Voltage synchronization method and apparatus, storage medium, and electronic device

Abstract

The application provides a voltage synchronization method and device, a storage medium and an electronic device, relates to the technical field of control, and can be applied to a power conversion system. The system comprises a grid-forming converter and an alternating current bus. The output end of the grid-forming converter is connected to the alternating current bus. The alternating current bus is connected to a power grid through a grid-connected switch. The bus voltage of the alternating current bus and the grid voltage of the power grid can be collected. A virtual current is calculated based on the bus voltage and the grid voltage. A virtual output power is calculated according to the bus voltage and the virtual current. A trigonometric function value of the phase angle difference between the bus voltage and the grid voltage is determined according to the amplitude of the virtual output power and the bus voltage. A synchronous regulation power is constructed according to the trigonometric function value. The synchronous regulation power is input into the active control loop of the grid-forming converter, so that the output frequency of the grid-forming converter is adjusted based on the synchronous regulation power through the active control loop, and the bus voltage is synchronized with the grid voltage. Voltage synchronization can be quickly and accurately realized.

Description

Technical Field

[0001] This application relates to the field of control technology, and in particular to a voltage synchronization method, apparatus, storage medium and electronic device. Background Technology

[0002] With the large-scale integration of new energy sources, independent microgrids composed of power electronic converters are becoming increasingly common in distribution networks. When a microgrid switches from off-grid mode to grid-connected mode, the main converter needs to quickly and accurately complete voltage synchronization to avoid closing shock.

[0003] However, traditional synchronization methods based on phase-locked loops and PI control have problems such as complex control structures and difficult parameter tuning, and are prone to frequency fluctuations during the synchronization process, making it difficult to meet the requirements of fast and accurate voltage synchronization. Summary of the Invention

[0004] The technical problem to be solved by this application is to provide a voltage synchronization method, device, storage medium, and electronic device, which enables voltage synchronization quickly and accurately. The specific solution is as follows:

[0005] A voltage synchronization method is applied to a power conversion system, the power conversion system including a grid-type converter and an AC bus, the output terminal of the grid-type converter being connected to the AC bus, and the AC bus being connected to the power grid through a grid-connected switch, the method comprising:

[0006] Collect the bus voltage of the AC bus and the grid voltage of the power grid;

[0007] Calculate the virtual current based on the bus voltage and the grid voltage;

[0008] Calculate the virtual output power based on the bus voltage and the virtual current;

[0009] Based on the virtual output power and the amplitude of the bus voltage, determine the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage;

[0010] The synchronous adjustment power is constructed based on the trigonometric function value of the phase angle difference;

[0011] The synchronous regulation power is input into the active power control loop of the grid converter, so that the output frequency of the grid converter is adjusted by the active power control loop based on the synchronous regulation power, so that the bus voltage is synchronized with the grid voltage.

[0012] Optionally, in the above method, calculating the virtual current based on the bus voltage and the grid voltage includes:

[0013] Obtain the virtual impedance;

[0014] The grid voltage and the bus voltage are vectorized to obtain the grid voltage vector and the bus voltage vector;

[0015] The virtual current is calculated based on the ratio of the vector difference between the bus voltage vector and the grid voltage vector to the virtual impedance.

[0016] Optionally, in the above method, calculating the virtual output power based on the bus voltage and the virtual current includes:

[0017] The virtual output power is calculated based on the product of the complex conjugate of the bus voltage and the virtual current.

[0018] Optionally, in the above method, determining the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage includes:

[0019] The product of the virtual reactive power in the virtual output power and the virtual impedance is divided by the product of the square of the amplitude of the bus voltage and a preset coefficient to calculate the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage.

[0020] Optionally, in the above method, constructing the synchronous regulation power based on the trigonometric function value of the phase angle difference includes:

[0021] The synchronous adjustment power is obtained by multiplying the trigonometric function value of the phase angle difference with the preset maximum value of the synchronous adjustment power.

