Method, device and computer equipment for rapid detection of three-phase imbalance in distribution network

Abstract

The present application relates to a method, device, computer equipment, storage medium and computer program product for rapid detection of three-phase imbalance in a distribution network. The method comprises: obtaining a first preset number of first three-phase current values, the first preset number of first three-phase current values being obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; determining the initial three-phase imbalance of the distribution network under each first three-phase current value condition according to the phase relationship between each first three-phase current value and the three phases; the three phases include phase A, phase B and phase C; determining the three-phase balance result of the distribution network within a preset time length according to all the initial three-phase imbalances. Since the present application does not need to obtain the three-phase current value of one cycle, but only needs to first obtain the three-phase current value of half a cycle, the amount of data involved in the calculation of the three-phase balance in the present application is smaller than the amount of data involved in the calculation of the three-phase balance in the related art. This reduces the amount of calculation.

Description

Technical Field

[0001] The present application relates to the technical field of distribution networks, and in particular to a method, apparatus, computer equipment, storage medium, and computer program product for rapid detection of three-phase imbalance in a distribution network. Background Art

[0002] Distribution networks face a range of issues, one of the most prominent being three-phase imbalance. This problem is primarily caused by the following: Firstly, during normal power system operation, the load on the distribution network gradually increases without proper planning, resulting in uneven load distribution in both time and space. Secondly, during line reconstruction, personnel fail to distinguish between the three-phase lines and arbitrarily connect loads to a single phase, leading to unbalanced loads across the three-phase lines of the distribution network. Therefore, analyzing three-phase imbalance is crucial. An excellent three-phase imbalance analysis method can quickly and accurately determine the degree of three-phase imbalance, helping to reduce power loss, prevent zero-sequence currents in distribution transformers, ensure the safe operation of electrical equipment, and improve motor efficiency.

[0003] In the related art, when performing three-phase balance calculations, it is necessary to collect three-phase electrical quantity data of one cycle, and then use the full-wave Fourier algorithm to perform relatively complex analysis and calculation on the three-phase electrical quantity data of one cycle to obtain the amplitude and phase of each of the three phases. Then, based on the amplitude and phase of each of the three phases, the three-phase imbalance of the cycle is obtained. Finally, based on the three-phase imbalance, it is possible to determine whether the three phases of the cycle are balanced. This leads to the problem of large computational complexity in the method of calculating three-phase balance using related technologies, where the three-phase electrical quantity data includes current. Summary of the Invention

[0004] Based on this, it is necessary to provide a method, device, computer equipment, computer-readable storage medium and computer program product for quickly detecting three-phase imbalance in a distribution network, which can reduce the amount of calculation when calculating three-phase balance, in order to address the above technical problems.

[0005] In a first aspect, the present application provides a method for quickly detecting three-phase imbalance in a distribution network. The method comprises:

[0006] Obtaining a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency;

[0007] Determining an initial three-phase imbalance of the distribution network under each first three-phase current value condition according to each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C;

[0008] Based on all initial three-phase imbalances, the three-phase balance result of the distribution network within a preset time length is determined; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0009] In one embodiment, each first three-phase current value includes a current value of phase A, a current value of phase B, and a current value of phase C. Determining an initial three-phase imbalance of the power distribution network under each first three-phase current value condition based on a phase relationship between each first three-phase current value and the three phases includes:

[0010] Obtaining a first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees to obtain a first product corresponding to each first three-phase current value;

[0011] Obtaining a second product between the current value of phase C in each of the first three-phase current values and the cosine value of 240 degrees, to obtain a second product corresponding to each of the three-phase current values;

[0012] Obtain the sum of the current value of phase A in each first three-phase current value, the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and use the sum as the initial three-phase imbalance of the distribution network under each first three-phase current value condition.

[0013] In one embodiment, determining a three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances includes:

[0014] According to the matching result between each initial three-phase unbalance degree and the preset range, determining the number of initial three-phase unbalance degrees that match the preset range among all the initial three-phase unbalance degrees;

[0015] obtaining a ratio between the quantity and a first preset quantity;

[0016] If the ratio is greater than a preset threshold, the three-phase balance result is determined to be that the three phases are in a balanced state;

[0017] If the ratio is not greater than the preset threshold, it is determined that the three-phase balance result is that the three phases are in an unbalanced state.

[0018] In one embodiment, after determining that the three-phase balance result is that the three phases are in an unbalanced state, the method further includes:

[0019] Obtaining a second preset number of second three-phase current values, where the second preset number of second three-phase current values are obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number;

[0020] Determine the three-phase amplitudes within a quarter cycle based on all second three-phase current values; the three-phase amplitudes include the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C;

[0021] According to the three-phase amplitude, the three-phase imbalance of the distribution network is obtained;

[0022] According to the three-phase imbalance degree, the distribution network is adjusted for three-phase imbalance.

[0023] In one embodiment, determining the three-phase amplitudes within a quarter cycle based on all second three-phase current values includes:

[0024] Obtaining the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value;

[0025] Determine the effective current value of phase A within a quarter cycle based on the square of the current value of phase A among all the second three-phase current values and a second preset number;

[0026] According to the effective value of the current of phase A, determine the current amplitude of phase A within a quarter cycle;

[0027] determining an effective current value of phase B within a quarter cycle based on the square of the current value of phase B among all the second three-phase current values and a second preset number;

[0028] According to the effective value of the current of phase B, determine the current amplitude of phase B within a quarter cycle;

[0029] determining an effective current value of phase C within a quarter cycle based on the square of the current value of phase C among all the second three-phase current values and a second preset number;

[0030] The current amplitude of phase C within a quarter cycle is determined based on the effective value of the current of phase C.

[0031] In one embodiment, obtaining the three-phase imbalance of the distribution network according to the three-phase amplitudes includes:

[0032] Obtain an average current amplitude according to the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C in the three-phase amplitudes;

[0033] The three-phase imbalance of the distribution network is determined based on the maximum current amplitude and the average current amplitude among the three-phase amplitudes.

