Harmonic extraction method, controller, power supply device, and storage medium

Abstract

The application provides a harmonic extraction method, a controller, a power supply device and a storage medium. The method is applied to a power supply device connected with an alternating current source, and comprises the following steps: acquiring a voltage signal of the alternating current source, and converting the voltage signal into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system; performing first extraction on the two-dimensional equivalent voltage signal according to a first harmonic extractor determined in advance, to obtain an intermediate harmonic quantity; performing iterative processing on the intermediate harmonic quantity, and performing second extraction on the intermediate harmonic quantity after the iterative processing according to a second harmonic extractor determined in advance, to obtain a target harmonic; wherein the first harmonic extractor is different from the second harmonic extractor, but both the first harmonic extractor and the second harmonic extractor comprise a first parameter A and a second parameter B, the first parameter A and the second parameter B are both frequency parameters of the target harmonic determined in advance, and A 2 +B 2 =1. The application can improve the working reliability of the power supply device.

Description

Technical Field

[0001] This application relates to the field of harmonic compensation technology, and in particular to a harmonic extraction method, controller, power supply device and storage medium. Background Technology

[0002] When single-phase or three-phase power supply equipment is connected to the power grid to supply power to a load, harmonics may be generated. Harmonics affect the normal operation of the power supply equipment, and in severe cases, may cause damage to the equipment, affecting the user's normal power supply and reducing power supply reliability. Harmonic compensation can eliminate this impact; therefore, harmonic extraction and compensation are particularly important.

[0003] Currently, most methods employ passive filters, which are based on the principle of LC filter circuits and use filter capacitors and inductors to filter out harmonics generated by the power grid. However, this method is greatly affected by load impedance and cannot be applied to the full power range. Summary of the Invention

[0004] This application provides a harmonic extraction method, controller, power supply device, and storage medium to address the problem that existing harmonic compensation methods mostly use passive filters, which are greatly affected by load impedance and cannot be applied to the full power range.

[0005] In a first aspect, embodiments of this application provide a harmonic extraction method, applied to a power supply device connected to an AC source, comprising:

[0006] Acquire the voltage signal of the AC source and convert the voltage signal into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system;

[0007] The intermediate harmonic quantity is obtained by extracting the two-dimensional equivalent voltage signal once according to the predetermined first harmonic extractor.

[0008] The intermediate harmonic quantity is iteratively processed, and the intermediate harmonic quantity after iterative processing is extracted a second time according to the pre-determined second harmonic extractor to obtain the target harmonic;

[0009] The first harmonic extractor differs from the second harmonic extractor, but both include a first parameter A and a second parameter B. Both first parameter A and second parameter B are predetermined frequency parameters of the target harmonic, and A... 2 +B 2 =1.

[0010] In one possible approach, the two-dimensional equivalent voltage signal is represented as (x α ,y β The input and output terminals of the first and second harmonic extractors are both two-dimensional parameters. The two-dimensional parameters at the input terminals are represented as (i... α i βThe two-dimensional parameters at the output end are represented as (o α ,o β );

[0011] One of the extractors is represented as follows: Another extractor is represented as:

[0012] In one possible approach, the first harmonic extractor is: The second harmonic extractor is:

[0013] In one possible approach, the frequency parameter of the target harmonic is θ. k The first parameter A = cosθ k The second parameter B = sinθ k .

[0014] In one possible way, θ k =nω k T s T s =1 / f s f s ω represents the sampling frequency. k =2πf k f k Indicates the frequency of the target harmonic.

[0015] In one possible approach, the two-dimensional equivalent voltage signal is represented as (x α ,y β The intermediate harmonic quantity is expressed as

[0016] The expression for iterative processing of intermediate harmonic quantities is:

[0017] X α 1 (n)=X α 1 (n-1)+x α (n)A+x β (n)B

[0018] X β 1 (n)=X β 1 (n-1)+x β (n)Ax α (n)B

[0019] Correspondingly, the expression for secondary extraction of the intermediate harmonic quantities after iterative processing is as follows:

[0020]

[0021] Where n represents the nth signal period, y α (n) represents the α value of the target harmonic in a two-phase stationary coordinate system, y β (n) represents the β coordinate of the target in the two-phase stationary coordinate system, and M represents a preset constant.

