connect converters in parallel. Therefore, there is an urgent need for a collaborative control technology for the parallel connection of multiple converters, so as to better utilize the wind turbines to provide a certain support capability for access to the power grid. Summary of the invention

[0003] The present disclosure aims to solve one of the technical problems in the related art at least to some extent.

[0004] To this end, the first purpose of the present disclosure is to propose a method for coordinated control of multiple converters in parallel, the main purpose of which is to better utilize the wind turbine to provide a certain support capacity for access to the power grid when multiple converters are connected in parallel.

[0005] A second objective of the present disclosure is to provide a multi-converter parallel coordinated control device.

[0006] The third objective of the present disclosure is to provide a multi-converter parallel cooperative control device.

[0007] To achieve the above-mentioned purpose, a first aspect of the present disclosure provides a multi-converter parallel coordinated control method, which is applied to a wind power grid-connected system, wherein the wind power grid-connected system includes a wind turbine, a full-power converter unit and a transformer, wherein the full-power converter unit includes a plurality of parallel full-power converters, each of which includes a grid-side converter and a machine-side converter, wherein the wind turbine is connected to a power grid via the full-power converter unit and the transformer, and one full-power converter is arbitrarily selected as a second converter, and each of the remaining full-power converters is used as a first converter, wherein the method includes:

[0008] For any first converter, obtain the DC voltage, the AC voltage and the first reactive power of the grid-side converter, the q-axis current component and the d-axis current component of the grid-side converter, the maximum current, the active power reference value and the active power measurement value fed into the wind turbine generator set, and the rated frequency of the wind turbine generator set; for the second converter, obtain the second reactive power and the rated voltage of the grid-side converter;

[0009] Calculate a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and calculate a voltage reference value based on the second reactive power and the rated voltage;

[0010] For any first converter, a q-axis current reference value is obtained based on the AC voltage or the first reactive power, and a d-axis current reference value is obtained based on the maximum current, the q-axis current reference value, and the DC voltage; a first modulation wave is generated based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and the grid-side converter in the first converter is controlled based on the first modulation wave;

[0011] A second modulation wave is generated based on the voltage reference value and the phase reference value, and a grid-side converter in the second converter is controlled based on the second modulation wave.

[0012] In one embodiment of the present disclosure, a reference frequency and a phase reference value are calculated based on the rated frequency, the active power reference value and the active power measurement value, including: calculating the reference frequency based on the first regulated power, the active power reference value and the active power measurement value, wherein the first regulated power is obtained based on the first damping coefficient, the reference frequency and the rated frequency; and obtaining the phase reference value based on the reference frequency.

[0013] In one embodiment of the present disclosure, the DC voltage includes a DC voltage measurement value and a DC voltage reference value, and obtaining a d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage includes: calculating a first difference between the DC voltage measurement value and the DC voltage reference value, and obtaining a d-axis current reference value based on the first difference, the maximum current, and the q-axis current reference value.

[0014] In one embodiment of the present disclosure, the first modulation wave is generated based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, including: obtaining a d-axis voltage reference component and a q-axis voltage reference component based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the q-axis current component and the d-axis current component of the grid-side converter; and performing pulse width modulation based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value to generate the first modulation wave.

[0015] In one embodiment of the present disclosure, the second reactive power includes a second reactive power measurement value and a second reactive power reference value, and the voltage reference value calculated based on the second reactive power and the rated voltage includes: the voltage reference value is calculated based on the second regulated power, the second reactive power measurement value and the second reactive power reference value, wherein the second regulated power is obtained based on the second damping coefficient, the voltage reference value and the rated voltage.

[0016] To achieve the above-mentioned purpose, the second aspect of the present disclosure proposes a multi-converter parallel coordinated control device, which is applied to a wind power grid-connected system, wherein the wind power grid-connected system includes a wind turbine, a full-power converter unit and a transformer, wherein the full-power converter unit includes a plurality of full-power converters connected in parallel, each full-power converter includes a grid-side converter and a machine-side converter, and the wind turbine is connected to the grid via the full-power converter unit and the transformer, and one full-power converter is arbitrarily selected as the second converter, and each of the remaining full-power converters is used as the first converter. The device includes:

[0017] An acquisition module is used to acquire, for any first converter, a DC voltage, an AC voltage and a first reactive power of a grid-side converter, a q-axis current component and a d-axis current component of the grid-side converter, a maximum current, an active power reference value and an active power measurement value fed into the wind turbine generator set, and a rated frequency of the wind turbine generator set; and for a second converter, to acquire a second reactive power and a rated voltage of the grid-side converter;

[0018] a calculation module, configured to calculate a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and to calculate a voltage reference value based on the second reactive power and the rated voltage;

[0019] A control module is used to obtain a q-axis current reference value based on the AC voltage or the first reactive power, and to obtain a d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage for any first converter; generate a first modulation wave based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and control the grid-side converter in the first converter based on the first modulation wave; generate a second modulation wave based on the voltage reference value and the phase reference value, and control the grid-side converter in the second converter based on the second modulation wave.

