Rapid calculation method for effective value in power supply

Abstract

The invention discloses a method for quickly calculating an effective value in power supply, which comprises the following steps of: digitally sampling an input alternating current signal, segmenting the signal according to a time axis, generally, the length of each segment is a plurality of sampling periods, each segment of signal comprises a plurality of sampling points, and the signal is ensured to be more stable in each segment; the square of the instantaneous value of each section of signal is calculated, after the sum of the instantaneous values obtained after segmented weighted averaging is obtained, the square root of the sum is taken, and the effective value of the signal section is obtained; the final effective value is a comprehensive average value of the effective values of all the sections, or the effective value result of a certain section of signal is directly output according to a specific application scene. In the calculation process, a numerical iterative calculation mode is adopted. The efficiency of the rapid effective value calculation method is improved by more than ten times, and the method is mainly applied to effective value calculation of power input signals in the power electronic industry.

Description

Technical Field

[0001] The invention relates to a power supply system, and in particular to a method for quickly calculating an effective value in power supply. Background Art

[0002] At present, in power supply systems, the root mean square (RMS) of AC signals is an important parameter that characterizes the average energy of voltage or current. The calculation of RMS is widely used in power supply design, load matching, and power evaluation. Traditional RMS calculation usually uses the integration method, which is complex and takes a long time to calculate. Therefore, for real-time signal processing, how to improve the speed of RMS calculation has become an important technical issue in power systems and power equipment.

[0003] Existing technology and defects:

[0004] At present, effective value calculation mainly includes methods based on numerical integration, Fourier transform or square average. However, these methods have large computational complexity and poor real-time performance, which is not conducive to use in power systems that require fast response. Therefore, a new method that can quickly and accurately calculate the effective value of AC signals is urgently needed.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a method for quickly calculating the effective value in power supply to solve the above technical problems existing in the prior art.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] The method for quickly calculating the effective value in power supply of the present invention comprises the steps of:

[0009] Input signal sampling and segmentation: digitally sample the input AC signal and segment the signal according to the time axis. Usually, each segment is several sampling cycles long and each segment contains several sampling points to ensure that the signal is relatively stable in each segment.

[0010] Instantaneous value calculation: Calculate the square of the instantaneous value of each signal segment. The formula is as follows:

[0011]

[0012] Among them, U sample is the instantaneous voltage value of the i-th sampling point;

[0013] Square root calculation: After obtaining the sum of the instantaneous values ​​after the segment weighted average, take its square root to obtain the effective value of the signal segment:

[0014]

[0015] Where N is the total number of sampling points;

[0016] Overall effective value output: The final effective value is the comprehensive average of the effective values ​​of each segment, or according to the specific application scenario, the effective value result of a certain signal segment is directly output.

[0017] Compared with the prior art, the fast effective value calculation method in power supply provided by the present invention is more than ten times more efficient than the conventional effective value calculation method. The invention is mainly used for the effective value calculation of power supply input signal in the power electronics industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a method for quickly calculating effective values ​​in power supply provided by an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the time consumption measured by the conventional effective value calculation method.

[0020] Figure 3 The figure is a schematic diagram of the time consumption measured by the fast effective value calculation method according to the embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, which does not constitute a limitation of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0022] First, the terms that may be used in this article are explained as follows:

[0023] The term “and / or” means that either or both of them can be realized at the same time. For example, X and / or Y means both “X” or “Y” and “X and Y”.

[0024] The terms "include", "comprises", "contains", "has" or other descriptions with similar semantics should be interpreted as non-exclusive inclusion. For example, including certain technical feature elements (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or products, etc.) should be interpreted as including not only certain technical feature elements explicitly listed, but also other technical feature elements known in the art that are not explicitly listed.

[0025] The term "consisting of..." means excluding any technical feature elements not explicitly listed. If this term is used in a claim, it will make the claim closed, so that it does not contain technical feature elements other than the technical feature elements explicitly listed, except for the conventional impurities related to them. If this term only appears in a clause of a claim, it only limits the elements explicitly listed in the clause, and the elements recorded in other clauses are not excluded from the overall claim.

[0026] Unless otherwise specified or limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this article can be understood according to specific circumstances.

[0027] The orientation or position relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the drawings and are only for the convenience and simplification of description, and do not explicitly or implicitly indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation of this document.

[0028] The contents not described in detail in the examples of the present invention belong to the prior art known to professionals in the field. If no specific conditions are specified in the examples of the present invention, the conditions are carried out according to the conventional conditions in the field or the conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used in the examples of the present invention, they are all conventional products that can be purchased commercially.

[0029] The method for quickly calculating the effective value in power supply of the present invention comprises the steps of:

[0030] Input signal sampling and segmentation: digitally sample the input AC signal and segment the signal according to the time axis. Usually, each segment is several sampling cycles long and each segment contains several sampling points to ensure that the signal is relatively stable in each segment.

