Multi-channel data frequency calculation optimization method

Abstract

The invention discloses a multi-channel data frequency calculation optimization method, and relates to the technical field of power systems. The method comprises the following steps of: setting interval duration T of data sampling interruption according to frequency characteristics of a sampling object, setting a corresponding position weight and an amplitude weight for each sampling channel by combining a channel sampling value and a channel position, and drawing a sampling waveform curve of each sampling channel according to the sampling value of each sampling channel, calculating a sampling data frequency value of each sampling channel at the current time point according to the sampling waveform curve of each sampling channel, and calculating a multi-channel data frequency comprehensive value P at the current time according to the position weight and the amplitude weight of each channel and the sampling data frequency value of the current time point; and correcting the interval time T of data sampling interruption according to a calculation result.

Description

Technical Field

[0001] The invention relates to the technology of electric power system, and in particular to the technology of a multi-channel data frequency calculation optimization method. Background Art

[0002] The frequency of voltage and current data in the power system is around 50HZ or 60HZ. To calculate its frequency, it is necessary to collect multiple data points in one cycle.

[0003] When there are multiple data objects, the acquisition device needs to have multi-channel data acquisition capabilities. When performing frequency calculations on each channel, it will be found that there is a certain deviation in the frequency value. Due to the existence of frequency deviations in each channel, the frequency cannot be accurately selected during calculation, making it difficult to accurately capture the maximum and minimum values ​​of the data, resulting in relatively low data acquisition accuracy, which affects the accuracy of automatic control of the equipment. Summary of the invention

[0004] In view of the defects existing in the above-mentioned prior art, the technical problem to be solved by the present invention is to provide a multi-channel data frequency calculation optimization method which can improve the data acquisition accuracy and enhance the accuracy of automatic control of equipment.

[0005] In order to solve the above technical problems, the present invention provides a multi-channel data frequency calculation optimization method, which is characterized by the following specific steps:

[0006] 1) According to the frequency characteristics of the sampling object, the interval duration of data sampling interruption is set as follows:

[0007] T=1 / F / (N+1) / D

[0008] In the formula, T is the time interval of data sampling interruption, F is the frequency of the sampling object, N is the harmonic number of the sampling object, D is a preset sampling constant value greater than 2, and the sampling object refers to the sampled voltage and current;

[0009] Set a position weight array W with m components and an amplitude weight array K with m components, where m is the number of sampling channels, and each sampling channel corresponds to a component in the position weight array W and a component in the amplitude weight array K;

[0010] 2) Set the value of each element in the position weight array W to:

[0011]

[0012] Where W i is the value of the i-th component in the position weight array W;

[0013] Set the values ​​of each component in the amplitude weight array K to:

[0014]

[0015] In the formula, K i is the value of the i-th component in the amplitude weight array K, vi is the maximum sampling value of the i-th sampling channel in the most recent 1 / F time period, vj is the maximum sampling value of the j-th sampling channel in the most recent 1 / F time period, and fabs is the absolute value function;

[0016] 3) Obtain a sampling value from m sampling channels every time interval T, and draw a sampling waveform curve of each sampling channel according to the sampling value of each sampling channel, and then calculate the sampling data frequency value of each sampling channel at the current time point according to the sampling waveform curve of each sampling channel. The specific calculation formula is:

[0017] H i =1 / 2 / (t 1.i -t 0.i )

[0018] In the formula, H i is the sampling data frequency value of the i-th sampling channel at the current time point, (t 1.i -t 0.i ) is the time difference between the two zero-crossing points closest to the current time point on the sampling waveform curve of the i-th sampling channel;

[0019] 4) Calculate the comprehensive value P of the multi-channel data frequency at the current time. The specific calculation formula is:

[0020]

[0021] 5) Set T = 1 / P, wait for T time, set t = t + T, and then go to step 2).

[0022] The multi-channel data frequency calculation optimization method provided by the present invention calculates the calculation frequency of each channel by assigning different weights in combination with the channel value and the channel position, can correct the sampling period in real time, reduce the loss of sampling data when high-order harmonics suddenly change, improve data acquisition accuracy, and enhance the accuracy of automatic control of equipment. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments, but this embodiment is not intended to limit the present invention. All similar structures and similar variations of the present invention should be included in the protection scope of the present invention. The commas in the present invention represent the relationship of and, and the English letters in the present invention are case-sensitive.

