A method for evaluating the precision of relay protection considering the errors of ADC chip and filtering algorithm

Abstract

This invention discloses a method for evaluating the accuracy of relay protection considering the errors of ADC chips and filtering algorithms, comprising: calculating the actual single-point sampled value of the relay protection device; calculating the actual calculated value of the relay protection device based on the actual single-point sampled value; calculating the theoretical calculated value of the relay protection device based on the theoretical sampled value; calculating the ADC sampling error and filtering algorithm error of the relay protection device based on the original signal value, actual calculated value, and theoretical calculated value; and evaluating whether the errors generated by the ADC chip and filtering algorithm in the relay protection algorithm meet the standard requirements based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements.

Description

Technical Field

[0001] This invention relates to the field of power system relay protection, and more specifically, to a method and apparatus for evaluating the accuracy of relay protection that takes into account the errors of ADC chips and filtering algorithms. Background Technology

[0002] Relay protection devices primarily determine the current operating status of a power system based on changes in protected electrical quantities (current, voltage, power, impedance, and frequency, etc.). When a fault occurs in the system, the voltage and current flowing through the faulty equipment will change. To promptly clear the fault, the protection device should be able to accurately and timely acquire these changes in fault characteristic quantities. The analog-to-digital converter (ADC) chip and sampling circuit, as key components of the relay protection data acquisition system, collect data that is a crucial data source for the protection device. Their performance directly determines the correctness of the commands issued by the relay protection device, as well as the accuracy and speed of the protection action. In particular, accuracy indicators such as resolution and noise ratio directly affect the parameters or fault characteristic quantities required for protection criteria. Abnormal sampling information caused by accuracy errors will lead to erroneous operation of the relay protection device, causing serious damage to the power system.

[0003] Due to accuracy issues with ADC chips, relay protection devices may fail to meet standard requirements for sampling accuracy under certain operating conditions, leading to maloperation or failure to operate. However, there is currently no research plan addressing the impact of ADC chip and filtering algorithm errors on the sampling and processing data in relay protection devices, resulting in low accuracy and poor reliability of relay protection actions. Summary of the Invention

[0004] To address the technical problems of low accuracy and poor reliability of relay protection operations in existing technologies, this invention provides a method and apparatus for evaluating the accuracy of relay protection that takes into account the errors of ADC chips and filtering algorithms.

[0005] According to one aspect of the present invention, a method for evaluating the accuracy of relay protection considering errors of ADC chips and filtering algorithms is provided, comprising:

[0006] Calculate the actual single-point sampled value of the relay protection device;

[0007] Calculate the actual calculated value of the relay protection device based on the actual single-point sampling value of the relay protection device;

[0008] Calculate the theoretical values ​​of the relay protection device based on the sampled theoretical values.

[0009] Based on the original signal value, actual calculated value, and theoretical calculated value of the relay protection device, calculate the ADC sampling error and filtering algorithm error of the relay protection device;

[0010] Based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements, evaluate whether the errors generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meet the standard requirements.

[0011] Optionally, the actual single-point sampled value of the relay protection device is calculated, including:

[0012] Calculate the effective number of bits of the ADC chip;

[0013] Based on the effective number of bits of the ADC chip and considering the error caused by the current transformer in the relay protection device, calculate the actual single-point sampling value of the relay protection device.

[0014] Alternatively, the effective number of bits N of the ADC chip can be calculated using the following formula:

[0015]

[0016] In the formula, N is the effective number of bits of the ADC chip, and SNR is the maximum signal-to-noise ratio of the ADC chip.

[0017] Optionally, based on the effective number of bits of the ADC chip and considering the error caused by the current transformer within the relay protection device, the actual single-point sampled value of the relay protection device is calculated, including:

[0018] Based on the effective number of bits of the ADC chip, the maximum error of the protected single-point sample value of the ADC chip is calculated using the following formula:

[0019]

[0020] In the formula, ε noise The maximum error of a single-point sampled value protected by the ADC chip; N is the effective number of bits of the ADC chip; ±I MAX These are the upper and lower limits for the sampled values;

[0021] Considering the error caused by the current transformer in the relay protection device, the output value of the ADC chip is calculated using the following formula:

[0022] i=K trans (I(n)+ε T )+ε noise ;

[0023] In the formula, i is the output value of the ADC chip; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical value of the instantaneous sampled value; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise To protect the ADC chip from the maximum error of a single-point sampled value;

[0024] Based on the output value of the ADC chip, the actual single-point sampled value of the relay protection device is calculated using the following formula:

[0025]

[0026] In the formula, I ADC (n) represents the actual single-point sampling value of the relay protection device; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical sampling value of the relay protection device; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise This is to protect the ADC chip from the maximum error of a single-point sampled value.

[0027] Optionally, the actual calculated value of the relay protection device is calculated based on the actual single-point sampled value of the relay protection device, including:

[0028] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the actual single-point sampled value of the relay protection device:

[0029] i ADC =F[I ADC (n)];

[0030] In the formula, i ADC This refers to the actual calculated value of the relay protection device; I ADC (n) represents the actual single-point sampled value of the relay protection device; F[X] represents the Fourier transform algorithm used.

[0031] Optionally, based on the sampled theoretical values ​​of the relay protection device, the theoretical calculated values ​​of the relay protection device are calculated, including:

[0032] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the sampled theoretical value of the relay protection device:

[0033] i F =F[I(n)];

[0034] In the formula, i F denoted as , where is the theoretical value of the sampling of the relay protection device; I(n) is the theoretical value of the sampling of the relay protection device; F[X] is the Fourier transform algorithm used.