[0034] In a second aspect, the present application also provides a device for rapid detection of three-phase imbalance in a distribution network. The device comprises:

[0035] an acquisition module, configured to acquire a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency;

[0036] A first determining module is configured to determine an initial three-phase imbalance of the distribution network under each first three-phase current value condition based on each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C;

[0037] The second determination module is used to determine the three-phase balance result of the distribution network within a preset time length based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0038] In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are performed:

[0039] Obtaining a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency;

[0040] Determining an initial three-phase imbalance of the distribution network under each first three-phase current value condition according to each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C;

[0041] Based on all initial three-phase imbalances, the three-phase balance result of the distribution network within a preset time length is determined; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0042] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the following steps:

[0043] Obtaining a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency;

[0044] Determining an initial three-phase imbalance of the distribution network under each first three-phase current value condition according to each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C;

[0045] Based on all initial three-phase imbalances, the three-phase balance result of the distribution network within a preset time length is determined; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0046] In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the following steps:

[0047] Obtaining a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency;

[0048] Determining an initial three-phase imbalance of the distribution network under each first three-phase current value condition according to each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C;

[0049] Based on all initial three-phase imbalances, the three-phase balance result of the distribution network within a preset time length is determined; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0050] The above-mentioned method, device, computer equipment, storage medium and computer program product for rapid detection of three-phase imbalance in the distribution network do not need to obtain the three-phase current value of one cycle, but only need to first obtain the three-phase current value of half a cycle. Therefore, the amount of data involved in the calculation of the three-phase balance in the present application is smaller than the amount of data involved in the calculation of the three-phase balance in the related art. Since the present application, after obtaining the three-phase current value of half a cycle, does not need to use a full-wave Fourier algorithm to perform a relatively complex analysis and calculation on the three-phase current value of half a cycle to obtain the amplitude and phase of each of the three phases, and then obtain the three-phase imbalance of the cycle based on the amplitude and phase of each of the three phases, but only needs to use a simple algorithm to analyze the phase relationship between each first three-phase current value and the three phases, determine the initial three-phase imbalance of the distribution network under each first three-phase current value condition, and finally determine the three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances. Therefore, the algorithm of the present application is simpler than the algorithm for calculating three-phase balance in the related art. Furthermore, the present application reduces the amount of calculation by reducing the amount of data involved in the calculation and reducing the complexity of the algorithm used to calculate the three-phase balance, thereby improving the efficiency of determining the three-phase balance result of the distribution network within a preset time period. Moreover, since the present application does not need to use a complex full-wave Fourier algorithm to calculate the three-phase balance, the hardware requirements for the intelligent distribution box are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 11 is a flow chart of a method for quickly detecting three-phase imbalance in a power distribution network according to an embodiment;

[0052] Figure 2 1 is a flow chart of a method for quickly detecting three-phase imbalance in a power distribution network according to an embodiment;

[0053] Figure 3 1 is a flow chart of a method for quickly detecting three-phase imbalance in a power distribution network according to another embodiment;

[0054] Figure 4 This is a structural block diagram of a device for rapid detection of three-phase imbalance in a power distribution network according to one embodiment;

[0055] Figure 5 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0057] It is understood that the terms "first," "second," and the like used herein may be used to describe various technical terms, but unless otherwise specified, these technical terms are not limited by these terms. These terms are used solely to distinguish one technical term from another. For example, the first predetermined quantity and the second predetermined quantity may be the same or different without departing from the scope of this application.

[0058] Distribution networks face a range of issues, one of the most prominent being three-phase imbalance. This problem is primarily caused by the following: Firstly, during normal power system operation, the load on the distribution network gradually increases without proper planning, resulting in uneven load distribution in both time and space. Secondly, during line reconstruction, personnel fail to distinguish between the three-phase lines and arbitrarily connect loads to a single phase, leading to unbalanced loads across the three-phase lines of the distribution network. Therefore, analyzing three-phase imbalance is crucial. An excellent three-phase imbalance analysis method can quickly and accurately determine the degree of three-phase imbalance, helping to reduce power loss, prevent zero-sequence currents in distribution transformers, ensure the safe operation of electrical equipment, and improve motor efficiency.

[0059] In the related art, when performing three-phase balance calculations, it is necessary to collect three-phase electrical quantity data of one cycle, and then use the full-wave Fourier algorithm to perform relatively complex analysis and calculation on the three-phase electrical quantity data of one cycle to obtain the amplitude and phase of each of the three phases. Then, based on the amplitude and phase of each of the three phases, the three-phase imbalance of the cycle is obtained. Finally, based on the three-phase imbalance, it is possible to determine whether the three phases of the cycle are balanced. This leads to the problem of large computational complexity in the method of calculating three-phase balance using related technologies, where the three-phase electrical quantity data includes current.

[0060] In response to the problems existing in the above-mentioned related technologies, an embodiment of the present invention provides a method for quickly detecting three-phase imbalance in a distribution network. The method can be applied to a server, a terminal, or a system including a terminal and a server, and is implemented through the interaction between the terminal and the server. Among them, the server can be implemented as an independent server or a server cluster composed of multiple servers. The terminal can be, but is not limited to, various personal computers, laptops, smart phones, tablet computers, Internet of Things devices, portable wearable devices and smart distribution boxes. The Internet of Things devices can be smart speakers, smart TVs, smart air conditioners, smart car-mounted devices, etc. Portable wearable devices can be smart watches, smart bracelets, head-mounted devices, etc. It should be noted that the quantities of "multiple" and the like mentioned in the embodiments of this application all refer to the quantity of "at least two", for example, "multiple" refers to "at least two".

[0061] In one embodiment, Figure 1 As shown, a method for quickly detecting three-phase imbalance in a distribution network is provided. This embodiment uses the method applied to an intelligent distribution box as an example. The method includes the following steps:

[0062] 102. Obtain a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling currents of the distribution network within half a cycle based on a first preset sampling frequency.

[0063] For ease of understanding, in power systems, three-phase imbalance is generally caused by load imbalance. Since the three-phase voltage output by the transformer in the distribution network generally meets the conditions for three-phase balance, the manifestation of three-phase imbalance is mainly manifested through current. The imbalance of the three-phase load causes the three-phase current to be unbalanced, and three-phase imbalance generally means that the three-phase current does not meet the conditions. Therefore, this application determines the three-phase balance result of the distribution network based on the three-phase current values.