[0020] In one embodiment of the present disclosure, the calculation module is specifically used to: calculate and obtain a reference frequency based on the first regulated power, the active power reference value and the active power measurement value, wherein the first regulated power is obtained based on the first damping coefficient, the reference frequency and the rated frequency; and obtain a phase reference value based on the reference frequency.

[0021] In one embodiment of the present disclosure, the second reactive power includes a second reactive power measurement value and a second reactive power reference value, and the calculation module is specifically used to calculate a voltage reference value based on the second regulated power, the second reactive power measurement value and the second reactive power reference value, wherein the second regulated power is obtained based on the second damping coefficient, the voltage reference value and the rated voltage.

[0022] In one embodiment of the present disclosure, the control module is specifically used to: obtain a d-axis voltage reference component and a q-axis voltage reference component based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the q-axis current component and the d-axis current component of the grid-side converter; and perform pulse width modulation based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value to generate a first modulation wave.

[0023] To achieve the above-mentioned purpose, the third aspect embodiment of the present disclosure proposes a multi-converter parallel cooperative control device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the multi-converter parallel cooperative control method of the first aspect embodiment of the present disclosure.

[0024] In one or more embodiments of the present disclosure, the present disclosure is applied to a wind power grid-connected system, the wind power grid-connected system includes a wind turbine, a full-power converter unit and a transformer, the full-power converter unit includes a plurality of full-power converters connected in parallel, each full-power converter includes a grid-side converter and a machine-side converter, the wind turbine is connected to the grid via the full-power converter unit and the transformer, one full-power converter is arbitrarily selected as the second converter, and each of the remaining full-power converters is used as the first converter, the method includes: for any first converter, obtaining a DC voltage, an AC voltage and a first reactive power of the grid-side converter, a q-axis current component and a d-axis current component of the grid-side converter, a maximum current, an active power reference value and an active power measurement value fed into the wind turbine, and a rated frequency of the wind turbine, and for the second Converter, obtain the second reactive power and rated voltage of the grid-side converter; calculate the reference frequency and phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and calculate the voltage reference value based on the second reactive power and the rated voltage; for any first converter, obtain the q-axis current reference value based on the AC voltage or the first reactive power, and obtain the d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage; generate a first modulation wave based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and control the grid-side converter in the first converter based on the first modulation wave; generate a second modulation wave based on the voltage reference value and the phase reference value, and control the grid-side converter in the second converter based on the second modulation wave. In this case, the DC voltage of the first converter, the AC voltage and the first reactive power of the grid-side converter in the first converter, the q-axis current component and the d-axis current component of the grid-side converter in the first converter, the maximum current of the first converter, the active power reference value and the active power measurement value fed into the wind turbine, the rated frequency of the wind turbine, the second reactive power and the rated voltage of the grid-side converter in the second converter are integrated to obtain the first modulation wave and the second modulation wave. The first converter and the second converter in the full-power converter unit are controlled based on the first modulation wave and the second modulation wave, wherein the rated frequency, the active power reference value, the active power measurement value, the second reactive power and the rated voltage of the second converter are combined to calculate the reference frequency, the phase reference value, and the voltage reference value of the grid-side converter in the second converter to participate in the generation of the first modulation wave and the second modulation wave. At this time, when multiple converters are connected in parallel, the wind turbine can be better utilized to provide a certain support capacity for access to the power grid.

[0025] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation of the present disclosure or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the specific implementation or prior art description. Obviously, the drawings described below are some implementations of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. The above and / or additional aspects and advantages of the present disclosure will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, in which:

[0027] Figure 1 A schematic diagram of the topological structure of a wind power grid-connected system provided in an embodiment of the present disclosure;

[0028] Figure 2 A schematic diagram of a flow chart of a multi-converter parallel coordinated control method provided in an embodiment of the present disclosure;

[0029] Figure 3 A control principle diagram of a grid-side converter in a first converter provided in an embodiment of the present disclosure;

[0030] Figure 4 A block diagram of a multi-converter parallel cooperative control device provided by an embodiment of the present disclosure;

[0031] Figure 5 The block diagram of a multi-converter parallel cooperative control device used to implement the multi-converter parallel cooperative control method of the embodiment of the present disclosure. DETAILED DESCRIPTION

[0032] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the embodiments of the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the embodiments of the present disclosure as detailed in the appended claims.

[0033] 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 disclosure. 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 more 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.

[0034] 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. It should also be understood that the term "and / or" used in the present disclosure refers to and includes any or all possible combinations of one or more associated listed items.

[0035] Embodiments of the present disclosure are described in detail below, examples of which 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 disclosure, and should not be construed as limiting the present disclosure.

[0036] The present disclosure provides a method and device for coordinated control of multiple converters in parallel, the main purpose of which is to better utilize wind turbines to provide a certain support capability for access to a power grid when multiple converters are connected in parallel.

