Harmonic angle compensation method based on multiple calculation modules

Abstract

The invention provides a harmonic angle compensation method based on multiple calculation modules, a main calculation module samples a load current and then calculates to obtain load harmonic current data and a harmonic compensation angle, the harmonic compensation angle covers time delay in receiving and sending processes, an auxiliary calculation module decomposes the load harmonic current data into a plurality of forms, and the auxiliary calculation module calculates the load harmonic current data according to the plurality of forms. And the main calculation module is used for receiving the harmonic compensation angle and performing compensation operation on the load harmonic current data in a complex form according to the harmonic compensation angle to obtain harmonic modulation wave instructions, and generating a total harmonic compensation instruction according to a plurality of harmonic modulation wave instructions. According to the invention, through the time delay compensation technology, the in-phase compensation of harmonic waves is realized, and the compensation rate of each harmonic wave is improved while the steps are simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of harmonic compensation, and particularly to a harmonic angle compensation method based on multiple calculation modules. Background Art

[0002] With the popularization of new energy technologies and the concept of microgrids, while bringing more convenient clean energy to people, it also poses challenges to the power system. The power quality problems caused by the electrification of the power system need to attract wide attention. Among them, harmonic pollution is an important aspect that needs to be concerned about improving power quality. To solve the problem of harmonic pollution, harmonic compensation is required. The realization of the harmonic compensation function requires simultaneous compensation of multiple harmonics, which means that multiple digital signal processors (DSPs) need to complete calculations simultaneously and then send out the calculated modulation waves simultaneously.

[0003] During the process of transmitting data between different digital signal processors, there must be delays, and such delays will greatly weaken the high-order harmonic compensation effect. Summary of the Invention

[0004] To solve the above problems, a harmonic angle compensation method based on multiple calculation modules provided by the present invention adopts the following technical solutions:

[0005] A harmonic angle compensation method based on multiple calculation modules includes a main calculation module and multiple auxiliary calculation modules. The main calculation module samples the load current and then generates a harmonic compensation angle and transmits it to the auxiliary calculation modules. The auxiliary calculation modules perform compensation calculations on the load current and then transmit the obtained harmonic modulation wave instructions to the main calculation module. The main calculation module generates a total harmonic compensation instruction according to multiple harmonic modulation wave instructions. It further includes:

[0006] Step S1: The main calculation module samples the load current to obtain a sampling value, and performs Fourier transform on the sampling value and then calculates the load harmonic current data and the harmonic compensation angle.

[0007] Step S2: The auxiliary calculation modules receive the load harmonic current data obtained by the main calculation module, and decompose the load harmonic current data into a complex form with a real part and an imaginary part.

[0008] Step S3: The auxiliary calculation modules receive the harmonic compensation angle calculated by the main calculation module, and perform compensation operations on the complex-form load harmonic current data according to the harmonic compensation angle.

[0009] Step S4: The auxiliary calculation modules generate harmonic modulation wave instructions according to the load harmonic current data that has undergone compensation operations.

[0010] Step S5: The auxiliary calculation module writes the generated harmonic modulation wave instruction back to the main calculation module, and the main calculation module generates a total harmonic compensation instruction according to the multiple harmonic modulation wave instructions transmitted by the multiple auxiliary calculation modules.

[0011] The implementation method may include any or all of the following features.

[0012] Further, step S3 further includes step S31: The auxiliary calculation module receives the harmonic compensation angle calculated by the main calculation module and calculates a compensation factor according to the harmonic compensation angle.

[0013] Further, the compensation factor k is calculated according to the harmonic compensation angle θ 1 and the compensation factor k 2 The formula is as follows:

[0014]

[0015]

[0016] Further, step S3 further includes step S32: The auxiliary calculation module performs a compensation operation on the complex load harmonic current data according to the compensation factor to obtain the compensated real part and the compensated imaginary part.

[0017] Further, the relevant calculation formula for the compensation operation is as follows:

[0018] real * = real * k 1 + imag * k 2 ,

[0019] imag * = imag * k 1 + real * k 2 .

[0020] Where real * is the compensated real part, imag * is the compensated imaginary part, real is the real part of the load harmonic current data before the compensation operation, and imag is the imaginary part of the load harmonic current data before the compensation operation.

[0021] Further, it further includes multiple dual-port random access memories, one dual-port random access memory corresponding to one auxiliary calculation module, and the main calculation module realizes bidirectional data transmission with the corresponding auxiliary calculation module through one dual-port random access memory.

