Method and device for determining current abnormality of smart electric energy meter and computer equipment

Abstract

This application discloses a method, apparatus, and computer equipment for determining current anomalies in smart energy meters, relating to the field of energy metering technology. It solves the current problem of being unable to directly locate current faults in smart energy meters, resulting in low fault handling efficiency. The method includes: determining a voltage phasor diagram based on the positive phase sequence of the smart energy meter's voltage; determining the current phasor of the first element based on the voltage of the first element in the voltage phasor diagram, and determining the current phasor of the second element based on the voltage of the second element; calculating the b-phase secondary current of the smart energy meter; and calculating the B-phase primary current on the low-voltage side of the transformer using the b-phase secondary current. The relative error between the B-phase primary current and the B-phase standard current is calculated. If the absolute value of the relative error exceeds a target threshold, a current anomaly is determined in the smart energy meter.

Description

Technical Field

[0001] This application belongs to the field of electricity metering technology, and more specifically, relates to a method, device, computer equipment, and readable storage medium for determining current anomalies in smart electricity meters. Background Technology

[0002] The new type of smart energy meter is a fully electronic energy meter with functions such as energy metering, real-time monitoring, automatic control, information interaction and data processing. As a type of smart meter, the three-phase three-wire smart energy meter is widely used by 10kV high-voltage power supply and metering special transformer users.

[0003] For a three-phase power system, the instantaneous value of each line voltage and the sum of its two line voltages is zero. At this time, the symmetrical three-phase currents caused by the symmetrical three-phase load satisfy the condition that the phasor sum of each phase current and the currents of the other two phases is zero. However, the applicant recognizes that a zero sum of instantaneous values ​​or phasor sums does not necessarily reflect the load balance. When power maintenance personnel inspect smart meters, they often find a significant imbalance between the currents in phases A and C. Based on this phenomenon, it is impossible to directly locate the fault in the smart meter, resulting in low fault handling efficiency. Summary of the Invention

[0004] In view of this, the present invention provides a method, device, computer equipment and readable storage medium for determining current anomalies in smart meters, the main purpose of which is to solve the problem that it is currently impossible to directly locate faults in smart meters and the fault handling efficiency is low.

[0005] According to a first aspect of this application, a method for determining an abnormal current in a smart energy meter is provided. The smart energy meter includes a first element and a second element, and the smart energy meter has phase a, phase b, and phase c. The primary load terminal of the smart energy meter is connected to a transformer including phase B.

[0006] A voltage phasor diagram is determined based on the positive phase sequence of the smart energy meter voltage, wherein, in the voltage phasor diagram, the voltage of the first element... Leading the voltage of the second element The angle is 300°;

[0007] In the voltage phasor diagram, the voltage of the first element is... Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element.

[0008] Based on the current phasor of the first element and the current phasor of the second element Calculate the secondary current of phase b of the smart energy meter by using the fact that the sum of the current phasors of phase a, phase b, and phase c is zero. And utilizing the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer.

[0009] Obtain the standard B-phase current on the low-voltage side of the transformer. Calculate the primary current of phase B. With the B-phase standard current The relative error is such that if the absolute value of the relative error exceeds the target threshold, then the smart energy meter is determined to have an abnormal current.

[0010] Optionally, the voltage of the first element Based on this, determine the current phasor of the first element. include:

[0011] Obtain the active power direction, reactive power direction, and power factor value of the first element;

[0012] Based on the power factor value of the first element, the angle of the first element is calculated using Formula 1. Wherein, the first element angle For the With the The included angle between them, as stated in Formula 1, is:

[0013]

[0014] Where x1 is the power factor value of the first element;

[0015] With the voltage of the first element Based on the active power direction, reactive power direction and the angle of the first element, the following criteria are used: The current direction of the first element is determined in the voltage phasor diagram;

[0016] Read the current value of the first element, and based on the current value and current direction of the first element, obtain the current phasor of the first element.

[0017] Optionally, the step of determining the active power direction, reactive power direction, and angle of the first element is based on the first element. Determining the current direction of the first element in the voltage phasor diagram includes:

[0018] If the active power P of the first element a >0, and the reactive power Q of the first element aIf >0, then confirm. And the first element angle Within the range of 0° to 90°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0019] If the active power P of the first element a <0, and the reactive power Q of the first element a If >0, then confirm. And the first element angle Within the range of 90° to 180°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0020] If the active power P of the first element a <0, and the reactive power Q of the first element a If <0, then determine And the first element angle Within the range of 180° to 270°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x1)], and based on the... As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0021] If the active power P of the first element a >0, and the reactive power Q of the first element a If <0, then determine And the first element angle Within the range of 270° to 360°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x1)], and based on the... As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram.