[0037] The multi-converter parallel coordinated control method and device disclosed in the present invention are applied to a wind power grid-connected system. It is easy to understand that the wind power grid-connected system includes a wind turbine, a full-power converter unit and a transformer, and the wind turbine is connected to the power grid via the full-power converter unit and the transformer. The full-power converter unit includes a plurality of full-power converters connected in parallel. Each full-power converter is a back-to-back converter. Each full-power converter includes two converters, a grid-side converter and a machine-side converter. That is, the wind turbine is connected to the transformer via the grid-side converter and the machine-side converter of each full-power converter.

[0038] In the present disclosure, the number of full-power converters in a full-power converter unit may be two, or three or more. If the number of full-power converters is two, one full-power converter is arbitrarily selected as the second converter, and the remaining one full-power converter is used as the first converter; if the number of full-power converters is three, one full-power converter is arbitrarily selected as the second converter, and each of the remaining full-power converters is used as the first converter. The multi-converter parallel coordinated control method and device disclosed in the present disclosure is aimed at the parallel connection of full-power converters, and can generate different modulation waves based on different parameters for controlling the first converter and the second converter respectively.

[0039] Take the case where the number of full power converters is two as an example. Figure 1 Schematic diagram of the topological structure of the wind power grid-connected system provided by the embodiment of the present disclosure. Figure 1As shown, the wind power grid-connected system includes a wind turbine and a permanent magnet synchronous generator (PMSG). The wind turbine and the permanent magnet synchronous generator constitute a wind turbine unit. The wind power grid-connected system also includes two full-power converters and a step-up transformer. The two full-power converters are connected in parallel. Each full-power converter includes a grid-side converter and a machine-side converter. The grid-side converter of each full-power converter is connected to the grid via a step-up transformer. The machine-side converter of each full-power converter is connected to the permanent magnet synchronous generator. Each full-power converter also includes a centralized capacitor connecting the DC side positive pole and the DC side negative pole of the grid-side converter.

[0040] In a first embodiment, Figure 2 The flowchart of the multi-converter parallel coordinated control method provided by the embodiment of the present disclosure is as follows. Figure 2 As shown, the multi-converter parallel coordinated control method includes the following steps:

[0041] Step S11, for any first converter, obtain the DC voltage, the AC voltage and the first reactive power of the grid-side converter, the q-axis current component and the d-axis current component of the grid-side converter, the maximum current, the active power reference value and the active power measurement value fed into the wind turbine, and the rated frequency of the wind turbine; for the second converter, obtain the second reactive power and the rated voltage of the grid-side converter.

[0042] Specifically, in step S11, for any first converter, multiple parameters such as DC voltage, AC voltage and first reactive power of the grid-side converter, q-axis current component and d-axis current component of the grid-side converter, maximum current, active power reference value and active power measurement value fed into the wind turbine, and rated frequency of the wind turbine are obtained. The DC voltage of each first converter includes a DC voltage measurement value and a DC voltage rated value. The DC voltage measurement value can be represented by the symbol u dc The DC voltage rating can be represented by the symbol u dcref The AC voltage of the grid-side converter includes the AC voltage measurement value and the AC voltage rated value. The AC voltage measurement value of the grid-side converter can be represented by the symbol u g The AC voltage rating of the grid-side converter can be represented by the symbol u gref The first reactive power of the grid-side converter includes a first reactive power measurement value and a first reactive power rated value. The first reactive power measurement value can be represented by the symbol Q g The first reactive power rating can be represented by the symbol Q gref The q-axis current component of the AC side of the grid-side converter can be represented by the symbol i gq The d-axis current component of the AC side of the grid-side converter can be represented by the symbol i gdThe maximum current of the first converter can be represented by the symbol i max The active power reference value fed into the wind turbine can be represented by the symbol P ref The reference value of the active power fed into the wind turbine is the active power that the entire system expects the wind turbine to feed in. The measured value of the active power fed into the wind turbine can be represented by the symbol P. The rated frequency of the wind turbine can be represented by the symbol ω ref .

[0043] In step S11, for the second converter, the second reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter are obtained. The second reactive power includes a second reactive power measurement value and a second reactive power rated value. The second reactive power measurement value can be represented by the symbol Q. The second reactive power rated value can be represented by the symbol Q ref The rated voltage of the grid-side converter in the second converter can be represented by V mref express.

[0044] Step S12: obtaining a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and obtaining a voltage reference value based on the second reactive power and the rated voltage.

[0045] In step S12, the reference frequency and the phase reference value are calculated based on the rated frequency, the active power reference value and the active power measurement value, including: calculating the reference frequency based on the first regulated power, the active power reference value and the active power measurement value, wherein the first regulated power is obtained based on the first damping coefficient, the reference frequency and the rated frequency; and obtaining the phase reference value based on the reference frequency. The reference frequency can be represented by the symbol ω. The phase reference value can be represented by the symbol 2.