[0024] A multi-channel data frequency calculation optimization method provided by an embodiment of the present invention is characterized in that the specific steps are as follows:

[0025] 1) According to the frequency characteristics of the sampling object, the interval duration of data sampling interruption is set as follows:

[0026] T=1 / F / (N+1) / D

[0027] In the formula, T is the time interval of data sampling interruption, F is the frequency of the sampling object, the power frequency of the grid voltage data is usually 50HZ, N is the harmonic number of the sampling object, the typical value of N is 1 to 30, D is a preset sampling constant value greater than 2, the typical value of D is 4, and the sampling object refers to the sampled voltage and current;

[0028] Set a position weight array W with m components and an amplitude weight array K with m components, where m is the number of sampling channels (also the number of sampling objects), and each sampling channel corresponds to a component in the position weight array W and a component in the amplitude weight array K;

[0029] 2) Set the value of each element in the position weight array W to:

[0030]

[0031] Where W i is the value of the i-th component in the position weight array W;

[0032] Set the values ​​of each component in the amplitude weight array K to:

[0033]

[0034] In the formula, K i is the value of the i-th component in the amplitude weight array K, vi is the maximum sampling value of the i-th sampling channel in the most recent 1 / F time period, vj is the maximum sampling value of the j-th sampling channel in the most recent 1 / F time period, and fabs is the absolute value function;

[0035] 3) Obtain a sampling value from m sampling channels every time interval T, and draw a sampling waveform curve of each sampling channel according to the sampling value of each sampling channel, and then calculate the sampling data frequency value of each sampling channel at the current time point according to the sampling waveform curve of each sampling channel. The specific calculation formula is:

[0036] H i =1 / 2 / (t 1.i -t 0.i )

[0037] In the formula, H i is the sampling data frequency value of the i-th sampling channel at the current time point, (t 1.i -t0.i ) is the time difference between the two zero-crossing points closest to the current time point on the sampling waveform curve of the i-th sampling channel, and the time difference is half a period of the sampling waveform curve;

[0038] 4) Calculate the comprehensive value P of the multi-channel data frequency at the current time. The specific calculation formula is:

[0039]

[0040] 5) Set T = 1 / P, wait for T time, set t = t + T, and then go to step 2).

Claims

1. A multi-channel data frequency calculation optimization method, characterized in that: The specific steps are as follows: 1) According to the frequency characteristics of the sampling object, the interval duration of data sampling interruption is set as follows: T=1 / F / (N+1) / D In the formula, T is the time interval of data sampling interruption, F is the frequency of the sampling object, N is the harmonic number of the sampling object, D is a preset sampling constant value greater than 2, and the sampling object refers to the sampled voltage and current; Set a position weight array W with m components and an amplitude weight array K with m components, where m is the number of sampling channels, and each sampling channel corresponds to a component in the position weight array W and a component in the amplitude weight array K; 2) Set the value of each element in the position weight array W to: Where W i is the value of the i-th component in the position weight array W; Set the values ​​of each component in the amplitude weight array K to: In the formula, K i is the value of the i-th component in the amplitude weight array K, vi is the maximum sampling value of the i-th sampling channel in the most recent 1 / F time period, vj is the maximum sampling value of the j-th sampling channel in the most recent 1 / F time period, and fabs is the absolute value function; 3) Obtain a sampling value from m sampling channels every time interval T, and draw a sampling waveform curve of each sampling channel according to the sampling value of each sampling channel, and then calculate the sampling data frequency value of each sampling channel at the current time point according to the sampling waveform curve of each sampling channel. The specific calculation formula is: H i =1 / 2 / (t 1.i -t 0.i ) In the formula, H i is the sampling data frequency value of the i-th sampling channel at the current time point, (t 1.i -t 0.i ) is the time difference between the two zero-crossing points closest to the current time point on the sampling waveform curve of the i-th sampling channel; 4) Calculate the comprehensive value P of the multi-channel data frequency at the current time. The specific calculation formula is: 5) Set T = 1 / P, wait for T time, set t = t + T, and then go to step 2).

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