[0035] Optionally, based on the original signal value, actual calculated value, and theoretical calculated value of the relay protection device, the ADC sampling error and filtering algorithm error of the relay protection device are calculated, including:

[0036] Based on the actual and theoretical calculated values ​​of the relay protection device, the ADC sampling error of the relay protection device is calculated using the following formula:

[0037] ε ADC =i ADC -i F ;

[0038] In the formula, ε ADC For the ADC sampling error of the relay protection device; i ADC The actual calculated value for the relay protection device; i F These are the theoretical values ​​sampled by the relay protection device;

[0039] Based on the original signal value and theoretical calculation value of the relay protection device, the filtering algorithm error of the relay protection device is calculated using the following formula:

[0040] ε F =i F -i(t);

[0041] In the formula, ε F For the filtering algorithm error of the relay protection device; i F t is the theoretical value of the sampling of the relay protection device; i(t) is the original signal value of the relay protection device.

[0042] Optionally, based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements, evaluate whether the error generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meets the standard requirements, including:

[0043] When the sampled value is AC current, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0044] MAX(ε F +ε ADC )≤±0.02I n or

[0045] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC I represents the ADC sampling error of the relay protection device; i(t) represents the original signal value of the relay protection device; I n The rated value of the sampling current for the relay protection device;

[0046] When the sampled value is AC voltage, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0047] MAX(ε F +ε ADC )≤±0.02U n or

[0048] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC U is the ADC sampling error of the relay protection device; u(t) is the original voltage value of the relay protection device; U n This refers to the rated value of the sampling voltage for the relay protection device.

[0049] According to another aspect of the present invention, a relay protection accuracy evaluation device considering the errors of ADC chips and filtering algorithms is provided, comprising:

[0050] The first calculation module is used to calculate the actual single-point sampled value of the relay protection device;

[0051] The second calculation module is used to calculate the actual calculated value of the relay protection device based on the actual single-point sampling value of the relay protection device.

[0052] The third calculation module is used to calculate the theoretical value of the relay protection device based on the sampled theoretical value of the relay protection device;

[0053] The fourth calculation module is used to calculate the ADC sampling error and filtering algorithm error of the relay protection device based on the original signal value, actual calculated value and theoretical calculated value of the relay protection device;

[0054] The accuracy evaluation module is used to evaluate whether the errors generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meet the standard requirements, based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements.

[0055] Optionally, the first computing module is specifically used for:

[0056] Calculate the effective number of bits of the ADC chip;

[0057] Based on the effective number of bits of the ADC chip and considering the error caused by the current transformer in the relay protection device, calculate the actual single-point sampling value of the relay protection device.

[0058] Optionally, the first calculation module is also specifically used to calculate the effective number of bits N of the ADC chip using the following formula:

[0059]

[0060] In the formula, N is the effective number of bits of the ADC chip, and SNR is the maximum signal-to-noise ratio of the ADC chip.

[0061] Optionally, the first calculation module is also specifically used for:

[0062] Based on the effective number of bits of the ADC chip, the maximum error of the protected single-point sample value of the ADC chip is calculated using the following formula:

[0063]

[0064] In the formula, ε noise The maximum error of a single-point sampled value protected by the ADC chip; N is the effective number of bits of the ADC chip; ±I MAX These are the upper and lower limits for the sampled values;

[0065] Considering the error caused by the current transformer in the relay protection device, the output value of the ADC chip is calculated using the following formula:

[0066] i=K trans (I(n)+ε T )+ε noise ;

[0067] In the formula, i is the output value of the ADC chip; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical value of the instantaneous sampled value; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise To protect the ADC chip from the maximum error of a single-point sampled value;

[0068] Based on the output value of the ADC chip, the actual single-point sampled value of the relay protection device is calculated using the following formula:

[0069]

[0070] In the formula, I ADC (n) represents the actual single-point sampling value of the relay protection device; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical sampling value of the relay protection device; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise This is to protect the ADC chip from the maximum error of a single-point sampled value.

[0071] Optionally, the second calculation module is specifically used for:

[0072] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the actual single-point sampled value of the relay protection device:

[0073] i ADC =F[I ADC (n)];

[0074] In the formula, i ADC This refers to the actual calculated value of the relay protection device; I ADC (n) represents the actual single-point sampled value of the relay protection device; F[X] represents the Fourier transform algorithm used.

[0075] Optionally, the third calculation module is specifically used for:

[0076] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the sampled theoretical value of the relay protection device:

[0077] i F =F[I(n)];

[0078] In the formula, i F denoted as , where is the theoretical value of the sampling of the relay protection device; I(n) is the theoretical value of the sampling of the relay protection device; F[X] is the Fourier transform algorithm used.

[0079] Optionally, the fourth calculation module is specifically used for:

[0080] Based on the actual and theoretical calculated values ​​of the relay protection device, the ADC sampling error of the relay protection device is calculated using the following formula:

[0081] ε ADC =i ADC -i F ;

[0082] In the formula, ε ADC For the ADC sampling error of the relay protection device; i ADC The actual calculated value for the relay protection device; i F These are the theoretical values ​​sampled by the relay protection device;

[0083] Based on the original signal value and theoretical calculation value of the relay protection device, the filtering algorithm error of the relay protection device is calculated using the following formula:

[0084] ε F =i F -i(t);

[0085] In the formula, ε F For the filtering algorithm error of the relay protection device; i F t is the theoretical value of the sampling of the relay protection device; i(t) is the original signal value of the relay protection device.

[0086] Optionally, the accuracy evaluation module is specifically used for:

[0087] When the sampled value is AC current, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0088] MAX(ε F +ε ADC )≤±0.02I n or

[0089] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC I represents the ADC sampling error of the relay protection device; i(t) represents the original signal value of the relay protection device; I n The rated value of the sampling current for the relay protection device;

[0090] When the sampled value is AC voltage, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0091] MAX(ε F +ε ADC )≤±0.02U n or

[0092] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC U is the ADC sampling error of the relay protection device; u(t) is the original voltage value of the relay protection device; U n This refers to the rated value of the sampling voltage for the relay protection device.