[0022] In one possible approach, the two-dimensional equivalent voltage signal is represented as (x α ,y β Before performing a single extraction of the two-dimensional equivalent voltage signal according to a predetermined first harmonic extractor, the harmonic extraction method further includes:

[0023] The two-dimensional equivalent voltage signal is iteratively processed to obtain an iterative two-dimensional equivalent voltage signal;

[0024] Accordingly, the two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor, including:

[0025] The iterative two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor;

[0026] The expression for iterative processing of the two-dimensional equivalent voltage signal is as follows:

[0027] F1(n)=x α (n)-x α (nN)

[0028] F2(n)=x β (n)-x β (nN)

[0029] n represents the nth signal period, N = f s / f k f s f represents the sampling frequency. k The frequency of the target harmonic is represented by (F1(n), F2(n)), and the value of the iterative two-dimensional equivalent voltage signal in the two-phase stationary coordinate system is represented by (F1(n), F2(n)).

[0030] In one possible approach, the voltage signal of the AC source is acquired and converted into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system, including:

[0031] When the voltage of the AC source is a three-phase voltage, the three-phase voltage of the AC source is obtained, and the coordinate transformation of the three-phase voltage is performed to obtain the first equivalent voltage signal and the second equivalent voltage signal of the AC source in a two-phase stationary coordinate system.

[0032] When the voltage of the AC source is a single-phase voltage, the single-phase voltage of the AC source is obtained, and the single-phase voltage is transformed by coordinate transformation to obtain the first equivalent voltage signal and the second equivalent voltage signal of the AC source in a two-phase stationary coordinate system. At this time, when the first equivalent voltage signal is zero, the second equivalent voltage signal is not zero, and when the first equivalent voltage signal is not zero, the second equivalent voltage signal is zero.

[0033] Secondly, embodiments of this application provide a harmonic compensation device, applied to a power supply device connected to an AC source, comprising:

[0034] The signal acquisition module is used to acquire the voltage signal of the AC source and convert the voltage signal into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system.

[0035] The first extraction module is used to extract the two-dimensional equivalent voltage signal once according to the predetermined first harmonic extractor to obtain the intermediate harmonic quantity;

[0036] The second extraction module is used to iteratively process the intermediate harmonic quantity. According to the pre-determined second harmonic extractor, the intermediate harmonic quantity after iterative processing is extracted a second time to obtain the target harmonic.

[0037] The first harmonic extractor differs from the second harmonic extractor, but both include a first parameter A and a second parameter B. Both first parameter A and second parameter B are predetermined frequency parameters of the target harmonic, and A... 2 +B 2 =1.

[0038] Thirdly, embodiments of this application provide a controller, including a memory and a processor. The memory stores a computer program that can run on the processor. When the processor executes the computer program, it implements the steps of the harmonic extraction method as described in the first aspect or any possible implementation of the first aspect.

[0039] Fourthly, embodiments of this application provide a power supply device, including a controller as described in the third aspect.

[0040] Fifthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the harmonic extraction method as described in the first aspect or any possible implementation of the first aspect.

[0041] This application provides a harmonic extraction method, controller, power supply device, and storage medium. The method converts the voltage signal of an AC source into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system for easier calculation. Then, a first harmonic extractor extracts the intermediate harmonics from this two-dimensional equivalent voltage signal. Finally, the intermediate harmonics are iteratively processed, and a second harmonic extractor extracts the iteratively processed intermediate harmonics a second time to obtain the target harmonics. Both the first and second harmonic extractors include the same first parameter A and second parameter B, and these two parameters are correlated. This application eliminates the need for additional passive filtering devices, is unaffected by load impedance, is applicable across the entire power range, and allows for targeted compensation after obtaining the target harmonics. This significantly reduces the impact of harmonics on the power supply device, improving power supply reliability and the operational reliability of the power supply device. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application, 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating the implementation of the harmonic extraction method provided in the embodiments of this application;

[0044] Figure 2 This is a block diagram of a harmonic compensation algorithm provided in an embodiment of this application;

[0045] Figure 3 This is a schematic diagram of the structure of the harmonic compensation device provided in the embodiments of this application;

[0046] Figure 4 This is a schematic diagram of the controller provided in an embodiment of this application. Detailed Implementation

[0047] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.