[0064] Among them, in the related art, when performing three-phase balance calculation, it is necessary to collect three-phase electrical quantity data of one cycle. It can be understood that in order to ensure that the number of the first three-phase current values obtained in this embodiment is not higher than the number of three-phase electrical quantity data collected for one cycle in the related art, the first preset sampling frequency can be the same as the sampling frequency used in the related art to collect three-phase electrical quantity data of one cycle, or it can be lower than the sampling frequency used in the related art to collect three-phase electrical quantity data of one cycle. The first preset number is positively correlated with the first preset sampling frequency. The higher the first preset sampling frequency, the larger the first preset number. The value of the first preset number can be determined according to the actual application situation. The specific value of the first preset number can be 10, or it can be a value greater than 10. This embodiment of the present application does not specifically limit this. It should be noted that the duration corresponding to one cycle can be 0.02S, and correspondingly, the duration corresponding to half a cycle can be 0.01S.

[0065] Each first three-phase current value includes a current value of phase A, a current value of phase B, and a current value of phase C.

[0066] 104. Determine the initial three-phase imbalance of the distribution network under each first three-phase current value condition based on each first three-phase current value and the phase relationship between the three phases; the three phases include phase A, phase B, and phase C.

[0067] The phase difference between two adjacent phases in the three phases can be 120°.

[0068] Specifically, step 104 may include: obtaining the third product between the current value of phase C in each first three-phase current value and the cosine value of 120 degrees, to obtain the third product corresponding to each first three-phase current value; obtaining the fourth product between the current value of phase A in each first three-phase current value and the cosine value of 240 degrees, to obtain the fourth product corresponding to each three-phase current value; obtaining the current value of phase B in each first three-phase current value, the third product corresponding to each first three-phase current value, and the fourth product corresponding to each first three-phase current value, and using the sum as the initial three-phase imbalance of the distribution network under each first three-phase current value condition.

[0069] Step 104 may also include: obtaining the fifth product between the current value of phase A in each first three-phase current value and the cosine value of 120 degrees, to obtain the fifth product corresponding to each first three-phase current value; obtaining the sixth product between the current value of phase B in each first three-phase current value and the cosine value of 240 degrees, to obtain the sixth product corresponding to each three-phase current value; obtaining the current value of phase C in each first three-phase current value, the fifth product corresponding to each first three-phase current value, and the sixth product corresponding to each first three-phase current value, and using the sum as the initial three-phase imbalance of the distribution network under each first three-phase current value condition.

[0070] 106. Determine a three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time period includes a time period corresponding to half a cycle.

[0071] Among them, the preset time length can be greater than the time length corresponding to half a cycle. Specifically, the preset time length can be the time length corresponding to one cycle, or the time length corresponding to multiple cycles, and the embodiment of the present application does not make specific limitations on this. For example, the preset time length can be the time length corresponding to 5 cycles, that is, the preset time length can be 0.05S. According to the definition of the preset time length, it can be understood that this embodiment can determine the three-phase balance result of the distribution network within the preset time length only based on the first preset number of first three-phase current values obtained by sampling the current of the distribution network within half a cycle based on the first preset sampling frequency. Compared with the method in the related art that requires collecting three-phase electrical quantity data of one cycle to determine the three-phase balance result, the amount of data in this embodiment is less.

[0072] For ease of understanding, the time period corresponding to the preset duration includes the specific meaning of the time period corresponding to half a cycle. For example, the duration corresponding to half a cycle is 0.01S, and the preset duration is 0.02S. Based on the first preset number of first three-phase current values obtained by sampling the distribution network from 0 to 0.01S based on the first preset sampling frequency, the three-phase balance result of the distribution network within 0 to 0.02S can be determined.

[0073] Specifically, step 106 may include: obtaining the number of initial three-phase imbalance degrees that are 0 among all initial three-phase imbalance degrees, and obtaining a ratio between the number and a first preset number; if the ratio is greater than a preset threshold, determining that the three-phase balance result is that the three phases are in a balanced state; if the ratio is not greater than the preset threshold, determining that the three-phase balance result is that the three phases are in an unbalanced state.

[0074] In the above-mentioned method for rapid detection of three-phase imbalance in the distribution network, the intelligent distribution box obtains a first preset number of first three-phase current values, and the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; then, based on the phase relationship between each first three-phase current value and the three phases, the initial three-phase imbalance of the distribution network under each first three-phase current value condition is determined; the three phases include phase A, phase B and phase C; finally, based on all the initial three-phase imbalances, the three-phase balance result of the distribution network within a preset time length can be determined; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle. Since the present application does not need to obtain the three-phase current value of a cycle, but only needs to first obtain the three-phase current value of half a cycle, the amount of data involved in the calculation of the three-phase balance in the present application is smaller than the amount of data involved in the calculation of the three-phase balance in the related art. Since the present application, after obtaining the three-phase current value of half a cycle, does not need to use a full-wave Fourier algorithm to perform a relatively complex analysis and calculation on the three-phase current value of half a cycle to obtain the amplitude and phase of each of the three phases, and then obtain the three-phase imbalance of the cycle based on the amplitude and phase of each of the three phases, but only needs to use a simple algorithm to analyze the phase relationship between each first three-phase current value and the three phases, determine the initial three-phase imbalance of the distribution network under each first three-phase current value condition, and finally determine the three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances. Therefore, the algorithm of the present application is simpler than the algorithm for calculating three-phase balance in the related art. Furthermore, the present application reduces the amount of calculation by reducing the amount of data involved in the calculation and reducing the complexity of the algorithm used to calculate the three-phase balance, thereby improving the efficiency of determining the three-phase balance result of the distribution network within a preset time period. Moreover, since the present application does not need to use a complex full-wave Fourier algorithm to calculate the three-phase balance, the hardware requirements for the intelligent distribution box are reduced.