[0022] Optionally, in the above method, the step of inputting the synchronous regulation power into the active power control loop of the grid-type converter, so as to adjust the output frequency of the grid-type converter based on the synchronous regulation power through the active power control loop, includes:

[0023] The synchronous regulation power is input into the active power control loop as a compensation amount for the active power reference value of the grid-type converter.

[0024] The active power control loop generates an angular frequency increment based on the synchronously regulated power.

[0025] The output frequency of the grid converter is adjusted based on the angular frequency increment.

[0026] A voltage synchronization device is applied to a power conversion system, the power conversion system including a grid-type converter and an AC bus, the output terminal of the grid-type converter being connected to the AC bus, and the AC bus being connected to the power grid via a grid-connected switch, the device comprising:

[0027] The acquisition unit is used to acquire the bus voltage of the AC bus and the grid voltage of the power grid;

[0028] The first calculation unit is used to calculate the virtual current based on the bus voltage and the grid voltage;

[0029] The second calculation unit is used to calculate the virtual output power based on the bus voltage and the virtual current;

[0030] The determining unit is used to determine the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage;

[0031] The first execution unit is used to construct the synchronous adjustment power based on the trigonometric function value of the phase angle difference;

[0032] The second execution unit is used to input the synchronous regulation power into the active power control loop of the grid-type converter, so as to adjust the output frequency of the grid-type converter based on the synchronous regulation power through the active power control loop, so that the bus voltage is synchronized with the grid voltage.

[0033] Optionally, in the aforementioned apparatus, the first computing unit includes:

[0034] Obtain the sub-unit, used to obtain the virtual impedance;

[0035] An execution subunit is used to vectorize the grid voltage and the bus voltage to obtain the grid voltage vector and the bus voltage vector;

[0036] The calculation subunit is used to calculate the virtual current based on the ratio of the vector difference between the bus voltage vector and the grid voltage vector to the virtual impedance.

[0037] A storage medium includes storage instructions, wherein, when the instructions are executed, the device in which the storage medium resides executes the voltage synchronization method described above.

[0038] An electronic device includes a memory and one or more instructions, wherein one or more instructions are stored in the memory and configured to be executed by one or more processors using the voltage synchronization method described above.

[0039] This application provides a voltage synchronization method, apparatus, storage medium, and electronic device. The method is applied to a power conversion system, which includes a grid-type converter and an AC bus. The output terminal of the grid-type converter is connected to the AC bus, and the AC bus is connected to the power grid via a grid-connected switch. The method includes: acquiring the bus voltage of the AC bus and the grid voltage; calculating a virtual current based on the bus voltage and the grid voltage; calculating a virtual output power based on the bus voltage and the virtual current; determining a trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage; constructing a synchronous regulation power based on the trigonometric function value of the phase angle difference; and inputting the synchronous regulation power into the active power control loop of the grid-type converter to adjust the output frequency of the grid-type converter based on the synchronous regulation power, thereby synchronizing the bus voltage with the grid voltage. This application effectively suppresses repeated frequency fluctuations during the synchronization process by constructing a synchronous regulation power proportional to the phase angle difference and directly introducing it into the active power control loop. Meanwhile, this method eliminates the need for phase-locked loops and PI controllers, significantly reducing the complexity of control parameter tuning. Furthermore, by limiting the synchronous regulation power amplitude based on frequency fluctuation constraints, the speed and accuracy of the voltage synchronization process are ensured, improving the reliability of microgrid grid-connected switching. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0041] Figure 1 A flowchart of a voltage synchronization method provided in this application;

[0042] Figure 2 This application provides a structural example diagram of a power conversion system.

[0043] Figure 3 An example graph illustrating the relationship between virtual output power and phase angle difference is provided in this application.

[0044] Figure 4 A schematic diagram of a voltage synchronization control process provided in this application;

[0045] Figure 5 An example diagram of the variation curves of bus angular frequency increment and phase angle difference provided in this application;

[0046] Figure 6A schematic diagram of the structure of a voltage synchronization device provided in this application;

[0047] Figure 7 This is a schematic diagram of the structure of an electronic device provided in this application. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] This application provides a voltage synchronization method that can be applied to a power conversion system. The power conversion system includes a grid-type converter and an AC bus. The output terminal of the grid-type converter is connected to the AC bus. The flowchart of the method is shown below. Figure 1 As shown, it specifically includes:

[0051] S101: Collect the bus voltage of the AC bus and the grid voltage of the power grid.