[0049] After being connected to the power grid, power supply equipment is used to supply power to loads. During the connection process, harmonics are often generated. These harmonics not only pollute the power grid but can also damage the power supply equipment, affecting its lifespan and power supply reliability, and consequently impacting the user's load operation.

[0050] To address the aforementioned issues, this application provides a harmonic extraction method that accurately extracts target harmonics through calculation, and then compensates for the target harmonics to avoid their impact on power supply and improve power supply reliability.

[0051] See Figure 1 The diagram illustrates the implementation flowchart of the harmonic extraction method provided in the embodiments of this application. Figure 1 As shown, a harmonic extraction method is applied to a power supply device connected to an AC source and may include S101 to S103.

[0052] S101 acquires the voltage signal of the AC source and converts the voltage signal into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system.

[0053] In the embodiments of this application, after acquiring the voltage signal of the AC source, the voltage signal can be transformed into a coordinate system, such as by Clark transformation (abc-αβ) or PARK transformation, to convert the voltage signal from a three-phase coordinate system into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system. The AC source can be a power grid or a current source that outputs AC power.

[0054] The power supply equipment draws power from an AC source, which can provide single-phase or three-phase power, and the voltage of the AC source can include single-phase voltage or three-phase voltage.

[0055] When the voltage of the AC source is a three-phase voltage, the two-dimensional equivalent voltage signal in the two-phase stationary coordinate system is represented as (x α ,x β ).

[0056] When the voltage of the AC source is a single-phase voltage, the two-dimensional equivalent voltage signal in the two-phase stationary coordinate system is represented as (x α (,0) or (0,x) β ).

[0057] The harmonic extraction method provided in this application can be applied to single-phase voltage or three-phase voltage, with a wider range of applications and strong compatibility.

[0058] S102, the two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor to obtain the intermediate harmonic quantity.

[0059] The first harmonic extractor can be pre-constructed based on the frequency parameters of the target harmonic. Both the input and output of the first harmonic extractor can be two-dimensional parameters. That is, after one extraction by the first harmonic extractor from the two-dimensional equivalent voltage signal, the intermediate harmonic quantity can be obtained, and the intermediate harmonic quantity is a two-dimensional parameter.

[0060] In the embodiments of this application, the target harmonic refers to the harmonic to be extracted. The order of the target harmonic can be predetermined, and it is a harmonic with a higher degree of harm. Generally speaking, lower-order harmonics are more harmful than higher-order harmonics, and odd-order harmonics are more harmful than even-order harmonics. Therefore, the target harmonic can be the third, fifth, or seventh harmonic, and can be set according to the actual situation. The target harmonic can be a harmonic in the entire frequency band.

[0061] S103, perform iterative processing on the intermediate harmonic quantity, and extract the intermediate harmonic quantity after iterative processing a second time according to the predetermined second harmonic extractor to obtain the target harmonic.

[0062] The first harmonic extractor differs from the second harmonic extractor, but both include a first parameter A and a second parameter B. Both first parameter A and second parameter B are predetermined frequency parameters of the target harmonic, and A... 2 +B 2 =1.

[0063] The second harmonic extractor can be pre-constructed based on the frequency parameters of the target harmonic. Both the input and output of the second harmonic extractor can be two-dimensional parameters.

[0064] In the embodiments of this application, after iterative processing of the intermediate harmonic quantity, the iteratively processed intermediate harmonic quantity can be obtained. The iteratively processed intermediate harmonic quantity is then extracted a second time by the second harmonic extractor to obtain the final target harmonic, which is a two-dimensional signal with two phases degraded to the coordinate system.

[0065] In embodiments of this application, the frequency parameters of the target harmonic may include a first parameter A and a second parameter B, wherein the first parameter A and the second parameter B satisfy the following relationship: A 2 +B 2 =1. Both the first harmonic extractor and the second harmonic extractor can include the first parameter A and the second parameter B; however, the first harmonic extractor and the second harmonic extractor are not the same.