[0093] According to another aspect of the present invention, a computer-readable storage medium is provided, the storage medium storing a computer program for performing the methods described in any of the above aspects of the present invention.

[0094] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: a processor; a memory for storing executable instructions of the processor; the processor being configured to read the executable instructions from the memory and execute the instructions to implement the method described in any of the preceding aspects of the present invention.

[0095] Therefore, this invention first calculates the actual single-point sampled value of the relay protection device. Then, based on the actual single-point sampled value, it calculates the actual calculated value of the relay protection device. Next, based on the theoretical sampled value of the relay protection device, it calculates the theoretical calculated value of the relay protection device. Then, based on the original signal value, actual calculated value, and theoretical calculated value of the relay protection device, it calculates the ADC sampling error and filtering algorithm error of the relay protection device. Finally, based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements, it evaluates whether the errors generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meet the standard requirements. This invention aims to overcome the behavior of relay protection devices failing to meet the standard requirements in some special operating conditions due to ADC chip accuracy issues, resulting in maloperation or failure to operate. It proposes a relay protection accuracy evaluation method that considers the errors of the ADC chip and filtering algorithm on the sampled data processed in the relay protection device, with the purpose of assessing whether the errors generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meet the standard requirements. This invention, through derivation and analysis of the data conversion process of ADC chips, derives the relationship between the ADC sampling error of a relay protection device and the actual and theoretical calculated values ​​of the ADC chip, thereby calculating the ADC sampling error of the relay protection device. Through derivation and analysis of the filtering algorithm, the error relationship generated by the filtering algorithm is derived, thereby calculating the filtering algorithm error of the relay protection device. Finally, based on the ADC sampling error and the filtering algorithm error, and combined with the accuracy error requirements of the relay protection device technical specifications, the error margin is calculated to evaluate whether the error generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meets the standard requirements, ensuring the accuracy and reliability of the relay protection action. It also provides a theoretical basis for chip selection, device development, and optimization iteration of relay protection devices. Attached Figure Description

[0096] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0097] Figure 1This is a flowchart illustrating an exemplary embodiment of the present invention for evaluating the accuracy of relay protection considering the errors of ADC chips and filtering algorithms.

[0098] Figure 2 This is a diagram illustrating the main error composition and sources of a relay protection device provided in an exemplary embodiment of the present invention;

[0099] Figure 3 This is an overall flowchart of a relay protection accuracy evaluation method considering the errors of ADC chips and filtering algorithms provided in an exemplary embodiment of the present invention.

[0100] Figure 4 This is a schematic diagram of the structure of a relay protection accuracy evaluation device that takes into account the errors of ADC chip and filtering algorithm provided in an exemplary embodiment of the present invention;

[0101] Figure 5 This is the structure of an electronic device provided in an exemplary embodiment of the present invention. Detailed Implementation

[0102] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein.

[0103] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0104] Those skilled in the art will understand that the terms "first," "second," etc., in the embodiments of the present invention are only used to distinguish different steps, devices, or modules, and do not represent any specific technical meaning, nor do they indicate a necessary logical order between them.

[0105] It should also be understood that in the embodiments of the present invention, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0106] It should also be understood that any component, data or structure mentioned in the embodiments of the present invention can generally be understood as one or more unless explicitly defined or given contrary instructions in the context.

[0107] Furthermore, the term "and / or" in this invention is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this invention generally indicates that the preceding and following related objects have an "or" relationship.

[0108] It should also be understood that the description of the various embodiments in this invention emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0109] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0110] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0111] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0112] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0113] The embodiments of this invention can be applied to electronic devices such as terminal devices, computer systems, and servers, and can operate together with a wide range of other general-purpose or special-purpose computing system environments or configurations. Well-known examples of terminal devices, computing systems, environments, and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, and servers include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputer systems, mainframe computer systems, and distributed cloud computing environments including any of the above systems, etc.

[0114] Electronic devices such as terminal devices, computer systems, and servers can be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. Typically, program modules can include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers can be implemented in distributed cloud computing environments, where tasks are executed by remote processing devices linked through communication networks. In distributed cloud computing environments, program modules can reside on local or remote computing system storage media, including storage devices.

[0115] Exemplary methods

[0116] Figure 1This is a flowchart illustrating a relay protection accuracy evaluation method considering ADC chip and filtering algorithm errors, provided by an exemplary embodiment of the present invention. This embodiment can be applied to electronic devices, such as... Figure 1 As shown, the relay protection accuracy evaluation method 100, which takes into account the errors of the ADC chip and filtering algorithm, includes the following steps:

[0117] Step 101: Calculate the actual single-point sampling value of the relay protection device.

[0118] In an embodiment of the present invention, see Figure 2 As shown, before calculating the actual single-point sampled value of the relay protection device, it is necessary to identify the main sources of error in the relay protection calculation. These main sources include errors caused by the accuracy of the ADC chip and sampling circuit, and errors caused during the filtering algorithm process. The accuracy error of the ADC chip and sampling circuit mainly consists of two parts: the error generated by the ADC chip during the analog-to-digital conversion of data, and the error generated by components such as the current transformer within the device.

[0119] Optionally, calculating the actual single-point sampled value of the relay protection device includes: calculating the effective number of bits of the ADC chip; and, based on the effective number of bits of the ADC chip and considering the error caused by the current transformer within the relay protection device, calculating the actual single-point sampled value of the relay protection device.