[0052] In this embodiment, bus voltage refers to the voltage at the AC bus, and grid voltage refers to the voltage on the public power grid side. In practice, voltage sensors, such as three-phase voltage sensors, can be installed on both sides of the grid-connected switch to collect the voltage values ​​on both sides in real time.

[0053] In some embodiments, such as Figure 2 As shown, the power conversion system may further include a grid-connected converter, and filters corresponding to both the grid-connected converter and the network-connected converter; wherein, This refers to the DC bus voltage of the grid-type converter. This refers to the DC bus voltage of the grid-connected converter; and These are the filter inductors and filter capacitors of a grid-type converter; It is the filter inductor of the mesh converter. It is an AC load within the power conversion system. It is the AC bus voltage. This refers to the grid voltage. Grid-type converters can be used to support AC bus voltage, and they employ a virtual synchronous machine control strategy.

[0054] S102: Calculate the virtual current based on the bus voltage and the grid voltage.

[0055] In an optional embodiment, the calculation of the virtual current based on the bus voltage and the grid voltage may further include:

[0056] Obtain the virtual impedance;

[0057] The grid voltage and the bus voltage are vectorized to obtain the grid voltage vector and the bus voltage vector;

[0058] The virtual current is calculated based on the ratio of the vector difference between the bus voltage vector and the grid voltage vector to the virtual impedance.

[0059] Specifically, the grid voltage is used as the reference voltage, denoted as E∠0; the bus voltage is used as the control object, denoted as U∠0. ,in, To determine the phase angle, a virtual impedance is introduced to calculate the virtual current. The virtual impedance value is taken as the unit resistance. Then the virtual current Represented as:

[0060] (1)

[0061] S103: Calculate the virtual output power based on the bus voltage and the virtual current.

[0062] In this embodiment, the virtual output power is a complex power calculated based on the bus voltage and virtual current. It includes active and reactive components and can be used to extract the phase angle difference information between the two voltages.

[0063] In an optional embodiment, calculating the virtual output power based on the bus voltage and the virtual current includes:

[0064] The virtual output power is calculated based on the product of the complex conjugate of the bus voltage and the virtual current.

[0065] Specifically, the virtual output power is expressed as:

[0066] (2)

[0067] S104: Determine the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the virtual output power and the amplitude of the bus voltage.

[0068] In this embodiment, the phase angle difference refers to the angle between the bus voltage vector and the grid voltage vector, and the sine or cosine value of this angle can be used for subsequent synchronization adjustment.

[0069] In an optional embodiment, determining the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage includes:

[0070] The product of the virtual reactive power in the virtual output power and the virtual impedance is divided by the product of the square of the amplitude of the bus voltage and a preset coefficient to calculate the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage.

[0071] The specific method for calculating the trigonometric functions of phase angle difference is as follows:

[0072] First, for the virtual output power, by taking its real and imaginary parts respectively, the virtual active power output power and virtual reactive power output power can be calculated as follows:

[0073] (3)

[0074] (4)

[0075] in, This is the virtual active power output. This refers to virtual reactive power output; such as Figure 3 As shown, this application provides and As shown in the example graph of the phase angle difference curve, the virtual active power output exhibits an even function characteristic, making it impossible to distinguish whether the phase angle is leading or lagging. The virtual reactive power output exhibits an odd function characteristic, making it possible to distinguish whether the phase angle is leading or lagging.

[0076] Optionally, the preset coefficient can be set according to actual needs, for example, it can be 3, corresponding to three-phase numbers.