[0022] Furthermore, it also includes a data line, and the dual-port random access memory realizes data transmission with the main computing module and the corresponding auxiliary computing module through the data line.

[0023] In the above technical solution of the present invention, the harmonic compensation angle covering the delay in the receiving and sending processes is calculated by the main calculation module, and the harmonic modulation wave instruction is obtained by the auxiliary calculation module through compensation operation on the load harmonic current data according to the harmonic compensation angle, and the main calculation module generates a total harmonic compensation instruction based on multiple harmonic modulation wave instructions.

[0024] In summary, the harmonic angle compensation method based on multiple calculation modules of the present invention realizes the in-phase compensation of harmonics through the delay compensation technology, simplifies the steps and improves the compensation rate of each harmonic. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Shown is a multi-digital signal processor collaborative application framework diagram.

[0026] Figure 2 Shown is a flow chart of a harmonic angle compensation method based on multiple calculation modules of the present invention.

[0027] Description of the accompanying drawings:

[0028] 1-main computing module; 21, 22...2n-dual-port random access memory; 31, 32...3n-auxiliary computing module. DETAILED DESCRIPTION

[0029] The following is an explanation of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0030] It should be noted that the drawings in this specification are only used to match the contents disclosed in the specification so as to facilitate the understanding and reading of those skilled in the art, and are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance.

[0031] like Figure 1As shown in the figure, it is the first technical application scenario of multi - digital signal processor cooperation, including a main computing module 1, n dual - port random access memories (dual - port random access memory 21 to dual - port random access memory 2n) and n auxiliary computing modules (auxiliary computing module 31 to auxiliary computing module 3n). One of the dual - port random access memories corresponds to one of the auxiliary computing modules (dual - port random access memory 21 corresponds to auxiliary computing module 31, dual - port random access memory 22 corresponds to auxiliary computing module 32, and so on until dual - port random access memory 2n corresponds to auxiliary computing module 3n). The main computing module 1 realizes bidirectional data transmission with the corresponding auxiliary computing module through one of the dual - port random access memories. The dual - port random access memory realizes data transmission with the main computing module 1 and the corresponding auxiliary computing module through data lines. When a larger algorithm operation amount is required, the number of the auxiliary computing modules and the number of the corresponding dual - port random access memories are proportional to the operation performance.

[0032] The main computing module 1 samples the load current data and transmits the sampled data to the auxiliary computing module 31 through the dual - port random access memory 21. After receiving the sampled data, the auxiliary computing module 31 takes corresponding harmonic compensation commands on it to obtain delay compensation data. The auxiliary computing module 31 writes the delay compensation data back to the main computing module 1 through the dual - port random access memory 21. Similarly, after n identical steps, the main computing module 1 generates a total harmonic compensation instruction after receiving n pieces of delay compensation data transmitted by n auxiliary computing modules. The bidirectional data transmission between the main computing module 1 and n auxiliary computing modules realizes the in - phase compensation of harmonics. During the working process of the main computing module 1, it realizes the control of writing and reading to prevent data conflict situations; the auxiliary computing module is used to generate the harmonic compensation command, and the harmonic compensation command carries a compensation angle, and the compensation angle covers the delay during the receiving and sending processes.

[0033] In this application scenario, the main computing module 1 is a main control digital signal processor, and n auxiliary computing modules are auxiliary algorithm digital signal processors. The present invention is also applicable to the cooperation scenario of multi - core digital signal processors, and both the main computing module 1 and the auxiliary computing modules are core control digital signal processors.

[0034] As Figure 2 shown, a harmonic angle compensation method based on multiple computing modules of the present invention includes:

[0035] Step S1, the main computing module samples the load current to obtain a sampled value, and after performing a fast Fourier transform (FFT) on the sampled value, calculates the load harmonic current data and the harmonic compensation angle θ. The calculation formula of the harmonic compensation angle θ is as follows:

[0036] θ = kharm * C,

[0037] where kharm is the harmonic order, and C is the compensation angle constant corresponding to the identified harmonic order. This constant is obtained from the analysis of a large number of experimental application data.

[0038] Step S2: The auxiliary calculation module receives the load harmonic current data obtained by the main calculation module and decomposes the load harmonic current data into a complex form with the original real part real and the original imaginary part imag.