[0066] This application's embodiments construct a first harmonic extractor and a second harmonic extractor based on the frequency parameters of the target harmonic. By sequentially performing primary and secondary extractions on the two-dimensional equivalent voltage signal, the target harmonic can be accurately extracted, significantly reducing the difficulty of constructing the first and second harmonic extractors. Furthermore, no additional passive filtering devices are required, making it suitable for harmonic extractors across the entire power band. This facilitates subsequent accurate compensation for the target harmonic, reducing the impact of harmonics on power supply equipment and improving the power supply reliability of AC sources and the operational reliability of power supply equipment.

[0067] In some embodiments of this application, the two-dimensional equivalent voltage signal is represented as (x α ,y β The input and output terminals of the first and second harmonic extractors are both two-dimensional parameters. The two-dimensional parameters at the input terminals are represented as (i... α i β The two-dimensional parameters at the output end are represented as (o α ,o β );

[0068] One of the extractors is represented as follows: Another extractor is represented as:

[0069] In the embodiments of this application, the first harmonic extractor and the second harmonic extractor are different.

[0070] The first harmonic extractor is At that time, the second harmonic extractor can be

[0071] The first harmonic extractor is At that time, the second harmonic extractor can be

[0072] In the embodiments of this application, the frequency parameter of the target harmonic is θ. k The first parameter A = cosθ k The second parameter B = sinθ k Where k can represent the kth harmonic.

[0073] Optionally, the first harmonic extractor is And the second harmonic extractor is

[0074] Alternatively, the first harmonic extractor is And the second harmonic extractor is

[0075] In the embodiments of this application, θ k =nω k Ts T s =1 / f s f s ω represents the sampling frequency. k =2πf k f k Indicates the frequency of the target harmonic.

[0076] Where, θ k =knω0T s ω0 represents the fundamental frequency. When k = 1, the target harmonic extracted by the harmonic extraction method provided in this application is the fundamental frequency. That is, this application can extract both the fundamental frequency and harmonics, has a wide range of applications, and strong compatibility.

[0077] Specifically, the first parameter A = cos(nω) k T s The second parameter B = sin(nω) k T s ).

[0078] In the embodiments of this application, the first harmonic extractor is represented as: The second harmonic extractor is represented as:

[0079] The embodiments of this application can accurately extract target harmonics by constructing a first harmonic extractor and a second harmonic extractor, thereby improving the reliability of harmonic extraction.

[0080] In some embodiments of this application, the two-dimensional equivalent voltage signal is represented as (x α ,y β The intermediate harmonic quantity is expressed as

[0081] The expression for iterative processing of intermediate harmonic quantities is:

[0082] X α 1 (n)=X α 1 (n-1)+x α (n)A+x β (n)B

[0083] X β 1 (n)=X β 1 (n-1)+x β (n)Ax α (n)B

[0084] Correspondingly, the expression for secondary extraction of the intermediate harmonic quantities after iterative processing is as follows:

[0085]

[0086] Where n represents the nth signal period, y α (n) represents the α value of the target harmonic in a two-phase stationary coordinate system, y β (n) represents the β coordinate of the target in the two-phase stationary coordinate system, and M represents a preset constant.

[0087] In the embodiments of this application, the preset constants M = 1 / N and N = f s / f k f s f represents the sampling frequency. k Indicates the frequency of the target harmonic.

[0088] For example, the first parameter A = cos(nω) k T s The second parameter B = sin(nω) k T s The expression for iterative processing of intermediate harmonic quantities can be:

[0089] X α 1 (n)=X α 1 (n-1)+x α (n)cos(nω k T s )+x β (n)sin(nω k T s )

[0090] X β 1 (n)=X β 1 (n-1)+x β (n)cos(nω k T s )-x α (n)sin(nω k T s )

[0091] Correspondingly, the expression for secondary extraction of the intermediate harmonic quantities after iterative processing can be:

[0092]

[0093] The embodiments of this application can accurately obtain the two-dimensional value of the target harmonic by sequentially extracting the two-dimensional equivalent voltage signal through one extraction, iterative processing and two extractions, which is beneficial for the accurate compensation of the target harmonic and improves the working reliability of the power supply equipment.