[0046] Specifically, the first adjustment power and the active power reference value P are calculated. ref The sum of the sum and then calculate the difference between the sum and the active power measurement value P, and send the difference to the PI regulator to use the first inertia control parameter J p Perform integral calculation to obtain the reference frequency ω. That is, the reference frequency ω can be obtained by formula (1):

[0047]

[0048] Among them, J p represents the first inertia control parameter, t represents time, D p represents the first damping control parameter (i.e., the first damping coefficient), based on (ω ref -)D pThe first regulated power is obtained. The reference frequency ω is sent to the PI regulator for integral calculation to obtain the phase reference value θ. That is, the phase reference value satisfies

[0049] In step S12, the voltage reference value of the grid-side converter in the second converter is calculated based on the second reactive power and the rated voltage, including: the voltage reference value is calculated based on the second regulated power, the second reactive power measurement value and the second reactive power reference value, wherein the second regulated power is obtained based on the second damping coefficient, the voltage reference value and the rated voltage. The voltage reference value can be represented by the symbol V m express.

[0050] Specifically, the second adjustment power and the second reactive power reference value Q are calculated ref The sum of the sum and then calculate the difference between the sum and the second reactive power measurement value Q, and send the difference to the PI regulator to use the second inertia control parameter J q Perform integral calculation to obtain the voltage reference value V m . Calculate the rated voltage V mref and voltage reference value V m The difference is sent to the PI regulator and the second damping coefficient (i.e., the second damping control parameter) D q The product is then multiplied to obtain the second regulated power. Specifically, the voltage reference value V m satisfy:

[0051]

[0052] In step S12, the reference frequency ω and the phase reference value formula can replace the traditional PLL to generate a phase-locked loop, and the reference frequency ω and the phase reference value obtained in step S12 participate in the subsequent control of the first converter, so as to achieve the effect of regulating the power of the first converter. The phase reference value and the voltage reference value obtained in step S12 participate in the subsequent control of the second converter, so as to achieve the effect of regulating the power of the second converter.

[0053] Step S13, for any first converter, obtain a q-axis current reference value based on the AC voltage or the first reactive power, and obtain a d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage; generate a first modulation wave based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and control the grid-side converter in the first converter based on the first modulation wave.

[0054] The data processing based on step S13 can generate the first modulation wave corresponding to each first converter, and then control the grid-side converter in each first converter based on the first modulation wave. Taking a first converter as an example, the specific data processing process is as follows:

[0055] In step S13, the q-axis current reference value of the grid-side converter can be obtained based on the AC voltage of the grid-side converter, or the q-axis current reference value of the grid-side converter can be obtained based on the first reactive power of the grid-side converter. gqref express.

[0056] In some embodiments, obtaining a q-axis current reference value of the grid-side converter based on the AC voltage of the grid-side converter includes obtaining the q-axis current reference value of the grid-side converter based on the AC voltage measurement value and the AC voltage rating of the grid-side converter. Obtaining the q-axis current reference value of the grid-side converter based on the first reactive power includes obtaining the q-axis current reference value of the grid-side converter based on the first reactive power measurement value and the first reactive power rating.

[0057] Specifically, Figure 3 A control schematic diagram of a grid-side converter in a first converter provided in an embodiment of the present disclosure.

[0058] like Figure 3 As shown, the q-axis current reference value i of the grid-side converter is generated gqref There are two ways. Method 1 is to calculate the first reactive power measurement value Q g With the first reactive power rating Q gref The difference is sent to the PI regulator to calculate the q-axis current reference value i of the grid-side converter. gqref Method 2 is to calculate the AC voltage rating u of the grid-side converter gref The AC voltage measurement value u of the grid-side converter g The difference is sent to the PI regulator to calculate the q-axis current reference value i of the grid-side converter. gqref Method 1 and method 2 can be selected based on needs.

[0059] In step S13, a d-axis current reference value is obtained based on the maximum current, the q-axis current reference value, and the DC voltage, including: calculating a first difference between the DC voltage measurement value and the DC voltage reference value, and obtaining a d-axis current reference value based on the first difference, the maximum current, and the q-axis current reference value.

[0060] Specifically, Figure 3 As shown, calculate the DC voltage measurement value u dc With DC voltage reference value u dcrefThe first difference is sent to the PI regulator to calculate the first target d-axis current reference value i of the grid-side converter. gdref1 , based on the q-axis current reference value i of the grid-side converter gqref and the maximum current i max Obtain the second target d-axis current reference value i of the grid-side converter gdref2 , the second target d-axis current reference value i of the grid-side converter gdref2 satisfy:

[0061]

[0062] like Figure 3 As shown, the minimum value of the first target d-axis current reference value of the grid-side converter and the second target d-axis current reference value of the grid-side converter is selected as the d-axis current reference value of the grid-side converter, that is, the d-axis current reference value i of the grid-side converter gdref satisfy:

[0063] i gdref =min(i gdref1 ,i gdref2 ).