[0077] Next, to maintain a constant voltage in the power conversion system, secondary control can be introduced to maintain the voltage amplitude. Here, assuming that the voltage amplitude of the power conversion system is equal to the voltage amplitude of the grid, the trigonometric function of the phase angle difference can be obtained as follows:

[0078] (5)

[0079] (6)

[0080] S105: Construct synchronous regulating power based on the trigonometric function value of the phase angle difference.

[0081] In an optional embodiment, constructing the synchronous regulation power based on the trigonometric function value of the phase angle difference includes:

[0082] The synchronous adjustment power is obtained by multiplying the trigonometric function value of the phase angle difference with the preset maximum value of the synchronous adjustment power.

[0083] The maximum amplitude of the synchronous regulation power can be designed based on the maximum allowable frequency fluctuation range of the system. For example, if the frequency fluctuation is limited to no more than ±0.5Hz, the maximum amplitude must meet certain constraints. This maximum amplitude ensures smooth frequency changes during synchronization and avoids drastic fluctuations. By multiplying the sine value by the maximum amplitude, the magnitude of the synchronous regulation power is made proportional to the sine value of the current phase angle difference, thereby achieving closed-loop regulation.

[0084] S106: Input the synchronous regulation power into the active power control loop of the grid-type converter, so that the output frequency of the grid-type converter is adjusted by the active power control loop based on the synchronous regulation power, so that the bus voltage is synchronized with the grid voltage.

[0085] Grid-type converters typically employ a virtual synchronous machine control strategy, where the active power loop input includes an active power reference value and the actual output power. This application introduces synchronous regulation power into this loop, effectively regulating the reference value and thus changing the converter's output frequency.

[0086] In one embodiment provided in this application, based on the above-described scheme, optionally, the step of inputting the synchronous regulation power into the active power control loop of the grid-type converter, so as to adjust the output frequency of the grid-type converter based on the synchronous regulation power through the active power control loop, includes:

[0087] The synchronous regulation power is input into the active power control loop as a compensation amount for the active power reference value of the grid-type converter.

[0088] The active power control loop generates an angular frequency increment based on the synchronously regulated power.

[0089] The output frequency of the grid converter is adjusted based on the angular frequency increment.

[0090] Specifically, the synchronous regulating power is subtracted from or added to the active power reference value, causing a shift in the active power loop reference value. This shift, in turn, generates an angular frequency increment through the rotor motion equation of the virtual synchronizer. This angular frequency increment is superimposed on the rated angular frequency to obtain the actual output angular frequency of the converter. Since the direction of the synchronous regulating power is related to the phase angle difference, the frequency regulation direction always tends to reduce the phase angle difference. When the phase angle difference gradually decreases to zero, the synchronous regulating power also decreases to zero, the frequency returns to the rated value, and voltage synchronization is completed.

[0091] In this embodiment, the active power loop of the grid-type converter controlled by a virtual synchronous machine has the following characteristics in the s-domain:

[0092] (7)

[0093] in, This refers to the output angular frequency. This is virtual inertia; For the Laplace operator; The active power-frequency droop factor; P is the reference value for active power; P is the actual output active power. This is the rated angular frequency.

[0094] During voltage synchronization, the output power P of the grid-type converter remains constant, and equivalent regulation is achieved by introducing synchronous regulation power. This allows for secondary frequency modulation to adjust the bus frequency and achieve phase synchronization.

[0095] See Figure 4 This is a schematic diagram of a voltage synchronization control process provided in this application. After introducing synchronous regulation power, the transfer function of the active power loop becomes:

[0096] (8)

[0097] The resulting angular frequency increment after introducing synchronous adjustment power is expressed as:

[0098] (9)

[0099] To ensure that the bus voltage frequency does not fluctuate drastically during voltage synchronization, the maximum value of the synchronization regulation power is determined by equation (9). The design is as follows:

[0100] During voltage synchronization, if the system frequency fluctuation range is ±0.5Hz, then the amplitude of the maximum synchronous regulation power is... Must meet:

[0101] (10)

[0102] in, This indicates the maximum permissible angular frequency deviation of the system.