[0120] Alternatively, the effective number of bits N of the ADC chip can be calculated using the following formula:

[0121]

[0122] In the formula, N is the effective number of bits of the ADC chip, and SNR is the maximum signal-to-noise ratio of the ADC chip.

[0123] In this embodiment of the invention, the error generated by the ADC chip during the analog-to-digital conversion of data is mainly determined by the quantization noise, which is caused by the overlap of the frequency bands of the signal and noise. The maximum signal-to-noise ratio (SNR) of an analog-to-digital converter with a given number of bits (N) is defined by the quantization noise.

[0124] For a sinusoidal input signal, the theoretical signal-to-noise ratio (SNR) follows the 6dB rule, and the calculation formula is as follows:

[0125] SNR Nyquist (dB) = 6.02N + 1.76;

[0126] In the formula, N is the number of bits in the analog-to-digital converter (ADC chip). That is, for every 1 bit increase in the number of bits in the ADC, the SNR value increases by about 6dB.

[0127] Therefore, the actual effective number of bits of the ADC chip is:

[0128]

[0129] Optionally, based on the effective number of bits of the ADC chip and considering the error caused by the current transformer within the relay protection device, the actual single-point sampled value of the relay protection device is calculated, including:

[0130] Based on the effective number of bits of the ADC chip, the maximum error of the protected single-point sample value of the ADC chip is calculated using the following formula:

[0131]

[0132] In the formula, ε noise The maximum error of a single-point sampled value protected by the ADC chip; N is the effective number of bits of the ADC chip; ±I MAX These are the upper and lower limits for the sampled values;

[0133] Considering the error caused by the current transformer in the relay protection device, the output value of the ADC chip is calculated using the following formula:

[0134] i=K trans (I(n)+ε T )+ε noise ;

[0135] In the formula, i is the output value of the ADC chip; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical value of the instantaneous sampled value; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise To protect the ADC chip from the maximum error of a single-point sampled value;

[0136] Based on the output value of the ADC chip, the actual single-point sampled value of the relay protection device is calculated using the following formula:

[0137]

[0138] In the formula, I ADC (n) represents the actual single-point sampling value of the relay protection device; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical sampling value of the relay protection device; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise This is to protect the ADC chip from the maximum error of a single-point sampled value.

[0139] In this embodiment of the invention, in the relay protection algorithm, the ADC chip converts continuously changing analog signals into discrete digital signals. For protection, it takes continuous quadratic input signals, passes them through sampling points, and then performs Fourier transform to obtain the required electrical quantities.

[0140] At this point, the maximum error of the protected single-point sample value is:

[0141]

[0142] Analysis of the error impact of components such as current transformers in relay protection devices. Assume the secondary input signal is i(t), the theoretical instantaneous sampled value is I(n), and the combined transformation ratio of the current transformers and analog amplifier circuits within the device is K. trans The overall error generated in this step is ε. T The instantaneous value input to the ADC chip is K. trans (I(n)+ε T The small signal of the ADC output value is:

[0143] i=K trans (I(n)+ε T )+ε noise ;

[0144] The actual single-point sampling value of the relay protection device is obtained as follows:

[0145]

[0146] Step 102: Calculate the actual calculated value of the relay protection device based on the actual single-point sampling value of the relay protection device.

[0147] Optionally, the actual calculated value of the relay protection device is calculated based on the actual single-point sampled value of the relay protection device, including:

[0148] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the actual single-point sampled value of the relay protection device:

[0149] i ADC =F[I ADC (n)];

[0150] In the formula, i ADC This refers to the actual calculated value of the relay protection device; I ADC (n) represents the actual single-point sampled value of the relay protection device; F[X] represents the Fourier transform algorithm used.

[0151] In this embodiment of the invention, the Fourier transform used is F[X]. Depending on the type of relay protection device, either the full-wave Fourier algorithm or the half-wave Fourier algorithm is used to calculate the actual calculated value i of the relay protection device. ADC =F[I ADC (n)].

[0152] Step 103: Calculate the theoretical value of the relay protection device based on the sampled theoretical value of the relay protection device.

[0153] Optionally, based on the sampled theoretical values ​​of the relay protection device, the theoretical calculated values ​​of the relay protection device are calculated, including:

[0154] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the sampled theoretical value of the relay protection device:

[0155] i F =F[I(n)];

[0156] In the formula, i F denoted as , where is the theoretical value of the sampling of the relay protection device; I(n) is the theoretical value of the sampling of the relay protection device; F[X] is the Fourier transform algorithm used.

[0157] In this embodiment of the invention, the Fourier transform used is F[X]. Depending on the type of relay protection device, either the full-wave Fourier algorithm or the half-wave Fourier algorithm is used to calculate the theoretical value i of the relay protection device. F =F[I(n)].

[0158] Step 104: Calculate the ADC sampling error and filtering algorithm error of the relay protection device based on the original signal value, actual calculated value and theoretical calculated value of the relay protection device.

[0159] Optionally, based on the original signal value, actual calculated value, and theoretical calculated value of the relay protection device, the ADC sampling error and filtering algorithm error of the relay protection device are calculated, including:

[0160] Based on the actual and theoretical calculated values ​​of the relay protection device, the ADC sampling error of the relay protection device is calculated using the following formula:

[0161] ε ADC =i ADC -i F ;

[0162] In the formula, ε ADC For the ADC sampling error of the relay protection device; i ADC The actual calculated value for the relay protection device; i F These are the theoretical values ​​sampled by the relay protection device;

[0163] Based on the original signal value and theoretical calculation value of the relay protection device, the filtering algorithm error of the relay protection device is calculated using the following formula:

[0164] ε F =i F -i(t);

[0165] In the formula, ε F For the filtering algorithm error of the relay protection device; i F t is the theoretical value of the sampling of the relay protection device; i(t) is the original signal value of the relay protection device.