[0075] In one embodiment, each first three-phase current value includes a current value of phase A, a current value of phase B, and a current value of phase C. Determining an initial three-phase imbalance of the power distribution network under each first three-phase current value condition based on a phase relationship between each first three-phase current value and the three phases includes:

[0076] Obtain the first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees to obtain the first product corresponding to each first three-phase current value; obtain the second product between the current value of phase C in each first three-phase current value and the cosine value of 240 degrees to obtain the second product corresponding to each three-phase current value; obtain the sum of the current value of phase A in each first three-phase current value, the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and use the sum as the initial three-phase imbalance of the distribution network under the condition of each first three-phase current value.

[0077] Specifically, the process of determining the initial three-phase imbalance of the distribution network under each first three-phase current value condition can refer to formula (1):

[0078] α1=i a +i b cos(120°)+i c cos(240°);(1)

[0079] In formula (1), α1 is the initial three-phase unbalance of the distribution network under each first three-phase current value condition, i a is the current value of phase A in each of the first three-phase current values, i b is the current value of phase B in each of the first three-phase current values, i c is the current value of phase C in each of the first three-phase current values.

[0080] In this embodiment, the initial three-phase imbalance of the distribution network under each first three-phase current value condition can be determined by the above formula (1), and the three-phase balance result of the distribution network within a preset time period can be determined based on all the initial three-phase imbalances, thereby reducing the amount of calculation.

[0081] In one embodiment, Figure 2 As shown, based on all initial three-phase imbalances, the three-phase balance result of the distribution network within a preset time period is determined, including:

[0082] 202. Determine the number of initial three-phase unbalance degrees that match the preset range among all initial three-phase unbalance degrees according to the matching result between each initial three-phase unbalance degree and the preset range.

[0083] The matching result is a match or a mismatch. The process of determining the matching result between each initial three-phase imbalance and the preset range may include: for any initial three-phase imbalance, determining whether any initial three-phase imbalance is within the preset range; if so, determining that the matching result between any initial three-phase imbalance and the preset range is a match; if not, determining that the matching result between any initial three-phase imbalance and the preset range is a mismatch.

[0084] In addition, the preset range can be set according to the on-site voltage distribution network conditions.

[0085] The reason why the three-phase balance result is not determined based on the ratio between the number of initial three-phase imbalances that are zero among all initial three-phase imbalances and a first preset number is that, in actual applications, when the intelligent distribution box collects data, the distribution network electrical quantity waveform is not a standard sine wave and contains some harmonic components. In addition, the sampling process may cause some errors, resulting in a large number of initial three-phase imbalances among all initial three-phase imbalances being non-zero. This may lead to the following situation: when the distribution network is actually in a balanced state for a preset time period, the three-phase imbalance of the distribution network is determined to be unbalanced based on the ratio between the number of initial three-phase imbalances that are zero among all initial three-phase imbalances and the first preset number, even when the three-phase imbalance is actually balanced for a preset time period. Therefore, to prevent the three-phase balance result obtained by the intelligent distribution box from being inconsistent with the actual situation, a preset range is set based on the on-site voltage distribution network conditions. As long as the ratio between the number of initial three-phase imbalances that match the preset range among all initial three-phase imbalances and the first preset number is greater than a preset threshold, the three-phase balance result is determined to be balanced.

[0086] 204. Acquire a ratio between the quantity and a first preset quantity.

[0087] 206. If the ratio is greater than a preset threshold, it is determined that the three-phase balance result is that the three phases are in a balanced state.

[0088] The preset threshold value may be set according to the actual application scenario, specifically, it may be 90%, which is not specifically limited in the embodiment of the present application.

[0089] 208. If the ratio is not greater than the preset threshold, it is determined that the three-phase balance result is that the three phases are in an unbalanced state.

[0090] The quantities in steps 204, 206, and 208 refer to the number of initial three-phase unbalance degrees that match the preset range among all initial three-phase unbalance degrees, and the ratios in steps 204, 206, and 208 refer to the ratio between the number of initial three-phase unbalance degrees that match the preset range among all initial three-phase unbalance degrees and the first preset number.

[0091] In this embodiment, the three-phase balance result is determined not based on the ratio between the number of initial three-phase imbalances that are zero among all initial three-phase imbalances and a first preset number, but rather a preset range is set based on the on-site voltage distribution network conditions. As long as the ratio between the number of initial three-phase imbalances that match the preset range among all initial three-phase imbalances and the first preset number is greater than a preset threshold, the three-phase balance result is determined to be in a balanced state. This prevents the three-phase balance result obtained by the intelligent distribution box from being inconsistent with actual conditions, thereby improving the accuracy of the three-phase balance result. Since only the number of initial three-phase imbalances that match the preset range needs to be counted, the three-phase balance result of the distribution network within a preset time period can be determined subsequently, thereby reducing the amount of computation required.

[0092] In one embodiment, after determining that the three-phase balance result is that the three phases are in an unbalanced state, the method further includes:

[0093] A second preset number of second three-phase current values are obtained, where the second preset number of second three-phase current values are obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number.

[0094] The explanation of the second three-phase current value may refer to the explanation of the first three-phase current value in step 102, which will not be repeated here.

[0095] In addition, the second preset sampling frequency can be equal to the first preset sampling frequency, or can be higher than the first preset sampling frequency, as long as the second preset number obtained by sampling the current of the distribution network within a quarter cycle based on the second preset sampling frequency is less than the first preset number. The embodiment itself does not specifically limit this. However, in order to reduce the hardware requirements for the intelligent distribution box, the second preset sampling frequency is usually equal to the first preset sampling frequency. It can be understood that when the second preset sampling frequency is equal to the first preset sampling frequency. For example, the duration corresponding to half a cycle is 0.01S, and the first preset number is 10. Then the duration corresponding to a quarter cycle is 0.005S, and the second preset number is 5.

[0096] The three-phase amplitudes within a quarter cycle are determined based on all the second three-phase current values; the three-phase amplitudes include the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C.

[0097] According to the three-phase amplitudes, the three-phase imbalance of the distribution network is obtained.

[0098] According to the three-phase imbalance degree, the distribution network is adjusted for three-phase imbalance.