[0103] Multiplying the sine value of the phase angle difference, which indicates whether the phase angle is leading or lagging, by the maximum value of the synchronous regulation power calculated by equation (10), we obtain the synchronous regulation power introduced into the active power loop as follows:

[0104] (11)

[0105] In a digitally controlled converter, the bus voltage is collected by a voltage sensor. and grid voltage The virtual reactive power output is calculated as follows:

[0106] (12)

[0107] in, , and Representing the three-phase line voltages respectively, the calculation is as follows:

[0108] (13)

[0109] This represents the first phase voltage in the bus voltage. This represents the second phase voltage in the bus voltage. This represents the third phase voltage in the bus voltage. This represents the voltage of the first phase in the power grid. This represents the second phase voltage in the power grid. This represents the third phase voltage in the power grid.

[0110] The amplitude of the bus voltage is:

[0111] (14)

[0112] The final calculation of the synchronous regulation power introduced by the active power loop for voltage synchronization is as follows:

[0113] (15)

[0114] The curves showing the change in bus angular frequency increment and phase angle difference during the synchronization process, such as... Figure 5 As shown, when the synchronization process is completed, the angular frequency increment also decreases to zero. During the synchronization process, the angular frequency change trend is constant, avoiding the problem of repeated fluctuations.

[0115] In this embodiment, the method utilizes the concept of synchronous power regulation, eliminating the need for a phase-locked loop and an additional PI controller, thus reducing the phase angle jumps and frequency fluctuations present in traditional synchronization methods. By introducing virtual impedance to calculate virtual current and virtual output power, the phase angle difference information is extracted in trigonometric function form, and then the synchronous power regulation is constructed to directly act on the active power loop, achieving fast and accurate voltage synchronization and improving synchronization reliability.

[0116] In summary, the embodiments of this application achieve rapid and smooth voltage synchronization by constructing synchronous power regulation and introducing an active power loop, solving the problems of difficult phase-locked loop parameter tuning and frequency fluctuations during the synchronization process in traditional methods, and improving the grid-connected switching performance of the power conversion system.

[0117] and Figure 1 Corresponding to the method described herein, embodiments of this application also provide a voltage synchronization device, applied to a power conversion system, for use in... Figure 1 The specific implementation of the method is shown in the schematic diagram of the device. Figure 6 As shown, it includes:

[0118] The acquisition unit 601 is used to acquire the bus voltage of the AC bus and the grid voltage of the power grid;

[0119] The first calculation unit 602 is used to calculate the virtual current based on the bus voltage and the grid voltage;

[0120] The second calculation unit 603 is used to calculate the virtual output power based on the bus voltage and the virtual current.

[0121] The determining unit 604 is used to determine the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage;

[0122] The first execution unit 605 is used to construct synchronous adjustment power based on the trigonometric function value of the phase angle difference;

[0123] The second execution unit 606 is used to input the synchronous regulation power into the active power control loop of the grid-type converter, so as to adjust the output frequency of the grid-type converter based on the synchronous regulation power through the active power control loop, so that the bus voltage is synchronized with the grid voltage.

[0124] The specific principles and execution processes of each unit and module in the voltage synchronization device disclosed in the above embodiments of this application are related to... Figure 1 The voltage synchronization method disclosed in the embodiments is the same, and can be found in the corresponding part of the voltage synchronization method provided in the above embodiments of this application, which will not be repeated here.

[0125] This application embodiment also provides a storage medium, which includes stored instructions, wherein, when the instructions are executed, the device where the storage medium is located is controlled to perform the voltage synchronization method described above.

[0126] This application also provides an electronic device, the structural schematic diagram of which is shown below. Figure 7 As shown, it specifically includes a memory 701 and one or more instructions 702, wherein one or more instructions 702 are stored in the memory 701 and are configured to be executed by one or more processors 703 to perform the voltage synchronization method described above.