[0064] In step S13, a first modulation wave is generated based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, including: obtaining a d-axis voltage reference component and a q-axis voltage reference component based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the q-axis current component and the d-axis current component of the grid-side converter; and performing pulse width modulation based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value to generate the first modulation wave.

[0065] In step S13, based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the q-axis current component and the d-axis current component of the grid-side converter, a d-axis voltage reference component and a q-axis voltage reference component are obtained, including: obtaining a first voltage based on the d-axis current reference value and the d-axis current component of the grid-side converter, obtaining a second voltage based on the reference frequency and the q-axis current component of the grid-side converter, obtaining a third voltage based on the q-axis current reference value and the q-axis current component of the grid-side converter, obtaining a fourth voltage based on the reference frequency and the d-axis current component of the grid-side converter, and obtaining a d-axis voltage reference component and a q-axis voltage reference component of the grid-side converter based on the first voltage, the second voltage, the third voltage and the fourth voltage. In addition, a d-axis voltage component u is obtained based on the AC voltage measurement value of the grid-side converter. d and the q-axis voltage component u q .

[0066] Specifically, Figure 3 As shown, calculate the d-axis current reference value i gdrefThe d-axis current component i of the AC side of the grid-side converter gd The difference is sent to the PI regulator (i.e. proportional integral controller) to calculate the first voltage V 1 , based on the q-axis current component i on the AC side of the grid-side converter gq , the inductive reactance value of the grid-side converter ω g L g Obtain the second voltage V 2 , where the frequency ω g The value of is equal to the reference frequency ω. d Add the first voltage V 1 Subtract the second voltage V 2 Get the d-axis voltage reference component U gd . Calculate the q-axis current reference value i gqref The q-axis current component i of the AC side of the grid-side converter gq The difference is sent to the PI regulator (i.e. proportional integral controller) to calculate the third voltage V 3 , based on the d-axis current component i on the AC side of the grid-side converter gd , the inductive reactance value of the grid-side converter ω g L g Obtain the fourth voltage V 4 , the q-axis voltage component u q Add the third voltage V 3 Then add the fourth voltage V 4 Get the q-axis voltage reference component U gq .

[0067] In step S13, pulse width modulation is performed based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value to generate a first modulation wave, including: based on the phase reference value, the d-axis voltage reference component U gd and the q-axis voltage reference component U gq The first three-phase voltage reference value is obtained by using the Park inverse transformation, and the first three-phase voltage reference value is pulse-width modulated to generate a first modulation wave. In this way, it is possible to better participate in the DC voltage regulation of the grid-side converter, better provide certain support to the grid, and ensure the stability of the DC voltage.

[0068] Step S14: generating a second modulation wave based on the voltage reference value and the phase reference value, and controlling the grid-side converter in the second converter based on the second modulation wave.

[0069] The data processing based on step S14 can generate a second modulation wave corresponding to the second converter, and then control the grid-side converter in the second converter based on the second modulation wave. Different from the data processing process of the first converter in step S13, step S14 directly generates the second modulation wave with the help of the voltage reference value and phase reference calculated in step S12.

[0070] Specifically, in step S14, a second modulation wave is generated based on the voltage reference value and phase reference value of the grid-side converter in the second converter, including: based on the voltage reference value and phase reference value of the grid-side converter in the second converter, using Park inverse transformation to obtain a second three-phase voltage reference value, and performing pulse width modulation on the second three-phase voltage reference value to generate a second modulation wave.

[0071] In the multi-converter parallel coordinated control method of the embodiment of the present disclosure, it is applied to a wind power grid-connected system, the wind power grid-connected system includes a wind turbine, a full-power converter and a transformer, the full-power converter includes a grid-side converter and a machine-side converter, the wind turbine is connected to the grid via the full-power converter and the transformer, one converter in the full-power converter is selected as the first converter, and the remaining converter is the second converter, the method includes: obtaining the DC voltage of the first converter, the AC voltage and reactive power of the grid-side converter in the first converter, the q-axis current component and the d-axis current component of the grid-side converter in the first converter, the maximum current of the first converter, the active power reference value and the active power measurement value fed into the wind turbine, the rated frequency of the wind turbine, the reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter; based on the rated frequency, the active power reference value, the active power measurement value ... The reference frequency and phase reference value are calculated based on the current value and the active power measurement value, and the voltage reference value of the grid-side converter in the second converter is calculated based on the reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter; the q-axis current reference value is obtained based on the AC voltage of the grid-side converter in the first converter or the reactive power of the grid-side converter in the first converter, and the d-axis current reference value is obtained based on the maximum current, the q-axis current reference value, and the DC voltage; a first modulation wave is generated based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter in the first converter, and the grid-side converter in the first converter is controlled based on the first modulation wave; a second modulation wave is generated based on the voltage reference value and the phase reference value of the grid-side converter in the second converter, and the grid-side converter in the second converter is controlled based on the second modulation wave. In this case, the DC voltage of the first converter, the AC voltage and reactive power of the grid-side converter in the first converter, the q-axis current component and the d-axis current component of the grid-side converter in the first converter, the maximum current of the first converter, the active power reference value and the active power measurement value fed into the wind turbine, the rated frequency of the wind turbine, the reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter are integrated to obtain the first modulation wave and the second modulation wave. The two converters of the full-power converter are controlled based on the first modulation wave and the second modulation wave. The rated frequency, the active power reference value, the active power measurement value, the reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter are combined to obtain the reference frequency, the phase reference value and the voltage reference value of the grid-side converter in the second converter to participate in the generation of the first modulation wave and the second modulation wave. At this time, when multiple converters are connected in parallel, the wind turbine can be better utilized to provide a certain support capacity for access to the power grid.