[0099] It is understandable that by calculating the three-phase amplitude imbalance, the imbalance of the three phases of the distribution network can be obtained, thereby performing three-phase imbalance adjustment on the distribution network.

[0100] In this embodiment, in the related art, when performing three-phase balance calculation, it is based on the three-phase imbalance to determine whether the three phases of the cycle are balanced. It can be understood that in the related art, the three-phase imbalance needs to be determined when the three phases are in a balanced state or in an unbalanced state, which has a problem of large amount of calculation. However, the present application only needs to determine the three-phase imbalance when the three phases are in an unbalanced state, and there is no need to determine the three-phase imbalance based on the three-phase current value of one cycle, but only needs to determine the three-phase imbalance based on the three-phase current value of a quarter cycle, thereby reducing the amount of calculation.

[0101] In one embodiment, determining the three-phase amplitudes within a quarter cycle based on all second three-phase current values includes:

[0102] Obtain the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value; determine the effective value of the current of phase A within a quarter cycle based on the square of the current value of phase A in all second three-phase current values and a second preset number; determine the current amplitude of phase A within a quarter cycle based on the effective value of the current of phase A.

[0103] For example, the second preset number is n, and the current value of phase A, the current value of phase B, and the current value of phase C in all the second three-phase current values can be respectively shown in the following sequence:

[0104] i a =[i a1 ,i a2 ,…,i aj ,…,i an ];

[0105] i b =[i b1 ,i b2 ,…,i bj ,…,i bn ];

[0106] i c =[i c1 ,i c2 ,…,i cj ,…,i cn ];

[0107] It should be noted that in the above sequence, i a is the current value of phase A among all the second three-phase current values, i b is the current value of phase B among all the second three-phase current values, i cis the current value of phase C among all the second three-phase current values.

[0108] Accordingly, the process of determining the current amplitude of phase A within a quarter cycle can refer to formula (2):

[0109]

[0110] In formula (2), I a is the current amplitude of phase A within a quarter cycle, It is the effective value of the current of phase A within one quarter of the cycle.

[0111] The effective value of the current of phase B within a quarter cycle is determined based on the square of the current value of phase B in all the second three-phase current values and a second preset number; and the current amplitude of phase B within a quarter cycle is determined based on the effective value of the current of phase B.

[0112] Accordingly, the process of determining the current amplitude of phase B within a quarter cycle can refer to formula (3):

[0113]

[0114] In formula (3), I b is the current amplitude of phase B within a quarter cycle, It is the effective value of the current of phase B within one quarter of the cycle.

[0115] The effective value of the current of phase C within a quarter cycle is determined based on the square of the current value of phase C in all the second three-phase current values and a second preset number; and the current amplitude of phase C within a quarter cycle is determined based on the effective value of the current of phase C.

[0116] Accordingly, the process of determining the current amplitude of phase C within a quarter cycle can refer to formula (4):

[0117]

[0118] In formula (4), I c is the current amplitude of phase C within a quarter cycle, It is the effective value of the current of phase C within one quarter of the cycle.

[0119] In one embodiment, obtaining the three-phase imbalance of the distribution network according to the three-phase amplitudes includes:

[0120] An average current amplitude is obtained based on the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C among the three-phase amplitudes.

[0121] Specifically, the process of obtaining the average current amplitude can refer to formula (5):

[0122]

[0123] In formula (5), is the average current amplitude, for I a , I b and I c For the explanation of I, please refer to the above formulas (2), (3) and (4). a , I b and I c The explanation is not repeated here.

[0124] The three-phase imbalance of the distribution network is determined based on the maximum current amplitude and the average current amplitude among the three-phase amplitudes.

[0125] Specifically, the difference between the maximum current amplitude and the average current amplitude among the three-phase amplitudes is obtained, the ratio between the difference and the average current amplitude is obtained, the ratio between the difference and the average current amplitude is converted into a percentage, and the percentage is used as the three-phase imbalance of the distribution network.

[0126] The determination process of the three-phase imbalance can refer to formula (6):

[0127]

[0128] In formula (6), α is the three-phase imbalance of the distribution network, max[I a , I b , I c ] is the largest current amplitude among the three-phase amplitudes, is the average current amplitude.

[0129] In one embodiment, Figure 3 As shown, a method for quickly detecting three-phase imbalance in a distribution network is provided. This embodiment uses the method applied to an intelligent distribution box as an example. The method includes the following steps:

[0130] 302. Obtain a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency;

[0131] 304. Determine an initial three-phase imbalance of the distribution network under each first three-phase current value condition based on each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C;

[0132] 306. Determine a three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time period includes a time period corresponding to half a cycle.

[0133] 308. If the three-phase balance result of the distribution network within the preset time length is that the three phases are in an unbalanced state, then obtain a second preset number of second three-phase current values, the second preset number of second three-phase current values being obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number; based on all the second three-phase current values, determine the three-phase amplitude within a quarter cycle; the three-phase amplitude includes the current amplitude of phase A, the current amplitude of phase B and the current amplitude of phase C; based on the three-phase amplitude, obtain the three-phase imbalance of the distribution network; based on the three-phase imbalance, perform three-phase imbalance adjustment on the distribution network.

[0134] Among them, the explanations of the nouns and steps involved in this embodiment can refer to the explanations of the nouns and steps in the above embodiments, and will not be repeated here.

[0135] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0136] Based on the same inventive concept, embodiments of the present application also provide a device for rapidly detecting three-phase imbalance in a distribution network, for implementing the aforementioned method for rapidly detecting three-phase imbalance in a distribution network. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the device for rapidly detecting three-phase imbalance in a distribution network provided below can be found in the aforementioned method for rapidly detecting three-phase imbalance in a distribution network, and will not be further elaborated here.

[0137] In one embodiment, Figure 4 As shown, a device for rapid detection of three-phase imbalance in a distribution network is provided, comprising: an acquisition module 402, a first determination module 404, and a second determination module 406, wherein:

[0138] An acquisition module 402 is configured to acquire a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the power distribution network within half a cycle based on a first preset sampling frequency;

[0139] A first determining module 404 is configured to determine an initial three-phase imbalance of the power distribution network under each first three-phase current value according to a phase relationship between each first three-phase current value and the three phases, wherein the three phases include phase A, phase B, and phase C;

[0140] The second determination module 406 is used to determine the three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time period includes the time period corresponding to half a cycle.