[0127] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For apparatus embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0128] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0129] For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0130] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0131] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A voltage synchronization method, characterized in that, The method is applied to a power conversion system, which includes a grid-connected converter and an AC bus. The output of the grid-connected converter is connected to the AC bus, and the AC bus is connected to the power grid via a grid-connected switch. Collect the bus voltage of the AC bus and the grid voltage of the power grid; Calculate the virtual current based on the bus voltage and the grid voltage; Calculate the virtual output power based on the bus voltage and the virtual current; Based on the virtual output power and the amplitude of the bus voltage, determine the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage; The synchronous adjustment power is constructed based on the trigonometric function value of the phase angle difference; The synchronous regulation power is input into the active power control loop of the grid converter, so that the output frequency of the grid converter is adjusted by the active power control loop based on the synchronous regulation power, so that the bus voltage is synchronized with the grid voltage.

2. The method according to claim 1, characterized in that, The calculation of the virtual current based on the bus voltage and the grid voltage includes: Obtain the virtual impedance; The grid voltage and the bus voltage are vectorized to obtain the grid voltage vector and the bus voltage vector; The virtual current is calculated based on the ratio of the vector difference between the bus voltage vector and the grid voltage vector to the virtual impedance.

3. The method according to claim 2, characterized in that, The calculation of virtual output power based on the bus voltage and the virtual current includes: The virtual output power is calculated based on the product of the complex conjugate of the bus voltage and the virtual current.

4. The method according to claim 2, characterized in that, The step of determining the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage includes: The product of the virtual reactive power in the virtual output power and the virtual impedance is divided by the product of the square of the amplitude of the bus voltage and a preset coefficient to calculate the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage.

5. The method according to claim 1, characterized in that, The construction of synchronous adjustment power based on the trigonometric function value of the phase angle difference includes: The synchronous adjustment power is obtained by multiplying the trigonometric function value of the phase angle difference with the preset maximum value of the synchronous adjustment power.

6. The method according to claim 1, characterized in that, The step of inputting the synchronous regulation power into the active power control loop of the grid converter, so as to adjust the output frequency of the grid converter based on the synchronous regulation power through the active power control loop, includes: The synchronous regulation power is input into the active power control loop as a compensation amount for the active power reference value of the grid-type converter. The active power control loop generates an angular frequency increment based on the synchronously regulated power. The output frequency of the grid converter is adjusted based on the angular frequency increment.

7. A voltage synchronization device, characterized in that, An application in a power conversion system, the power conversion system including a grid-type converter and an AC bus, wherein the output terminal of the grid-type converter is connected to the AC bus, and the AC bus is connected to the power grid through a grid-connected switch, the device comprising: The acquisition unit is used to acquire the bus voltage of the AC bus and the grid voltage of the power grid; The first calculation unit is used to calculate the virtual current based on the bus voltage and the grid voltage; The second calculation unit is used to calculate the virtual output power based on the bus voltage and the virtual current; The determining unit is used to determine the trigonometric function value of the phase angle difference between the bus voltage and the grid voltage based on the amplitude of the virtual output power and the bus voltage; The first execution unit is used to construct the synchronous adjustment power based on the trigonometric function value of the phase angle difference; The second execution unit is used to input the synchronous regulation power into the active power control loop of the grid-type converter, so as to adjust the output frequency of the grid-type converter based on the synchronous regulation power through the active power control loop, so that the bus voltage is synchronized with the grid voltage.

8. The apparatus according to claim 7, characterized in that, The first computing unit includes: Obtain the sub-unit, used to obtain the virtual impedance; An execution subunit is used to vectorize the grid voltage and the bus voltage to obtain the grid voltage vector and the bus voltage vector; The calculation subunit is used to calculate the virtual current based on the ratio of the vector difference between the bus voltage vector and the grid voltage vector to the virtual impedance.

9. A storage medium, characterized in that, The storage medium includes stored instructions, wherein, when the instructions are executed, the device in which the storage medium is located is controlled to perform the voltage synchronization method as described in any one of claims 1 to 6.

10. An electronic device, characterized in that, It includes a memory, and one or more instructions, wherein one or more instructions are stored in the memory and configured to be executed by one or more processors as described in any one of claims 1 to 6.

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