[0072] The following are embodiments of the device disclosed herein, which can be used to execute the method embodiments disclosed herein. For details not disclosed in the device embodiments disclosed herein, please refer to the method embodiments disclosed herein.

[0073] The present disclosure relates to a multi-converter parallel coordinated control device. The multi-converter parallel coordinated control device can better utilize the wind turbine to provide a certain support capacity for accessing the power grid when multiple converters are connected in parallel. The multi-converter parallel coordinated control device is applied to a wind power grid-connected system, which includes a wind turbine, a full-power converter unit and a transformer. The full-power converter unit includes a plurality of parallel full-power converters, each of which includes a grid-side converter and a machine-side converter. The wind turbine is connected to the power grid via the full-power converter unit and the transformer. One full-power converter is arbitrarily selected as the second converter, and each of the remaining full-power converters is used as the first converter.

[0074] See also Figure 4 , Figure 4 A block diagram of a multi-converter parallel coordinated control device provided by an embodiment of the present disclosure. The multi-converter parallel coordinated control device 10 includes an acquisition module 11, a calculation module 12 and a control module 13, wherein:

[0075] An acquisition module is used to acquire, for any first converter, a DC voltage, an AC voltage and a first reactive power of a grid-side converter, a q-axis current component and a d-axis current component of the grid-side converter, a maximum current, an active power reference value and an active power measurement value fed into the wind turbine generator set, and a rated frequency of the wind turbine generator set; and for a second converter, to acquire a second reactive power and a rated voltage of the grid-side converter;

[0076] A calculation module, configured to calculate a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and to calculate a voltage reference value based on the second reactive power and the rated voltage;

[0077] A control module is used to obtain a q-axis current reference value based on an AC voltage or a first reactive power for any first converter, and to obtain a d-axis current reference value based on a maximum current, a q-axis current reference value, and a DC voltage; to generate a first modulation wave based on the q-axis current reference value, the d-axis current reference value, a reference frequency, a phase reference value, and a q-axis current component and a d-axis current component of a grid-side converter, and to control the grid-side converter in the first converter based on the first modulation wave; to generate a second modulation wave based on a voltage reference value and a phase reference value, and to control the grid-side converter in the second converter based on the second modulation wave.

[0078] Optionally, the calculation module 12 is specifically used to: calculate a reference frequency based on the first regulated power, an active power reference value and an active power measurement value, wherein the first regulated power is obtained based on a first damping coefficient, a reference frequency and a rated frequency; and obtain a phase reference value based on the reference frequency.

[0079] Optionally, the second reactive power includes a second reactive power measurement value and a second reactive power reference value, and the calculation module is specifically used to: calculate a voltage reference value based on the second regulated power, the second reactive power measurement value and the second reactive power reference value, wherein the second regulated power is obtained based on the second damping coefficient, the voltage reference value and the rated voltage.

[0080] Optionally, the control module 13 is specifically used to: obtain a d-axis voltage reference component and a q-axis voltage reference component based on a q-axis current reference value, a d-axis current reference value, a reference frequency, a q-axis current component and a d-axis current component of the grid-side converter; and perform pulse width modulation based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value to generate a first modulation wave.

[0081] It should be noted that the aforementioned explanation of the embodiment of the multi-converter parallel cooperative control method is also applicable to the multi-converter parallel cooperative control device of this embodiment, and will not be repeated here.