[0022] Optionally, the voltage of the second element Based on this, determine the current phasor of the second element. include:

[0023] Obtain the active power direction, reactive power direction, and power factor value of the second element;

[0024] Based on the power factor value of the second element, the angle of the second element is calculated using Formula 2. Wherein, the second element angle For the With the The included angle between them, as stated in Formula 2:

[0025]

[0026] Where x2 is the power factor value of the second element;

[0027] With the voltage of the second element Based on the active power direction, reactive power direction, and angle of the second element, the following conditions are considered: The current direction of the second element is determined in the voltage phasor diagram;

[0028] Read the current value of the second element, and based on the current value and current direction of the second element, obtain the current phasor of the second element.

[0029] Optionally, the step of determining the active power direction, reactive power direction, and angle of the second element... Determining the current direction of the second element in the voltage phasor diagram includes:

[0030] If the active power P of the second element c >0, and the reactive power Q of the second element c If >0, then confirm. And the second element angle Within the range of 0° to 90°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram;

[0031] If the active power P of the second element c <0, and the reactive power Q of the second element c If >0, then confirm. And the second element angle Within the range of 90° to 180°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram;

[0032] If the active power P of the second element c <0, and the reactive power Q of the second element c If <0, then determine And the second element angle Within the range of 180° to 270°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x2)], and based on the... As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram;

[0033] If the active power P of the second element c >0, and the reactive power Q of the second element c If <0, then determine And the second element angle Within the range of 270° to 360°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x2)], and based on the... As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram.

[0034] Optionally, the use of the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer. include:

[0035] The transformer's transformation formula is obtained, and the transformation formula is:

[0036]

[0037] Among them, K TA K represents the current transformer ratio, where K is the transformer ratio.

[0038] Based on the b-phase secondary current The primary current of phase B on the low-voltage side of the transformer is calculated using formula 3.

[0039] Optionally, the method further includes:

[0040] If the absolute value of the relative error is greater than 0 and less than the target threshold, then the electricity meter is determined to have an asymmetrical load.

[0041] According to a second aspect of this application, a device for determining abnormal current in a smart energy meter is provided, comprising:

[0042] The first determining module is used to determine a voltage phasor diagram based on the positive phase sequence of the smart energy meter voltage, wherein, in the voltage phasor diagram, the voltage of the first element... Leading the voltage of the second element The angle is 300°;

[0043] The second determining module is configured to, in the voltage phasor diagram, use the voltage of the first element... Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element.

[0044] Calculation module, used for calculation based on the current phasor of the first element and the current phasor of the second element Calculate the secondary current of phase b of the smart energy meter by using the fact that the sum of the current phasors of phases a, b, and c is zero. And utilizing the b-phase secondary current Calculate the primary current of phase B on the low-voltage side of the transformer.

[0045] The third determining module is used to obtain the B-phase standard current on the low-voltage side of the transformer. Calculate the primary current of phase B. With the B-phase standard current The relative error is such that if the absolute value of the relative error exceeds the target threshold, then the current of the electricity meter is determined to be abnormal.

[0046] According to a third aspect of this application, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in any of the first aspects above.

[0047] According to a fourth aspect of this application, a readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any one of the first aspects above.

[0048] By employing the above technical solutions, this application provides a method, apparatus, computer equipment, and readable storage medium for determining abnormal current in a smart energy meter. This application uses the voltage of a first element... Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element. Based on the fact that the sum of the phasors of the three-phase currents a, b, and c is zero, the secondary current of phase b can be obtained. The secondary current of phase b Phase B primary current converted to the low-voltage side of the transformer Calculate the primary current of phase B. Compared with the standard current of phase B The relative error is determined to see if it exceeds the target threshold. If it does, it can be determined that the smart meter has an abnormal current, thus locating the fault type of the smart meter without the need for further fault investigation and analysis, effectively improving fault handling efficiency.

[0049] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0050] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0051] Figure 1 A flowchart of a method for determining current anomalies in a smart energy meter according to an embodiment of this application is shown;

[0052] Figure 2 The diagram illustrates the connection relationship between the ammeter and the transformer in a method for determining current anomalies in a smart energy meter according to an embodiment of this application.

[0053] Figure 3 The voltage phasor diagram of a method for determining current anomalies in a smart energy meter according to an embodiment of this application is shown.

[0054] Figure 4 A schematic diagram of the structure of a device for determining abnormal current in a smart energy meter provided in an embodiment of this application is shown.

[0055] Figure 5 A schematic diagram of the device structure of a computer device provided in an embodiment of this application is shown. Detailed Implementation

[0056] Various embodiments and features of this application are described herein with reference to the accompanying drawings.

[0057] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this application will be apparent to those skilled in the art.

[0058] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0059] These and other features of this application will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0060] It should also be understood that although this application has been described with reference to some specific examples, those skilled in the art can certainly implement many other equivalent forms of this application.