[0094] In some embodiments of this application, the two-dimensional equivalent voltage signal is represented as (x α ,y β Before performing a single extraction of the two-dimensional equivalent voltage signal according to a predetermined first harmonic extractor, the harmonic extraction method further includes:

[0095] The two-dimensional equivalent voltage signal is iteratively processed to obtain an iterative two-dimensional equivalent voltage signal;

[0096] Accordingly, the two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor, including:

[0097] The iterative two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor;

[0098] The expression for iterative processing of the two-dimensional equivalent voltage signal is as follows:

[0099] F1(n)=x α (n)-x α (nN)

[0100] F2(n)=x β (n)-x β (nN)

[0101] n represents the nth signal period, N = f s / f k f s f represents the sampling frequency. k The frequency of the target harmonic is represented by (F1(n), F2(n)), and the value of the iterative two-dimensional equivalent voltage signal in the two-phase stationary coordinate system is represented by (F1(n), F2(n)).

[0102] For example, the first parameter A = cos(nω) k T s The second parameter B = sin(nω) k T s The two-dimensional equivalent voltage signal is represented as (x α ,y β The expression for extracting the target harmonics can be expressed as:

[0103]

[0104] X α 1 (n)=X α 1 (n-1)+[x α (n)-x α (nN)]cos(nω k T s )+[xβ (n)-x β (nN)]sin(nω k T s )

[0105] X β 1 (n)=X β 1 (n-1)+[x β (n)-x β (nN)]cos(nω k T s )-[x α (n)-x α (nN)]sin(nω k T s )

[0106] When the harmonic frequency to be extracted changes, a first parameter A and a second parameter B corresponding one-to-one with the target harmonic can be established based on the changed frequency. Then, a first extraction and a second extraction are performed using the first and second harmonic extractors to obtain the target harmonic, and then harmonic compensation is performed on the target harmonic.

[0107] That is, it is necessary to extract the kth harmonic of the current input voltage signal, determine the corresponding first parameter A and second parameter B according to the harmonic frequency k·f of the kth harmonic, and finally combine the target extraction parameters to extract the kth harmonic.

[0108] For example, Figure 2 This is a block diagram of a harmonic compensation algorithm provided in an embodiment of this application. For example... Figure 2 As shown, taking a three-phase system as an example, the harmonic extraction process can be as follows:

[0109] The three-phase voltage of the AC source is subjected to Clark transformation, converting the voltage from a three-phase coordinate system to a two-dimensional equivalent voltage signal (x) in a two-phase stationary coordinate system. α (n),x β (n)).

[0110] The first parameter A = cos(nω) is determined based on the frequency of the kth harmonic. k T s The second parameter B = sin(nω) k T s ), thereby constructing the first harmonic extractor and the second harmonic extractor.

[0111] The two-dimensional equivalent voltage signal is iteratively processed to obtain an iterative two-dimensional equivalent voltage signal, which is then input into the first harmonic extractor for extraction to obtain the intermediate harmonic quantity.

[0112] The intermediate harmonic quantity is iteratively processed, and the iterated intermediate harmonic quantity is input into the second harmonic extractor for secondary extraction. The two-dimensional signal after secondary extraction is multiplied by the corresponding preset constant M to finally obtain the kth harmonic to be extracted.

[0113] Harmonic compensation is performed on the extracted k-th harmonic to avoid harmonics affecting the operation of power supply equipment.

[0114] In some embodiments of this application, acquiring the voltage signal of an AC source and converting the voltage signal into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system includes:

[0115] When the voltage of the AC source is a three-phase voltage, the three-phase voltage of the AC source is obtained, and the coordinate transformation of the three-phase voltage is performed to obtain the first equivalent voltage signal and the second equivalent voltage signal of the AC source in a two-phase stationary coordinate system.