[0082] In the multi-converter parallel cooperative control device of the embodiment of the present disclosure, the acquisition module is used to obtain, for any first converter, the DC voltage, the AC voltage and the first reactive power of the grid-side converter, the q-axis current component and the d-axis current component of the grid-side converter, the maximum current, the active power reference value and the active power measurement value fed into the wind turbine group, and the rated frequency of the wind turbine group; for the second converter, the second reactive power and the rated voltage of the grid-side converter are obtained; the calculation module is used to calculate the reference frequency and the phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and the second reactive power and the rated voltage are obtained based on the second reactive power and the rated frequency. The control module is used to obtain a q-axis current reference value based on the AC voltage or the first reactive power for any first converter, and to obtain a d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage; a first modulation wave is generated based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and the grid-side converter in the first converter is controlled based on the first modulation wave; a second modulation wave is generated based on the voltage reference value and the phase reference value, and the grid-side converter in the second converter is controlled based on the second modulation wave. In this case, the DC voltage of the first converter, the AC voltage and reactive power of the grid-side converter in the first converter, the q-axis current component and the d-axis current component of the grid-side converter in the first converter, the maximum current of the first converter, the active power reference value and the active power measurement value fed into the wind turbine, the rated frequency of the wind turbine, the reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter are integrated to obtain the first modulation wave and the second modulation wave. The two converters of the full-power converter are controlled based on the first modulation wave and the second modulation wave. The rated frequency, the active power reference value, the active power measurement value, the reactive power of the grid-side converter in the second converter and the rated voltage of the grid-side converter in the second converter are combined to obtain the reference frequency, the phase reference value and the voltage reference value of the grid-side converter in the second converter to participate in the generation of the first modulation wave and the second modulation wave. At this time, when multiple converters are connected in parallel, the wind turbine can be better utilized to provide a certain support capacity for access to the power grid.

[0083] According to an embodiment of the present disclosure, the present disclosure also provides a multi-converter parallel cooperative control device, a readable storage medium and a computer program product.

[0084] Figure 5is a block diagram of a multi-converter parallel cooperative control device used to implement the multi-converter parallel cooperative control method of an embodiment of the present disclosure. The multi-converter parallel cooperative control device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The multi-converter parallel cooperative control device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable electronic devices and other similar computing devices. The components shown in the present disclosure, the connections and relationships of the components, and the functions of the components are merely examples and are not intended to limit the implementation of the present disclosure described and / or required in the present disclosure.

[0085] like Figure 5 As shown, the multi-converter parallel cooperative control device 20 includes a computing unit 21, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 22 or a computer program loaded from a storage unit 28 to a random access memory (RAM) 23. In the RAM 23, various programs and data required for the operation of the multi-converter parallel cooperative control device 20 can also be stored. The computing unit 21, the ROM 22, and the RAM 23 are connected to each other via a bus 24. An input / output (I / O) interface 25 is also connected to the bus 24.

[0086] Multiple components in the multi-converter parallel cooperative control device 20 are connected to the I / O interface 25, including: an input unit 26, such as a keyboard, a mouse, etc.; an output unit 27, such as various types of displays, speakers, etc.; a storage unit 28, such as a disk, an optical disk, etc., which is communicatively connected to the computing unit 21; and a communication unit 29, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 29 allows the multi-converter parallel cooperative control device 20 to exchange information / data with other multi-converter parallel cooperative control devices through a computer network such as the Internet and / or various telecommunication networks.

[0087] The computing unit 21 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 21 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc. The computing unit 21 performs the various methods and processes described above, such as executing a multi-converter parallel cooperative control method. For example, in some embodiments, the multi-converter parallel cooperative control method may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit 28. In some embodiments, part or all of the computer program may be loaded and / or installed on the multi-converter parallel cooperative control device 20 via the ROM 22 and / or the communication unit 29. When the computer program is loaded into the RAM 23 and executed by the computing unit 21, one or more steps of the multi-converter parallel cooperative control method described above may be performed. Alternatively, in other embodiments, the computing unit 21 may be configured to execute the multi-converter parallel coordinated control method in any other appropriate manner (for example, by means of firmware).

[0088] Various embodiments of the systems and techniques described above in the present disclosure may be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0089] The program code for implementing the method of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0090] In the present disclosure, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or electronic device, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage electronic device, a magnetic storage electronic device, or any suitable combination of the foregoing.

[0091] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0092] The systems and techniques described herein can be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), the Internet, and a blockchain network.

[0093] A computer system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship between the client and the server is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services ("Virtual Private Server", or "VPS" for short). The server may also be a server of a distributed system, or a server combined with a blockchain.

[0094] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this disclosure is not limited here.

[0095] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for coordinated control of multiple converters in parallel, characterized in that: Applied to a wind power grid-connected system, the wind power grid-connected system includes a wind turbine, a full-power converter unit and a transformer, the full-power converter unit includes a plurality of full-power converters connected in parallel, each full-power converter includes a grid-side converter and a machine-side converter, the wind turbine is connected to the grid via the full-power converter unit and the transformer, one full-power converter is arbitrarily selected as the second converter, and each of the remaining full-power converters is used as the first converter, the method includes: For any first converter, obtain the DC voltage, the AC voltage and the first reactive power of the grid-side converter, the q-axis current component and the d-axis current component of the grid-side converter, the maximum current, the active power reference value and the active power measurement value fed into the wind turbine generator set, and the rated frequency of the wind turbine generator set; for the second converter, obtain the second reactive power and the rated voltage of the grid-side converter; Calculate a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and calculate a voltage reference value based on the second reactive power and the rated voltage; For any first converter, a q-axis current reference value is obtained based on the AC voltage or the first reactive power, and a d-axis current reference value is obtained based on the maximum current, the q-axis current reference value, and the DC voltage; a first modulation wave is generated based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and the grid-side converter in the first converter is controlled based on the first modulation wave; generating a second modulation wave based on the voltage reference value and the phase reference value, and controlling a grid-side converter in the second converter based on the second modulation wave; The second reactive power includes a second reactive power measurement value and a second reactive power reference value, and the voltage reference value is calculated based on the second reactive power and the rated voltage, including: A voltage reference value is calculated based on a second regulated power, a second reactive power measurement value and a second reactive power reference value, wherein the second regulated power is obtained based on a second damping coefficient, the voltage reference value and the rated voltage; wherein the method comprises: calculating the sum of the second regulated power and the second reactive power reference value, and then calculating the difference between the summed result and the second reactive power measurement value, and sending the difference to a PI regulator for integral calculation using a second inertia control parameter, thereby obtaining a voltage reference value.