[0141] In one embodiment, each first three-phase current value includes a current value of phase A, a current value of phase B, and a current value of phase C. The first determining module 404 includes:

[0142] a first acquiring unit, configured to acquire a first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees, to obtain a first product corresponding to each first three-phase current value;

[0143] a second acquiring unit, configured to acquire a second product between the current value of phase C in each of the first three-phase current values and the cosine value of 240 degrees, to obtain a second product corresponding to each of the three-phase current values;

[0144] The third acquisition unit is used to obtain the current value of phase A in each first three-phase current value, the sum of the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and use the sum as the initial three-phase imbalance of the distribution network under each first three-phase current value condition.

[0145] In one embodiment, the second determining module 406 includes:

[0146] a first determining unit, configured to determine the number of initial three-phase unbalance degrees matching the preset range among all the initial three-phase unbalance degrees according to a matching result between each initial three-phase unbalance degree and the preset range;

[0147] a fourth obtaining unit, configured to obtain a ratio between the quantity and a first preset quantity;

[0148] a second determining unit, configured to determine that the three-phase balance result is that the three phases are in a balanced state if the ratio is greater than a preset threshold;

[0149] The third determining unit is configured to determine that the three-phase balance result is that the three phases are in an unbalanced state if the ratio is not greater than a preset threshold.

[0150] In one embodiment, the second determining module 406 further includes:

[0151] a fifth acquiring unit, configured to acquire a second preset number of second three-phase current values, the second preset number of second three-phase current values being obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, the second preset number being less than the first preset number;

[0152] a fourth determining unit, configured to determine three-phase amplitudes within a quarter cycle based on all second three-phase current values; the three-phase amplitudes including the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C;

[0153] a fifth determining unit, configured to obtain a three-phase imbalance degree of the distribution network according to the three-phase amplitudes;

[0154] The regulating unit is used to perform three-phase imbalance regulation on the distribution network according to the three-phase imbalance degree.

[0155] In one embodiment, the fourth determining unit includes:

[0156] a first acquiring subunit, configured to acquire the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value;

[0157] a first determining subunit, configured to determine an effective current value of phase A within a quarter cycle according to the square of the current value of phase A among all the second three-phase current values and a second preset number;

[0158] a second determining subunit, configured to determine a current amplitude of phase A within a quarter cycle according to the effective current value of phase A;

[0159] a third determining subunit, configured to determine an effective current value of phase B within a quarter cycle according to the square of the current value of phase B among all the second three-phase current values and a second preset number;

[0160] a fourth determining subunit, configured to determine a current amplitude of phase B within a quarter cycle according to the effective value of the current of phase B;

[0161] a fifth determining subunit, configured to determine an effective current value of phase C within a quarter cycle according to the square of the current value of phase C among all the second three-phase current values and a second preset number;

[0162] The sixth determining subunit is configured to determine the current amplitude of the C phase within a quarter cycle according to the effective value of the current of the C phase.

[0163] In one embodiment, the fifth determining unit includes:

[0164] A second acquisition subunit is used to obtain an average current amplitude according to the current amplitude of phase A, the current amplitude of phase B and the current amplitude of phase C in the three-phase amplitudes;

[0165] The seventh determining subunit is configured to determine the three-phase imbalance of the distribution network according to the maximum current amplitude and the average current amplitude among the three-phase amplitudes.

[0166] Each module in the aforementioned rapid detection device for three-phase imbalance in a distribution network can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in hardware form, or can be stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each module.

[0167] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 5 As shown. The computer device includes a processor, a memory and a network interface connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data such as a first preset number of first three-phase current values, all initial three-phase imbalances, the three-phase balance results of the distribution network within a preset time length and a second preset number of second three-phase current values. The network interface of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, a method for quickly detecting three-phase imbalance in a distribution network is implemented.

[0168] Those skilled in the art will understand that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0169] In one embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the following steps are implemented: obtaining a first preset number of first three-phase current values, wherein the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; determining the initial three-phase imbalance of the distribution network under each first three-phase current value condition according to the phase relationship between each first three-phase current value and the three phases; the three phases include phase A, phase B and phase C; determining the three-phase balance result of the distribution network within a preset time length according to all the initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0170] In one embodiment, each first three-phase current value includes the current value of phase A, the current value of phase B, and the current value of phase C. When the processor executes the computer program, the following steps are also implemented: obtaining the first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees to obtain the first product corresponding to each first three-phase current value; obtaining the second product between the current value of phase C in each first three-phase current value and the cosine value of 240 degrees to obtain the second product corresponding to each three-phase current value; obtaining the sum of the current value of phase A in each first three-phase current value, the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and using the sum as the initial three-phase imbalance of the distribution network under the condition of each first three-phase current value.

[0171] In one embodiment, when the processor executes the computer program, the following steps are further implemented: determining the number of initial three-phase imbalance degrees that match the preset range among all initial three-phase imbalance degrees based on the matching result between each initial three-phase imbalance degree and the preset range; obtaining a ratio between the number and a first preset number; if the ratio is greater than a preset threshold, determining that the three-phase balance result is that the three phases are in a balanced state; if the ratio is not greater than the preset threshold, determining that the three-phase balance result is that the three phases are in an unbalanced state.

[0172] In one embodiment, when the processor executes the computer program, the following steps are also implemented: obtaining a second preset number of second three-phase current values, the second preset number of second three-phase current values are obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number; determining the three-phase amplitude within a quarter cycle based on all the second three-phase current values; the three-phase amplitude includes the current amplitude of phase A, the current amplitude of phase B and the current amplitude of phase C; obtaining the three-phase imbalance of the distribution network based on the three-phase amplitude; and performing three-phase imbalance adjustment on the distribution network based on the three-phase imbalance.