[0039] Step S3: The auxiliary calculation module receives the harmonic compensation angle θ obtained by the main calculation module and calculates the compensation factor k according to the harmonic compensation angle θ 1 and the compensation factor k 2 , and the relevant calculation formula is as follows:

[0040]

[0041]

[0042] Step S4: The auxiliary calculation module performs a compensation operation on the original real part real and the original imaginary part imag according to the compensation factor k 1 and the compensation factor k 2 to obtain the compensated real part real * and the compensated imaginary part imag * , and the relevant calculation formula is as follows:

[0043] real * = real * k 1 + imag * k 2 ,

[0044] imag * = imag * k 1 + real * k 2 .

[0045] Step S5: The auxiliary calculation module generates a harmonic modulation wave according to the compensated real part real * and the compensated imaginary part imag * . The method of generating the harmonic modulation wave can be proportional resonance or multiple control, etc.

[0046] Step S6: The auxiliary calculation module writes the generated harmonic modulation wave instruction back to the main calculation module, and the main calculation module generates a total harmonic compensation instruction according to the multiple harmonic modulation wave instructions transmitted by multiple auxiliary calculation modules.

[0047] The present invention adopts an adaptive means. After identifying the load harmonics, it calculates in real time the required harmonic compensation angle to achieve the best harmonic compensation effect. The multi-digital signal processor cooperation technology, in cooperation with the dual-port random access memory, refreshes the data in a timely manner, updates the information transmitted by each digital signal processor through the data line in a timely manner, and the delay is determined, which is convenient for on-site implementation.

[0048] It can be understood that the above specific description of the present invention is only for explaining the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced to achieve the same technical effect; as long as it meets the use requirements, it is within the protection scope of the present invention.

Claims

1. A harmonic angle compensation method based on multiple calculation modules, including a main calculation module and multiple auxiliary calculation modules. The main calculation module samples the load current and then generates a harmonic compensation angle to transmit to the auxiliary calculation modules. The auxiliary calculation modules perform compensation calculations on the load current and then transmit the obtained harmonic modulation wave instructions to the main calculation module. The main calculation module generates a total harmonic compensation instruction according to multiple harmonic modulation wave instructions. Characterized in that: Including: Step S1, the main calculation module samples the load current to obtain a sampling value, and performs Fourier transform on the sampling value and then calculates to obtain load harmonic current data and a harmonic compensation angle. Step S2, the auxiliary calculation module receives the load harmonic current data obtained by the main calculation module, and decomposes the load harmonic current data into a complex form with a real part and an imaginary part. Step S3, the auxiliary calculation module receives the harmonic compensation angle calculated by the main calculation module, and performs a compensation operation on the complex-form load harmonic current data according to the harmonic compensation angle. Step S4, the auxiliary calculation module generates a harmonic modulation wave instruction according to the load harmonic current data that has undergone the compensation operation. Step S5, the auxiliary calculation module writes the generated harmonic modulation wave instruction back to the main calculation module, and the main calculation module generates a total harmonic compensation instruction according to multiple harmonic modulation wave instructions transmitted by multiple auxiliary calculation modules.

2. A harmonic angle compensation method based on multiple calculation modules according to claim 1, Characterized in that: Step S3 further includes step S31, the auxiliary calculation module receives the harmonic compensation angle calculated by the main calculation module, and calculates a compensation factor according to the harmonic compensation angle.

3. A harmonic angle compensation method based on multiple calculation modules according to claim 2, Characterized in that: The compensation factor k is calculated based on the harmonic compensation angle θ 1 and the compensation factor k 2 The formula is as follows:

4. A harmonic angle compensation method based on multiple calculation modules according to claim 3, Characterized in that: Step S3 further includes step S32, the auxiliary calculation module performs a compensation operation on the complex-form load harmonic current data according to the compensation factor to obtain a compensated real part and a compensated imaginary part.

5. A harmonic angle compensation method based on multiple calculation modules according to claim 4, Characterized in that: The relevant calculation formulas for the compensation operation are as follows: real * = real * k 1 + imag * k 2 , imag * = imag * k 1 + real * k 2 。 where real * is the real part after compensation, imag * is the imaginary part after compensation, real is the real part of the load harmonic current data before the compensation operation, and imag is the imaginary part of the load harmonic current data before the compensation operation.

6. A harmonic angle compensation method based on multiple calculation modules according to claim 1, Characterized in that: It further includes multiple dual-port random access memories. One dual-port random access memory corresponds to one auxiliary calculation module, and the main calculation module realizes bidirectional data transmission with the corresponding auxiliary calculation module through one dual-port random access memory.

7. A harmonic angle compensation method based on multiple calculation modules according to claim 6, Characterized in that: It further includes a data line, and the dual-port random access memory realizes data transmission with the main calculation module and the corresponding auxiliary calculation module through the data line.

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