[0116] When the voltage of the AC source is a single-phase voltage, the single-phase voltage of the AC source is obtained, and the single-phase voltage is transformed by coordinate transformation to obtain the first equivalent voltage signal and the second equivalent voltage signal of the AC source in a two-phase stationary coordinate system. At this time, when the first equivalent voltage signal is zero, the second equivalent voltage signal is not zero, and when the first equivalent voltage signal is not zero, the second equivalent voltage signal is zero.

[0117] The harmonic extraction method provided in this application can select the frequency of single-phase or three-phase voltage, accurately extract specific harmonics, and completely filter out other harmonic components. By setting different filtering parameters online, the frequency adaptive process of the digital filter can be realized. The harmonic extraction method provided in this application can perform zero steady-state error tracking of specific harmonic components in the control command, and has zero gain for other integer multiple frequency components in the control command, achieving complete suppression. It is particularly suitable for applications such as fundamental phase-locked loop, positive and negative sequence extraction of feedforward signals, and high and low voltage ride-through detection.

[0118] In embodiments of this application, after obtaining the target harmonic, the harmonic extraction method may further include: generating a corresponding compensation signal for the target harmonic, and compensating the target harmonic according to the compensation signal.

[0119] The compensation process may include:

[0120] Determine whether the target harmonic exceeds the preset fluctuation range.

[0121] When the target harmonic exceeds the preset fluctuation range, harmonic compensation is performed on the target harmonic.

[0122] When the target harmonic does not exceed the preset fluctuation range, no harmonic compensation is performed on the target harmonic.

[0123] If the target harmonic exceeds the preset fluctuation range, it indicates that the target harmonic has a significant impact on the power supply equipment. In this case, harmonic compensation can reduce the impact of the target harmonic and ensure the reliability of the power supply equipment.

[0124] If the target harmonic does not exceed the preset fluctuation range, it indicates that the target harmonic has little or no impact on the operation of the power supply equipment. In this case, there is no need to compensate for the target harmonic, and the harmonic compensation frequency can be reduced to avoid frequent harmonic compensation.

[0125] In the embodiments of this application, all order harmonics may correspond to the same preset fluctuation range, or each order harmonic may correspond to a preset fluctuation range. The preset fluctuation range may be determined in advance through experiments based on actual conditions.

[0126] This application embodiment determines whether to activate harmonic compensation based on whether the target harmonic exceeds a preset fluctuation range. This can reduce the harmonic compensation frequency and avoid frequent compensation while ensuring the normal operation of the power supply equipment.

[0127] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0128] The following are device embodiments of this application. For details not described in detail, please refer to the corresponding method embodiments described above.

[0129] Figure 3 A schematic diagram of the harmonic compensation device provided in an embodiment of this application is shown. For ease of explanation, only the parts related to the embodiment of this application are shown, and are described in detail below:

[0130] like Figure 3 As shown, the harmonic compensation device 20, applied to a power supply device connected to an AC source, may include:

[0131] The signal acquisition module 201 is used to acquire the voltage signal of the AC source and convert the voltage signal into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system.

[0132] The first extraction module 202 is used to extract the two-dimensional equivalent voltage signal once according to the predetermined first harmonic extractor to obtain the intermediate harmonic quantity;

[0133] The second extraction module 203 is used to iteratively process the intermediate harmonic quantity, and to extract the intermediate harmonic quantity after iterative processing a second time according to the predetermined second harmonic extractor to obtain the target harmonic.

[0134] The first harmonic extractor differs from the second harmonic extractor, but both include a first parameter A and a second parameter B. Both first parameter A and second parameter B are predetermined frequency parameters of the target harmonic, and A... 2 +B 2 =1.

[0135] In some embodiments of this application, the two-dimensional equivalent voltage signal is represented as (x α ,y β The input and output terminals of the first and second harmonic extractors are both two-dimensional parameters. The two-dimensional parameters at the input terminals are represented as (i... α i β The two-dimensional parameters at the output end are represented as (o α ,o β );

[0136] One of the extractors is represented as follows: Another extractor is represented as:

[0137] In some embodiments of this application, the first harmonic extractor is: The second harmonic extractor is:

[0138] In some embodiments of this application, the frequency parameter of the target harmonic is θ. k The first parameter A = cosθ k The second parameter B = sinθ k .