[0166] In this embodiment of the invention, taking the full-wave Fourier algorithm as an example, when a system fault occurs, the original signal value i(t) includes the fundamental wave, all harmonic components, and the DC attenuation component, which is...

[0167]

[0168] In the formula: I0 is the initial value of the DC attenuation component; τ is the attenuation time constant; k is the harmonic order; I k , ω represents the amplitude and initial phase of the kth harmonic; ω represents the angular frequency of the fundamental wave; and n represents the highest order of the harmonic component.

[0169] set up The above can then be expressed as

[0170]

[0171] By performing N synchronous samplings on a continuous signal i(t) within each period, we can obtain a discrete sampling point sequence of the signal: {i(1), i(2), ..., i(N)}, then we have:

[0172]

[0173] In the formula: T s T is the sampling interval. s =T / N, where T is one period of the fundamental frequency and n is the number of samples.

[0174] By applying the full-wave Fourier algorithm to the sampled discrete signal, the real and imaginary parts of the k-th Discrete Fourier Transform (DFT) value of the sampled signal can be obtained, and then the corresponding electrical parameters such as the amplitude and phase of the sampled signal can be obtained.

[0175] Based on the original signal value i(t) and the theoretically calculated value i after discrete transformation F The actual calculated value i of the device ADC The final error mainly includes the filtering algorithm error ε.F and ADC sampling error ε ADC They are respectively:

[0176] ε F =i F -i(t);

[0177] ε ADC =i ADC -i F .

[0178] Step 105: Based on the ADC sampling error and the filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements, evaluate whether the error generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meets the standard requirements.

[0179] Optionally, based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements, evaluate whether the error generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meets the standard requirements, including:

[0180] When the sampled value is AC current, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0181] MAX(ε F +ε ADC )≤±0.02I n or

[0182] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC I represents the ADC sampling error of the relay protection device; i(t) represents the original signal value of the relay protection device; I n The rated value of the sampling current for the relay protection device;

[0183] When the sampled value is AC voltage, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0184] MAX(ε F +ε ADC )≤±0.02U n or

[0185] In the formula, MAX(ε)F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC U is the ADC sampling error of the relay protection device; u(t) is the original voltage value of the relay protection device; U n This refers to the rated value of the sampling voltage for the relay protection device.

[0186] In this embodiment of the invention, according to the relay protection standard requirements, when the sampled value is AC current, the absolute error of the operating value is not greater than ±0.02In or the relative error is not greater than ±5%, that is...

[0187] MAX(ε F +ε ADC )≤±0.02I n or

[0188] Similarly, when the sampled value is AC voltage, the absolute error of the action value is no greater than ±0.02Un or the relative error is no greater than ±5%, that is...

[0189] MAX(ε F +ε ADC )≤±0.02U n or

[0190] Therefore, according to the above formula, the ADC sampling error (ε) ADC ) and filtering algorithm error (ε) F The sum of these factors constitutes the total error of the relay protection device, and the magnitude of the sampling error represents the accuracy of the ADC chip.

[0191] Therefore, this invention patent understands the error influence mechanism of ADC chip and filtering algorithm errors in relay protection devices, and concludes that the error mainly comes from two parts: the sampling accuracy of the ADC chip and the filtering algorithm.

[0192] This invention derives the relationship between sampling error and technical specifications of ADC chips, such as signal-to-noise ratio and effective bit depth, through derivation and analysis of the data conversion process of ADC chips. It also derives the error relationship generated by filtering algorithms through derivation and analysis, and finally calculates the error margin based on the accuracy error requirements of relay protection device technical specifications to evaluate the accuracy of the ADC chip. (See [link to relevant documentation]). Figure 3 As shown, this ensures the accuracy and reliability of relay protection operation, and also provides a theoretical basis for the selection of chips, device development and optimization iteration of relay protection devices.

[0193] Therefore, this invention first calculates the actual single-point sampled value of the relay protection device. Then, based on the actual single-point sampled value, it calculates the actual calculated value of the relay protection device. Next, based on the theoretical sampled value of the relay protection device, it calculates the theoretical calculated value of the relay protection device. Then, based on the original signal value, actual calculated value, and theoretical calculated value of the relay protection device, it calculates the ADC sampling error and filtering algorithm error of the relay protection device. Finally, based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements, it evaluates whether the errors generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meet the standard requirements. This invention aims to overcome the behavior of relay protection devices failing to meet the standard requirements in some special operating conditions due to ADC chip accuracy issues, resulting in maloperation or failure to operate. It proposes a relay protection accuracy evaluation method that considers the errors of the ADC chip and filtering algorithm on the sampled data processed in the relay protection device, with the purpose of assessing whether the errors generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meet the standard requirements. This invention, through derivation and analysis of the data conversion process of ADC chips, derives the relationship between the ADC sampling error of a relay protection device and the actual and theoretical calculated values ​​of the ADC chip, thereby calculating the ADC sampling error of the relay protection device. Through derivation and analysis of the filtering algorithm, the error relationship generated by the filtering algorithm is derived, thereby calculating the filtering algorithm error of the relay protection device. Finally, based on the ADC sampling error and the filtering algorithm error, and combined with the accuracy error requirements of the relay protection device technical specifications, the error margin is calculated to evaluate whether the error generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meets the standard requirements, ensuring the accuracy and reliability of the relay protection action. It also provides a theoretical basis for chip selection, device development, and optimization iteration of relay protection devices.