[0173] In one embodiment, when the processor executes the computer program, the following steps are also implemented: obtaining the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value; determining the effective value of the current of phase A within a quarter cycle based on the square of the current value of phase A in all second three-phase current values and a second preset number; determining the current amplitude of phase A within a quarter cycle based on the effective value of the current of phase A; determining the effective value of the current of phase B within a quarter cycle based on the square of the current value of phase B in all second three-phase current values and a second preset number; determining the current amplitude of phase B within a quarter cycle based on the effective value of the current of phase B; determining the effective value of the current of phase C within a quarter cycle based on the square of the current value of phase C in all second three-phase current values and a second preset number; determining the current amplitude of phase C within a quarter cycle based on the effective value of the current of phase C.

[0174] In one embodiment, when the processor executes the computer program, the processor further implements the following steps: obtaining an average current amplitude according to the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C in the three-phase amplitudes;

[0175] The three-phase imbalance of the distribution network is determined based on the maximum current amplitude and the average current amplitude among the three-phase amplitudes.

[0176] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented: obtaining a first preset number of first three-phase current values, the first preset number of first three-phase current values being obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; determining the initial three-phase imbalance of the distribution network under each first three-phase current value condition based on the phase relationship between each first three-phase current value and the three phases; the three phases include phase A, phase B and phase C; determining the three-phase balance result of the distribution network within a preset time length based on all the initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes the time period corresponding to half a cycle.

[0177] In one embodiment, each first three-phase current value includes the current value of phase A, the current value of phase B, and the current value of phase C. When the computer program is executed by the processor, the following steps are also implemented: obtaining the first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees to obtain the first product corresponding to each first three-phase current value; obtaining the second product between the current value of phase C in each first three-phase current value and the cosine value of 240 degrees to obtain the second product corresponding to each three-phase current value; obtaining the sum of the current value of phase A in each first three-phase current value, the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and using the sum as the initial three-phase imbalance of the distribution network under the condition of each first three-phase current value.

[0178] In one embodiment, when the computer program is executed by the processor, the following steps are further implemented: based on the matching result between each initial three-phase imbalance degree and the preset range, determining the number of initial three-phase imbalance degrees that match the preset range among all initial three-phase imbalance degrees; obtaining a ratio between the number and a first preset number; if the ratio is greater than a preset threshold, determining that the three-phase balance result is that the three phases are in a balanced state; if the ratio is not greater than the preset threshold, determining that the three-phase balance result is that the three phases are in an unbalanced state.

[0179] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: obtaining a second preset number of second three-phase current values, the second preset number of second three-phase current values are obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number; determining the three-phase amplitude within a quarter cycle based on all the second three-phase current values; the three-phase amplitude includes the current amplitude of phase A, the current amplitude of phase B and the current amplitude of phase C; obtaining the three-phase imbalance of the distribution network based on the three-phase amplitude; and performing three-phase imbalance adjustment on the distribution network based on the three-phase imbalance.

[0180] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: obtaining the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value; determining the effective value of the current of phase A within a quarter cycle based on the square of the current value of phase A in all second three-phase current values and a second preset number; determining the current amplitude of phase A within a quarter cycle based on the effective value of the current of phase A; determining the effective value of the current of phase B within a quarter cycle based on the square of the current value of phase B in all second three-phase current values and a second preset number; determining the current amplitude of phase B within a quarter cycle based on the effective value of the current of phase B; determining the effective value of the current of phase C within a quarter cycle based on the square of the current value of phase C in all second three-phase current values and a second preset number; determining the current amplitude of phase C within a quarter cycle based on the effective value of the current of phase C.

[0181] In one embodiment, when the computer program is executed by the processor, the following steps are further implemented: obtaining the average current amplitude based on the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C among the three-phase amplitudes; and determining the three-phase imbalance of the distribution network based on the maximum current amplitude and the average current amplitude among the three-phase amplitudes.

[0182] In one embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the following steps: obtaining a first preset number of first three-phase current values, the first preset number of first three-phase current values being obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; determining an initial three-phase imbalance of the distribution network under each first three-phase current value condition based on a phase relationship between each first three-phase current value and the three phases; the three phases include phase A, phase B, and phase C; determining a three-phase balance result of the distribution network within a preset time length based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time length includes a time period corresponding to half a cycle.

[0183] In one embodiment, each first three-phase current value includes the current value of phase A, the current value of phase B, and the current value of phase C. When the computer program is executed by the processor, the following steps are also implemented: obtaining the first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees to obtain the first product corresponding to each first three-phase current value; obtaining the second product between the current value of phase C in each first three-phase current value and the cosine value of 240 degrees to obtain the second product corresponding to each three-phase current value; obtaining the sum of the current value of phase A in each first three-phase current value, the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and using the sum as the initial three-phase imbalance of the distribution network under the condition of each first three-phase current value.

[0184] In one embodiment, when the computer program is executed by the processor, the following steps are further implemented: based on the matching result between each initial three-phase imbalance degree and the preset range, determining the number of initial three-phase imbalance degrees that match the preset range among all initial three-phase imbalance degrees; obtaining a ratio between the number and a first preset number; if the ratio is greater than a preset threshold, determining that the three-phase balance result is that the three phases are in a balanced state; if the ratio is not greater than the preset threshold, determining that the three-phase balance result is that the three phases are in an unbalanced state.

[0185] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: obtaining a second preset number of second three-phase current values, the second preset number of second three-phase current values are obtained by sampling the current of the distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number; determining the three-phase amplitude within a quarter cycle based on all the second three-phase current values; the three-phase amplitude includes the current amplitude of phase A, the current amplitude of phase B and the current amplitude of phase C; obtaining the three-phase imbalance of the distribution network based on the three-phase amplitude; and performing three-phase imbalance adjustment on the distribution network based on the three-phase imbalance.