2. The multi-converter parallel coordinated control method according to claim 1, characterized in that: Calculating a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value includes: A reference frequency is calculated based on the first regulated power, the active power reference value and the active power measurement value, wherein the first regulated power is obtained based on the first damping coefficient, the reference frequency and the rated frequency; and a phase reference value is obtained based on the reference frequency.

3. The multi-converter parallel coordinated control method according to claim 2, characterized in that: The DC voltage includes a DC voltage measurement value and a DC voltage reference value, and obtaining a d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage includes: A first difference between a DC voltage measurement value and a DC voltage reference value is calculated, and a d-axis current reference value is obtained based on the first difference, the maximum current, and the q-axis current reference value.

4. The multi-converter parallel coordinated control method according to claim 3, characterized in that: The generating a first modulation wave based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter comprises: A d-axis voltage reference component and a q-axis voltage reference component are obtained based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the q-axis current component and the d-axis current component of the grid-side converter; and a first modulation wave is generated by pulse width modulation based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value.

5. A multi-converter parallel coordinated control device, characterized in that: Applicable to a wind power grid-connected system, the wind power grid-connected system includes a wind turbine, a full-power converter unit and a transformer, the full-power converter unit includes a plurality of full-power converters connected in parallel, each full-power converter includes a grid-side converter and a machine-side converter, the wind turbine is connected to the grid via the full-power converter unit and the transformer, one full-power converter is arbitrarily selected as the second converter, and each of the remaining full-power converters is used as the first converter, the device includes: An acquisition module is used to acquire, for any first converter, a DC voltage, an AC voltage and a first reactive power of a grid-side converter, a q-axis current component and a d-axis current component of the grid-side converter, a maximum current, an active power reference value and an active power measurement value fed into the wind turbine generator set, and a rated frequency of the wind turbine generator set; and for a second converter, to acquire a second reactive power and a rated voltage of the grid-side converter; a calculation module, configured to calculate a reference frequency and a phase reference value based on the rated frequency, the active power reference value and the active power measurement value, and to calculate a voltage reference value based on the second reactive power and the rated voltage, wherein the second reactive power includes a second reactive power measurement value and a second reactive power reference value; A control module, for obtaining, for any first converter, a q-axis current reference value based on the AC voltage or the first reactive power, and a d-axis current reference value based on the maximum current, the q-axis current reference value, and the DC voltage; generating a first modulation wave based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the phase reference value, the q-axis current component and the d-axis current component of the grid-side converter, and controlling the grid-side converter in the first converter based on the first modulation wave; generating a second modulation wave based on the voltage reference value and the phase reference value, and controlling the grid-side converter in the second converter based on the second modulation wave; The calculation module is also used to calculate a voltage reference value based on the second regulated power, the second reactive power measurement value and the second reactive power reference value, wherein the second regulated power is obtained based on the second damping coefficient, the voltage reference value and the rated voltage; wherein, it includes: calculating the sum of the second regulated power and the second reactive power reference value, and then calculating the difference between the summed result and the second reactive power measurement value, and sending the difference to the PI regulator for integration calculation using the second inertia control parameter, thereby obtaining the voltage reference value.

6. The multi-converter parallel coordinated control device according to claim 5, characterized in that: The calculation module is specifically used to calculate and obtain a reference frequency based on a first regulated power, the active power reference value and the active power measurement value, wherein the first regulated power is obtained based on a first damping coefficient, the reference frequency and the rated frequency; A phase reference value is obtained based on a reference frequency.

7. The multi-converter parallel coordinated control device according to claim 5, characterized in that: The control module is specifically used to: obtain a d-axis voltage reference component and a q-axis voltage reference component based on the q-axis current reference value, the d-axis current reference value, the reference frequency, the q-axis current component and the d-axis current component of the grid-side converter; A first modulation wave is generated by pulse width modulation based on the d-axis voltage reference component, the q-axis voltage reference component and the phase reference value.

8. A multi-converter parallel coordinated control device, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the multi-converter parallel cooperative control method according to any one of claims 1 to 4.

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