[0194] Exemplary device

[0195] Figure 4 This is a schematic diagram of the structure of a relay protection accuracy evaluation device considering the errors of the ADC chip and filtering algorithm, provided in an exemplary embodiment of the present invention. Figure 4 As shown, the device 400 includes:

[0196] The first calculation module 410 is used to calculate the actual single-point sampled value of the relay protection device;

[0197] The second calculation module 420 is used to calculate the actual calculated value of the relay protection device based on the actual single-point sampling value of the relay protection device.

[0198] The third calculation module 430 is used to calculate the theoretical calculation value of the relay protection device based on the sampled theoretical value of the relay protection device;

[0199] The fourth calculation module 440 is used to calculate the ADC sampling error and filtering algorithm error of the relay protection device based on the original signal value, actual calculated value and theoretical calculated value of the relay protection device;

[0200] The accuracy evaluation module 450 is used to evaluate whether the errors generated by the ADC chip and filtering algorithm in the relay protection algorithm meet the standard requirements, based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standard requirements.

[0201] Optionally, the first calculation module 410 is specifically used for:

[0202] Calculate the effective number of bits of the ADC chip;

[0203] Based on the effective number of bits of the ADC chip and considering the error caused by the current transformer in the relay protection device, calculate the actual single-point sampling value of the relay protection device.

[0204] Optionally, the first calculation module 410 is also specifically used to calculate the effective number of bits N of the ADC chip using the following formula:

[0205]

[0206] In the formula, N is the effective number of bits of the ADC chip, and SNR is the maximum signal-to-noise ratio of the ADC chip.

[0207] Optionally, the first calculation module 410 is also specifically used for:

[0208] Based on the effective number of bits of the ADC chip, the maximum error of the protected single-point sample value of the ADC chip is calculated using the following formula:

[0209] ±I MAX These are the upper and lower limits for the sampled values;

[0210] In the formula, ε noise The maximum error of a single-point sampled value is protected by the ADC chip; N is the effective number of bits of the ADC chip.

[0211] Considering the error caused by the current transformer in the relay protection device, the output value of the ADC chip is calculated using the following formula:

[0212] i=K trans (I(n)+ε T )+ε noise ;

[0213] In the formula, i is the output value of the ADC chip; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical value of the instantaneous sampled value; ε TThe error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise To protect the ADC chip from the maximum error of a single-point sampled value;

[0214] Based on the output value of the ADC chip, the actual single-point sampled value of the relay protection device is calculated using the following formula:

[0215]

[0216] In the formula, I ADC (n) represents the actual single-point sampling value of the relay protection device; K trans The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; I(n) is the theoretical sampling value of the relay protection device; ε T The error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device; ε noise This is to protect the ADC chip from the maximum error of a single-point sampled value.

[0217] Optionally, the second computing module 420 is specifically used for:

[0218] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the actual single-point sampled value of the relay protection device:

[0219] i ADC =F[I ADC (n)];

[0220] In the formula, i ADC This refers to the actual calculated value of the relay protection device; I ADC (n) represents the actual single-point sampled value of the relay protection device; F[X] represents the Fourier transform algorithm used.

[0221] Optionally, the third computing module 430 is specifically used for:

[0222] Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the sampled theoretical value of the relay protection device:

[0223] i F =F[I(n)];

[0224] In the formula, i F denoted as , where is the theoretical value of the sampling of the relay protection device; I(n) is the theoretical value of the sampling of the relay protection device; F[X] is the Fourier transform algorithm used.

[0225] Optionally, the fourth calculation module 440 is specifically used for:

[0226] Based on the actual and theoretical calculated values ​​of the relay protection device, the ADC sampling error of the relay protection device is calculated using the following formula:

[0227] ε ADC =i ADC -i F ;

[0228] In the formula, ε ADC For the ADC sampling error of the relay protection device; i ADC The actual calculated value for the relay protection device; i F These are the theoretical values ​​sampled by the relay protection device;

[0229] Based on the original signal value and theoretical calculation value of the relay protection device, the filtering algorithm error of the relay protection device is calculated using the following formula:

[0230] ε F =i F -i(t);

[0231] In the formula, ε F For the filtering algorithm error of the relay protection device; i F t is the theoretical value of the sampling of the relay protection device; i(t) is the original signal value of the relay protection device.

[0232] Optionally, the accuracy evaluation module 450 is specifically used for:

[0233] When the sampled value is AC current, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0234] MAX(ε F +ε ADC )≤±0.02I n or

[0235] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC I represents the ADC sampling error of the relay protection device; i(t) represents the original signal value of the relay protection device; I n The rated value of the sampling current for the relay protection device;

[0236] When the sampled value is AC voltage, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements:

[0237] MAX(ε F +ε ADC )≤±0.02U n or

[0238] In the formula, MAX(ε) F +ε ADC The absolute error of the relay protection device's operating value is denoted as . ε represents the relative error of the operating value of the relay protection device. F For the filtering algorithm error of the relay protection device; ε ADC U is the ADC sampling error of the relay protection device; u(t) is the original voltage value of the relay protection device; U n This refers to the rated value of the sampling voltage for the relay protection device.

[0239] The relay protection accuracy evaluation device 400 considering the error of ADC chip and filtering algorithm in an embodiment of the present invention corresponds to the relay protection accuracy evaluation method 100 considering the error of ADC chip and filtering algorithm in another embodiment of the present invention, and will not be described again here.

[0240] Exemplary electronic devices

[0241] Figure 5 This is the structure of an electronic device provided in an exemplary embodiment of the present invention. The electronic device may be either or both of a first device and a second device, or a standalone device independent of them, which may communicate with the first device and the second device to receive acquired input signals from them. Figure 5 A block diagram of an electronic device according to an embodiment of the present invention is illustrated. Figure 5 As shown, the electronic device 50 includes one or more processors 51 and memory 52.