[0031] Instantaneous value calculation: Calculate the square of the instantaneous value of each signal segment. The formula is as follows:

[0032]

[0033] Among them, U sample is the instantaneous voltage value of the i-th sampling point;

[0034] Square root calculation: After obtaining the sum of the instantaneous values ​​after the segment weighted average, take its square root to obtain the effective value of the signal segment:

[0035]

[0036] Where N is the total number of sampling points;

[0037] Overall effective value output: The final effective value is the comprehensive average of the effective values ​​of each segment, or according to the specific application scenario, the effective value result of a certain signal segment is directly output.

[0038] In the above calculation process, a numerical iterative calculation method is adopted, that is, in each calculation cycle, the above process is not completely repeated, but only the square of the data of the current cycle is calculated, and the square root of the square value of the initial cycle is subtracted during the calculation process of the current cycle, and then the square root of the square value of the current cycle is added.

[0039] In summary, the fast effective value calculation method in the power supply of the embodiment of the present invention is more than ten times more efficient than the conventional effective value calculation method. The invention is mainly used for the effective value calculation of the power supply input signal in the power electronics industry.

[0040] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the embodiments of the present invention are described in detail with specific embodiments below.

[0041] Example 1

[0042] Description of the invention principle

[0043] To achieve the above object, the present invention adopts the following technical solutions:

[0044] Input signal sampling and segmentation: Digitally sample the input AC signal and segment the signal along the time axis. Usually, each segment is several sampling cycles long. Each segment contains several sampling points to ensure that the signal is relatively stable within each segment.

[0045] Instantaneous value calculation: Calculate the square of the instantaneous value of each signal segment. The formula is as follows:

[0046]

[0047] Among them, U sample is the instantaneous voltage value of the i-th sampling point.

[0048] Square root calculation: After obtaining the sum of the instantaneous values ​​after the segment weighted average, take its square root to obtain the effective value of the signal segment:

[0049]

[0050] Where N is the total number of sampling points.

[0051] Overall effective value output: The final effective value is the comprehensive average of the effective values ​​of each segment, or according to the specific application scenario, the effective value result of a certain signal segment is directly output.

[0052] Cyclic calculation iteration: When using the square average method to calculate the effective value, the largest amount of calculation is the square root and square root of N cycles. Therefore, the present invention adopts a numerical iteration calculation method, that is, in each calculation cycle, the above process is not completely repeated, but only the square of the data of the current cycle is calculated. In the calculation process of the current cycle, the square root of the square value of the initial cycle is subtracted, and then the square root of the square value of the current cycle is added. The schematic diagram is shown as follows: Figure 1 As shown. In this way, the time calculation complexity is only 1 / N times of the existing N-cycle calculation method, and the calculation time will be greatly shortened.

[0053] Testing and experimental verification

[0054] The fast effective value calculation method proposed in the present invention is compared with the conventional effective value calculation method. The input signal is 50 Hz and the number of sampling points is 200. The time consumption measured by the conventional effective value calculation method is as follows: Figure 2 As shown in Figure 1, the single cycle calculation takes about 518us. The time consumed by the fast effective value calculation method is as follows: Figure 3 As shown, the single cycle calculation takes about 7.46us. Compared with the conventional effective value calculation method, the fast effective value calculation method of the present invention is more efficient than dozens of times.

[0055] The invention is mainly used for calculating the effective value of power input signals in the power electronics industry.

[0056] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims. The information disclosed in the background technology section of this article is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as an admission or in any form that the information constitutes prior art known to those skilled in the art.

Claims

1. A method for quickly calculating the effective value of power supply, characterized in that: Includes steps: Input signal sampling and segmentation: digitally sample the input AC signal and segment the signal according to the time axis. Usually, each segment is several sampling cycles long and each segment contains several sampling points to ensure that the signal is relatively stable in each segment. Instantaneous value calculation: Calculate the square of the instantaneous value of each signal segment. The formula is as follows: Among them, Usample is the instantaneous voltage value of the i-th sampling point; Square root calculation: After obtaining the sum of the instantaneous values ​​after the segment weighted average, take its square root to obtain the effective value of the signal segment: Where N is the total number of sampling points; Overall effective value output: The final effective value is the comprehensive average of the effective values ​​of each segment, or according to the specific application scenario, the effective value result of a certain signal segment is directly output.

2. The method for quickly calculating the effective value in power supply according to claim 1, characterized in that: In the above calculation process, a numerical iterative calculation method is adopted, that is, in each calculation cycle, the above process is not completely repeated, but only the square of the data of the current cycle is calculated, and the square root of the square value of the initial cycle is subtracted during the calculation process of the current cycle, and then the square root of the square value of the current cycle is added.

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