[0139] In some embodiments of this application, θ k =nω k T s T s =1 / f s f s ω represents the sampling frequency. k =2πf k f k Indicates the frequency of the target harmonic.

[0140] In some embodiments of this application, the two-dimensional equivalent voltage signal is represented as (x α ,y β The intermediate harmonic quantity is expressed as

[0141] The expression for iterative processing of intermediate harmonic quantities is:

[0142] X α 1 (n)=X α 1 (n-1)+xα (n)A+x β (n)B

[0143] X β 1 (n)=X β 1 (n-1)+x β (n)Ax α (n)B

[0144] Correspondingly, the expression for secondary extraction of the intermediate harmonic quantities after iterative processing is as follows:

[0145]

[0146] Where n represents the nth signal period, y α (n) represents the α value of the target harmonic in a two-phase stationary coordinate system, y β (n) represents the β coordinate of the target in the two-phase stationary coordinate system, and M represents a preset constant.

[0147] In some embodiments of this application, the two-dimensional equivalent voltage signal is represented as (x α ,y β The harmonic compensation device 20 may further include:

[0148] The processing module is used to iteratively process the two-dimensional equivalent voltage signal before extracting it once according to the predetermined first harmonic extractor, so as to obtain an iterative two-dimensional equivalent voltage signal.

[0149] Accordingly, the two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor, including:

[0150] The iterative two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor;

[0151] The expression for iterative processing of the two-dimensional equivalent voltage signal is as follows:

[0152] F1(n)=x α (n)-x α (nN)

[0153] F2(n)=x β (n)-x β (nN)

[0154] n represents the nth signal period, N = f s / f k f s f represents the sampling frequency. kThe frequency of the target harmonic is represented by (F1(n), F2(n)), and the value of the iterative two-dimensional equivalent voltage signal in the two-phase stationary coordinate system is represented by (F1(n), F2(n)).

[0155] In some embodiments of this application, the signal acquisition module 201 is further configured to:

[0156] When the voltage of the AC source is a three-phase voltage, the three-phase voltage of the AC source is obtained, and the coordinate transformation of the three-phase voltage is performed to obtain the first equivalent voltage signal and the second equivalent voltage signal of the AC source in a two-phase stationary coordinate system.

[0157] When the voltage of the AC source is a single-phase voltage, the single-phase voltage of the AC source is obtained, and the single-phase voltage is transformed by coordinate transformation to obtain the first equivalent voltage signal and the second equivalent voltage signal of the AC source in a two-phase stationary coordinate system. At this time, when the first equivalent voltage signal is zero, the second equivalent voltage signal is not zero, and when the first equivalent voltage signal is not zero, the second equivalent voltage signal is zero.

[0158] Figure 4 This is a schematic diagram of the controller provided in an embodiment of this application. Figure 4 As shown, the controller 30 in this embodiment includes a processor 300 and a memory 301, wherein the memory 301 stores a computer program 302 that can run on the processor 300. When the processor 300 executes the computer program 302, it implements the steps in the various harmonic extraction method embodiments described above. Alternatively, when the processor 300 executes the computer program 302, it implements the functions of each module / unit in the various device embodiments described above.

[0159] For example, computer program 302 may be divided into one or more modules / units, one or more of which are stored in memory 301 and executed by processor 300 to complete this application. One or more modules / units may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of computer program 302 in controller 30.

[0160] The controller 30 may be a control chip, a microcontroller, etc. The controller 30 may include, but is not limited to, a processor 300 and a memory 301. Those skilled in the art will understand that... Figure 4 This is merely an example of controller 30 and does not constitute a limitation on controller 30. It may include more or fewer components than shown, or combine certain components, or different components. For example, the controller may also include input / output devices, network access devices, buses, etc.

[0161] The processor 300 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0162] The memory 301 can be an internal storage unit of the controller 30, such as a hard disk or RAM of the controller 30. The memory 301 can also be an external storage device of the controller 30, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the controller 30. Furthermore, the memory 301 can include both internal and external storage units of the controller 30. The memory 301 is used to store computer programs and other programs and data required by the controller. The memory 301 can also be used to temporarily store data that has been output or will be output.