[0242] The processor 51 may be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0243] The memory 52 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 51 may execute the program instructions to implement the methods for information mining of historical change records and / or other desired functions of the software programs of the various embodiments of the present invention described above. In one example, the electronic device may also include an input device 53 and an output device 54, these components being interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0244] In addition, the input device 53 may also include, for example, a keyboard, a mouse, etc.

[0245] The output device 54 can output various information to the outside. The output device 54 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0246] Of course, for the sake of simplicity, Figure 5 Only some of the components of the electronic device relevant to the present invention are shown, omitting components such as buses, input / output interfaces, etc. In addition, the electronic device may include any other suitable components depending on the specific application.

[0247] Exemplary computer program products and computer-readable storage media

[0248] In addition to the methods and devices described above, embodiments of the present invention may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps of the methods for information mining of historical change records according to various embodiments of the present invention as described in the "Exemplary Methods" section of this specification.

[0249] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of the present invention. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0250] Furthermore, embodiments of the present invention may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps of the methods for information mining of historical change records according to various embodiments of the present invention as described in the "Exemplary Methods" section above.

[0251] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0252] The basic principles of the present invention have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in the present invention are merely examples and not limitations, and should not be considered as essential features of each embodiment of the present invention. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the present invention to the necessity of employing the aforementioned specific details.

[0253] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For system embodiments, since they largely correspond to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0254] The block diagrams of devices, systems, devices, and systems involved in this invention are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, systems, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0255] The methods and systems of the present invention may be implemented in many ways. For example, they may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above-described order of steps for the methods is for illustrative purposes only, and the steps of the methods of the present invention are not limited to the order specifically described above unless otherwise specifically stated. Furthermore, in some embodiments, the present invention may also be implemented as a program recorded on a recording medium, the program comprising machine-readable instructions for implementing the methods according to the present invention. Thus, the present invention also covers recording media storing programs for performing the methods according to the present invention.

[0256] It should also be noted that in the systems, apparatus, and methods of the present invention, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered equivalents of the present invention. The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the invention. Therefore, the invention is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0257] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the invention to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations therein.

Claims

1. A method for evaluating the accuracy of relay protection considering the errors of ADC chips and filtering algorithms, characterized in that, include: Calculate the actual single-point sampled value of the relay protection device; Calculate the actual calculated value of the relay protection device based on the actual single-point sampling value of the relay protection device; Calculate the theoretical values ​​of the relay protection device based on the sampled theoretical values. Based on the original signal value, actual calculated value, and theoretical calculated value of the relay protection device, calculate the ADC sampling error and filtering algorithm error of the relay protection device, including: Based on the actual and theoretical calculated values ​​of the relay protection device, the ADC sampling error of the relay protection device is calculated using the following formula: ； In the formula, This refers to the ADC sampling error of the relay protection device. This refers to the actual calculated value of the relay protection device; These are the theoretical values ​​sampled by the relay protection device; Based on the original signal value and theoretical calculation value of the relay protection device, the filtering algorithm error of the relay protection device is calculated using the following formula: ； In the formula, This refers to the filtering algorithm error of the relay protection device; These are the theoretical values ​​sampled by the relay protection device; This is the original signal value of the relay protection device; Based on the ADC sampling error and filtering algorithm error, and in conjunction with the relay protection accuracy standards, evaluate whether the errors generated by the ADC chip and filtering algorithm applied to the relay protection algorithm meet the standard requirements, including: When the sampled value is AC current, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements: or ; In the formula, This refers to the absolute error of the relay protection device's operating value. The relative error of the operating value of the relay protection device; This refers to the filtering algorithm error of the relay protection device; This refers to the ADC sampling error of the relay protection device. This is the original signal value of the relay protection device; The rated value of the sampling current for the relay protection device; When the sampled value is AC voltage, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements: or ; In the formula, This refers to the absolute error of the relay protection device's operating value. The relative error of the operating value of the relay protection device; This refers to the filtering algorithm error of the relay protection device; This refers to the ADC sampling error of the relay protection device. This is the original voltage value of the relay protection device; This refers to the rated value of the sampling voltage for the relay protection device.

2. The method according to claim 1, characterized in that, Calculate the actual single-point sampled value of the relay protection device, including: Calculate the effective number of bits of the ADC chip; Based on the effective number of bits of the ADC chip and considering the error caused by the current transformer in the relay protection device, calculate the actual single-point sampling value of the relay protection device.

3. The method according to claim 2, characterized in that, The effective number of bits N of the ADC chip is calculated using the following formula: ； In the formula, N is the effective number of bits of the ADC chip, and SNR is the maximum signal-to-noise ratio of the ADC chip.

4. The method according to claim 3, characterized in that, Based on the effective number of bits of the ADC chip, and considering the error caused by the current transformer within the relay protection device, calculate the actual single-point sampled value of the relay protection device, including: Based on the effective number of bits of the ADC chip, the maximum error of the protected single-point sample value of the ADC chip is calculated using the following formula: ； In the formula, The maximum error of a single-point sampled value is protected by the ADC chip; N is the effective number of bits of the ADC chip. These are the upper and lower limits for the sampled values; Considering the error caused by the current transformer in the relay protection device, the output value of the ADC chip is calculated using the following formula: ； In the formula, This refers to the output value of the ADC chip. The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; This is the theoretical value of the instantaneous sampled value; This error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device. To protect the ADC chip from the maximum error of a single-point sampled value; Based on the output value of the ADC chip, the actual single-point sampled value of the relay protection device is calculated using the following formula: ； In the formula, This represents the actual single-point sampled value of the relay protection device; The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; These are the theoretical values ​​sampled by the relay protection device; This error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device. This is to protect the ADC chip from the maximum error of a single-point sampled value.