[0186] In one embodiment, when the computer program is executed by the processor, the following steps are also implemented: obtaining the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value; determining the effective value of the current of phase A within a quarter cycle based on the square of the current value of phase A in all second three-phase current values and a second preset number; determining the current amplitude of phase A within a quarter cycle based on the effective value of the current of phase A; determining the effective value of the current of phase B within a quarter cycle based on the square of the current value of phase B in all second three-phase current values and a second preset number; determining the current amplitude of phase B within a quarter cycle based on the effective value of the current of phase B; determining the effective value of the current of phase C within a quarter cycle based on the square of the current value of phase C in all second three-phase current values and a second preset number; determining the current amplitude of phase C within a quarter cycle based on the effective value of the current of phase C.

[0187] In one embodiment, when the computer program is executed by the processor, the following steps are further implemented: obtaining the average current amplitude based on the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C among the three-phase amplitudes; and determining the three-phase imbalance of the distribution network based on the maximum current amplitude and the average current amplitude among the three-phase amplitudes.

[0188] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0189] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0190] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A method for rapid detection of three-phase imbalance in a distribution network, characterized in that: The method comprises: Obtaining a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; Determining an initial three-phase imbalance of the power distribution network under each first three-phase current value condition based on each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C; Determining a three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time period includes the time period corresponding to the half cycle; The step of determining a three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances includes: According to the matching result between each initial three-phase unbalance degree and the preset range, determining the number of initial three-phase unbalance degrees that match the preset range among all the initial three-phase unbalance degrees; obtaining a ratio between the quantity and the first preset quantity; If the ratio is greater than a preset threshold, determining that the three-phase balance result is that the three phases are in a balanced state; If the ratio is not greater than a preset threshold, determining that the three-phase balance result is that the three phases are in an unbalanced state; Each first three-phase current value includes a current value of phase A, a current value of phase B, and a current value of phase C. Determining the initial three-phase imbalance of the distribution network under each first three-phase current value condition based on each first three-phase current value and a phase relationship between the three phases includes: Obtaining a first product between the current value of phase B in each first three-phase current value and the cosine value of 120 degrees to obtain a first product corresponding to each first three-phase current value; Obtaining a second product between the current value of phase C in each of the first three-phase current values and the cosine value of 240 degrees, to obtain a second product corresponding to each of the three-phase current values; Obtain the sum of the current value of phase A in each first three-phase current value, the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and use the sum as the initial three-phase imbalance of the distribution network under each first three-phase current value condition.

2. The method according to claim 1, characterized in that After determining that the three-phase balance result is that the three phases are in an unbalanced state, the method further includes: Obtaining a second preset number of second three-phase current values, where the second preset number of second three-phase current values are obtained by sampling the current of the power distribution network within a quarter cycle based on a second preset sampling frequency, and the second preset number is less than the first preset number; Determining the three-phase amplitudes within the quarter cycle based on all second three-phase current values; the three-phase amplitudes include the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C; Obtaining a three-phase imbalance degree of the distribution network according to the three-phase amplitudes; The three-phase imbalance is adjusted on the power distribution network according to the three-phase imbalance degree.

3. The method according to claim 2, characterized in that The determining of the three-phase amplitudes within the quarter cycle based on all second three-phase current values includes: Obtaining the square of the current value of phase A, the square of the current value of phase B, and the square of the current value of phase C in each second three-phase current value; determining an effective current value of phase A within the quarter cycle based on the square of the current value of phase A among all the second three-phase current values and the second preset number; determining the current amplitude of phase A within the quarter cycle according to the effective value of the current of phase A; determining an effective current value of phase B within the quarter cycle based on the square of the current value of phase B among all the second three-phase current values and the second preset number; determining the current amplitude of the phase B within the quarter cycle according to the effective value of the current of the phase B; determining an effective current value of phase C within the quarter cycle based on the square of the current value of phase C among all the second three-phase current values and the second preset number; The current amplitude of the C phase within the quarter cycle is determined according to the effective value of the current of the C phase.

4. The method according to claim 2, characterized in that Obtaining the three-phase imbalance of the distribution network according to the three-phase amplitudes includes: Obtaining an average current amplitude based on the current amplitude of phase A, the current amplitude of phase B, and the current amplitude of phase C in the three-phase amplitudes; The three-phase imbalance degree of the power distribution network is determined according to the maximum current amplitude among the three-phase amplitudes and the average current amplitude.

5. A rapid detection device for three-phase imbalance in a distribution network, characterized in that: The device comprises: an acquisition module, configured to acquire a first preset number of first three-phase current values, where the first preset number of first three-phase current values are obtained by sampling the current of the distribution network within half a cycle based on a first preset sampling frequency; A first determining module is configured to determine an initial three-phase imbalance of the power distribution network under each first three-phase current value condition based on each first three-phase current value and a phase relationship between the three phases; the three phases include phase A, phase B, and phase C; A second determining module is configured to determine a three-phase balance result of the distribution network within a preset time period based on all initial three-phase imbalances; the three-phase balance result is that the three phases are in a balanced state or the three phases are in an unbalanced state, and the time period corresponding to the preset time period includes the time period corresponding to the half cycle; The second determination module includes: a first determining unit, configured to determine, based on a matching result between each initial three-phase unbalance degree and a preset range, the number of initial three-phase unbalance degrees that match the preset range among all the initial three-phase unbalance degrees; a fourth obtaining unit, configured to obtain a ratio between the quantity and the first preset quantity; a second determining unit, configured to determine that the three-phase balance result is that the three phases are in a balanced state if the ratio is greater than a preset threshold; a third determining unit, configured to determine that the three-phase balance result is that the three phases are in an unbalanced state if the ratio is not greater than a preset threshold; Each first three-phase current value includes a current value of phase A, a current value of phase B, and a current value of phase C. The first determining module includes: a first acquiring unit, configured to acquire a first product between the current value of phase B in each first three-phase current value and a cosine value of 120 degrees, to obtain a first product corresponding to each first three-phase current value; a second acquiring unit, configured to acquire a second product between the current value of phase C in each of the first three-phase current values and the cosine value of 240 degrees, to obtain a second product corresponding to each of the three-phase current values; The third acquisition unit is used to obtain the current value of phase A in each first three-phase current value, the sum of the first product corresponding to each first three-phase current value, and the second product corresponding to each first three-phase current value, and use the sum as the initial three-phase imbalance of the distribution network under each first three-phase current value condition.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

8. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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