[0163] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0164] This application embodiment also provides a power supply device, including the controller 30 as described above. The power supply device can be a single-phase uninterruptible power supply or a three-phase uninterruptible power supply.

[0165] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0166] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0167] In the embodiments provided in this application, it should be understood that the disclosed devices / controllers and methods can be implemented in other ways. For example, the device / controller embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0168] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0169] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0170] If an integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various harmonic extraction method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0171] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method of harmonic extraction, characterized by, The application is applied to a power supply device connected with an AC source, comprising: a voltage signal of the AC source is acquired and converted into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system; the two-dimensional equivalent voltage signal is extracted once according to a predetermined first harmonic extractor to obtain an intermediate harmonic quantity; the intermediate harmonic quantity is iteratively processed, and the iteratively processed intermediate harmonic quantity is extracted twice according to a predetermined second harmonic extractor to obtain a target harmonic; Wherein, the first harmonic extractor is different from the second harmonic extractor, but both include a first parameter A and a second parameter B, the first parameter A and the second parameter B are both frequency parameters of a predetermined target harmonic, and A 2 +B 2 =1; the frequency parameter of the target harmonic is , the first parameter , and the second parameter ; The two-dimensional equivalent voltage signal is represented as The input and output of the first and second harmonic extractors are both two-dimensional parameters, wherein the two-dimensional parameter of the input is represented as The two-dimensional parameter of the output is represented as ; One of the extractors is represented as: and the other extractor is represented as: ; The intermediate harmonic amount is expressed as ; the expression for iteratively processing the intermediate harmonic quantity is: the expression for extracting the iteratively processed intermediate harmonic quantity twice is: wherein n represents the nth signal period, represents the target harmonic in the two-phase stationary coordinate system value, represents the target in the two-phase stationary coordinate system coordinate, M represents a preset constant.

2. The harmonic extraction method of claim 1, wherein, The first harmonic extractor is: The second harmonic extractor is: .

3. The harmonic extraction method of claim 1, wherein, , , denotes the sampling frequency, , denotes the frequency of the target harmonic.

4. The harmonic extraction method of claim 1, wherein, The two-dimensional equivalent voltage signal is represented as Before the two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor, the harmonic extraction method further comprises: the two-dimensional equivalent voltage signal is iteratively processed to obtain an iteratively processed two-dimensional equivalent voltage signal; correspondingly, the two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor, comprising: the iteratively processed two-dimensional equivalent voltage signal is extracted once according to the predetermined first harmonic extractor; the expression for iteratively processing the two-dimensional equivalent voltage signal is: n denotes the n-th signal period, N denotes the sampling frequency, denotes the frequency of the target harmonic, denotes the value of the iterated two-dimensional equivalent voltage signal in the two-phase stationary coordinate system.​​​ 5. The method of claim 1, wherein, the voltage signal of the AC source is acquired and converted into a two-dimensional equivalent voltage signal in a two-phase stationary coordinate system, comprising: when the voltage of the AC source is a three-phase voltage, a three-phase voltage of the AC source is acquired, and the three-phase voltage is coordinate-transformed to obtain a first equivalent voltage signal and a second equivalent voltage signal of the AC source in the two-phase stationary coordinate system; when the voltage of the AC source is a single-phase voltage, a single-phase voltage of the AC source is acquired, and the single-phase voltage is coordinate-transformed to obtain a first equivalent voltage signal and a second equivalent voltage signal of the AC source in the two-phase stationary coordinate system, at this time, the second equivalent voltage signal is not zero when the first equivalent voltage signal is zero, and the second equivalent voltage signal is zero when the first equivalent voltage signal is not zero.

6. A controller comprising a memory and a processor, the memory having stored therein a computer program executable on the processor, characterized in that, The processor executes the computer program to realize the steps of the harmonic extraction method according to any one of claims 1 to 5.

7. A power supply device characterized by comprising: The controller according to claim 6 is included.

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