5. The method according to claim 1, characterized in that, Based on the actual single-point sampling values ​​of the relay protection device, calculate the actual calculated values ​​of the relay protection device, including: Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the actual single-point sampled value of the relay protection device: ； In the formula, This refers to the actual calculated value of the relay protection device; This represents the actual single-point sampled value of the relay protection device; The Fourier transform algorithm used is shown.

6. The method according to claim 1, characterized in that, Based on the sampled theoretical values ​​of the relay protection device, calculate the theoretical calculated values ​​of the relay protection device, including: Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the sampled theoretical value of the relay protection device: ； In the formula, These are the theoretical values ​​sampled by the relay protection device; These are the theoretical values ​​sampled by the relay protection device; The Fourier transform algorithm used is shown.

7. A relay protection accuracy evaluation device considering the errors of ADC chips and filtering algorithms, characterized in that, include: The first calculation module is used to calculate the actual single-point sampled value of the relay protection device; The second calculation module is used to calculate the actual calculated value of the relay protection device based on the actual single-point sampling value of the relay protection device. The third calculation module is used to calculate the theoretical value of the relay protection device based on the sampled theoretical value of the relay protection device; The fourth calculation module is used to calculate the ADC sampling error and filtering algorithm error of the relay protection device based on the original signal value, actual calculated value, and theoretical calculated value. Specifically, it is used for: Based on the actual and theoretical calculated values ​​of the relay protection device, the ADC sampling error of the relay protection device is calculated using the following formula: ； In the formula, This refers to the ADC sampling error of the relay protection device. This refers to the actual calculated value of the relay protection device; These are the theoretical values ​​sampled by the relay protection device; Based on the original signal value and theoretical calculation value of the relay protection device, the filtering algorithm error of the relay protection device is calculated using the following formula: ； In the formula, This refers to the filtering algorithm error of the relay protection device; These are the theoretical values ​​sampled by the relay protection device; This is the original signal value of the relay protection device; The accuracy evaluation module is used to evaluate whether the errors generated by the ADC chip and filtering algorithm in the relay protection algorithm meet the standard requirements, based on the ADC sampling error and filtering algorithm error, and in accordance with the relay protection accuracy standard requirements. Specifically, it is used for: When the sampled value is AC current, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements: or ; In the formula, This refers to the absolute error of the relay protection device's operating value. The relative error of the operating value of the relay protection device; This refers to the filtering algorithm error of the relay protection device; This refers to the ADC sampling error of the relay protection device. This is the original signal value of the relay protection device; The rated value of the sampling current for the relay protection device; When the sampled value is AC voltage, based on the ADC sampling error and the filtering algorithm error, the following formula is used to evaluate whether the error generated by the ADC chip and filtering algorithm when applied to the relay protection algorithm meets the standard requirements: or ; In the formula, This refers to the absolute error of the relay protection device's operating value. The relative error of the operating value of the relay protection device; This refers to the filtering algorithm error of the relay protection device; This refers to the ADC sampling error of the relay protection device. This is the original voltage value of the relay protection device; This refers to the rated value of the sampling voltage for the relay protection device.

8. The apparatus according to claim 7, characterized in that, The first calculation module is specifically used for: Calculate the effective number of bits of the ADC chip; Based on the effective number of bits of the ADC chip and considering the error caused by the current transformer in the relay protection device, calculate the actual single-point sampling value of the relay protection device.

9. The apparatus according to claim 8, characterized in that, The first calculation module is also specifically used to calculate the effective number of bits N of the ADC chip using the following formula: ； In the formula, N is the effective number of bits of the ADC chip, and SNR is the maximum signal-to-noise ratio of the ADC chip.

10. The apparatus according to claim 9, characterized in that, The first calculation module is also specifically used for: Based on the effective number of bits of the ADC chip, the maximum error of the protected single-point sample value of the ADC chip is calculated using the following formula: ； In the formula, The maximum error of a single-point sampled value is protected by the ADC chip; N is the effective number of bits of the ADC chip. These are the upper and lower limits for the sampled values; Considering the error caused by the current transformer in the relay protection device, the output value of the ADC chip is calculated using the following formula: ； In the formula, This refers to the output value of the ADC chip. The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; This is the theoretical value of the instantaneous sampled value; This error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device. To protect the ADC chip from the maximum error of a single-point sampled value; Based on the output value of the ADC chip, the actual single-point sampled value of the relay protection device is calculated using the following formula: ； In the formula, This represents the actual single-point sampled value of the relay protection device; The combined transformation ratio of the current transformer and analog amplifier circuit within the relay protection device; These are the theoretical values ​​sampled by the relay protection device; This error is caused by the combined effect of the current transformer and analog amplifier circuit within the relay protection device. This is to protect the ADC chip from the maximum error of a single-point sampled value.

11. The apparatus according to claim 7, characterized in that, The second calculation module is specifically used for: Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the actual single-point sampled value of the relay protection device: ； In the formula, This refers to the actual calculated value of the relay protection device; This represents the actual single-point sampled value of the relay protection device; The Fourier transform algorithm used is shown.

12. The apparatus according to claim 7, characterized in that, The third calculation module is specifically used for: Based on the type of relay protection device, the corresponding Fourier transform algorithm is adopted, and the actual calculated value of the relay protection device is calculated using the following formula based on the sampled theoretical value of the relay protection device: ； In the formula, These are the theoretical values ​​sampled by the relay protection device; These are the theoretical values ​​sampled by the relay protection device; The Fourier transform algorithm used is shown.

13. A computer-readable storage medium, characterized in that, The storage medium stores a computer program for performing the method described in any one of claims 1-6.

14. An electronic device, characterized in that, The electronic device includes: processor; Memory used to store the processor's executable instructions; The processor is configured to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1-6.

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