[0061] The above and other aspects, features and advantages of this application will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0062] Specific embodiments of this application are described thereafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of this application, which can be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure the application. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely serve as the basis and representative basis for the claims to teach those skilled in the art to use this application in a variety of substantially any suitable detailed structures.

[0063] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in other embodiments,” all of which may refer to one or more of the same or different embodiments according to this application.

[0064] This application provides a method for determining abnormal current in a smart energy meter. The smart energy meter includes a first element and a second element, and has phases a, b, and c. The primary load terminal of the smart energy meter is connected to a transformer including phase B. Figure 1 As shown, it includes:

[0065] 101. Determine the voltage phasor diagram based on the positive phase sequence of the smart energy meter.

[0066] In this embodiment, it is first necessary to determine that the voltage of the smart energy meter is in positive phase sequence. The voltage phasor diagram is then determined based on the positive phase sequence. Voltage phasor diagrams are a widely used technique for handling smart energy meter problems. In the voltage phasor diagram, the three phases must be 120 degrees apart, and in a clockwise direction (positive phase sequence), they are phase a, phase b, and phase c, indicating that phase a leads phase b, and phase b leads phase c. Once the three-phase voltage phasors are determined, the line voltage, phase current, line current, etc., all have fixed positions. In this embodiment, the voltage of the first element is set. Leading the voltage of the second element The angle is 300°. In actual application, the lead angle can fluctuate by 1° to 2° around 300°. In this embodiment, the smart energy meter measures the voltage between 90% and 115% of the rated voltage, and the smart energy meter measures the current at 1% or more of the rated current.

[0067] Furthermore, the smart energy meter includes two components, namely the first component and the second component. These two components refer to two identical measurement circuits within the smart energy meter, i.e., two current transformers, and the smart energy meter has phase a, phase b, and phase c. It should be noted that, in the embodiments of this application, the wiring principle of the two components of the smart energy meter is to connect one end of each phase power supply or load to a single point, while their other ends serve as leads, which are the three phase lines of the three-phase electricity.

[0068] Furthermore, such as Figure 2 As shown, the primary load terminal of the smart energy meter is connected to the transformer. The side of the transformer connected to the user is the 0.4kV low-voltage side, which also has three phases, namely phase A, phase B and phase C. In this embodiment, only phase B is used, and the other two phases are not specifically described.

[0069] 102. In a voltage phasor diagram, taking the voltage of the first element as an example... Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element.

[0070] 103. Current phasor based on the first element Current phasor of the second element Calculate the secondary current of phase b of the smart energy meter by using the fact that the sum of the current phasors of phases a, b, and c is zero. And utilizing the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer.

[0071] 104. Obtain the standard B-phase current on the low-voltage side of the transformer. Calculate the primary current of phase B. Compared with the standard current of phase B The relative error is determined. If the absolute value of the relative error exceeds the target threshold, then the smart energy meter is determined to have an abnormal current.

[0072] In this embodiment of the application, if the absolute value of the relative error exceeds the target threshold, it can be determined that the smart energy meter has an abnormal current. In practical applications, the main causes of abnormal current are undercurrent theft and current loss fault. For undercurrent theft, illegal electricity theft users can be dealt with in accordance with relevant regulations, and the stolen electricity amount, the electricity fee recovery, and the electricity fee for breach of contract can be calculated. For current loss fault, since the current loss fault is caused by the failure of the metering equipment in operation, it is necessary to calculate the refundable electricity amount and the refundable electricity fee.

[0073] The method provided in this application embodiment uses the voltage of a first element. Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element. Based on the fact that the sum of the phasors of the three-phase currents a, b, and c is zero, the secondary current of phase b can be obtained. The secondary current of phase b Phase B primary current converted to the low-voltage side of the transformer Calculate the primary current of phase B. Compared with the standard current of phase B The relative error is determined to see if it exceeds the target threshold. If it does, it can be determined that the smart meter has an abnormal current, thus locating the fault type of the smart meter without the need for further fault investigation and analysis, effectively improving fault handling efficiency.

[0074] Furthermore, as a refinement and extension of the specific implementation of the above embodiments, in order to fully illustrate the specific implementation process of this embodiment, this application provides another method for determining abnormal current in a smart energy meter. The smart energy meter includes a first element and a second element, and the smart energy meter has phase a, phase b, and phase c. The primary load terminal of the smart energy meter is connected to a transformer including phase B, including:

[0075] 201. Determine the voltage phasor diagram based on the positive phase sequence of the smart energy meter, wherein, in the voltage phasor diagram, the voltage of the first element... Leading the voltage of the second element The angle is 300°.

[0076] 202. In the voltage phasor diagram, take the voltage of the first element as an example. Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element.

[0077] In this embodiment, the active power direction, reactive power direction, power factor value, and current value of the first element are read from the data displayed by the smart energy meter. Based on the power factor value of the first element, the angle of the first element is calculated using Formula 1. Among them, the first element angle for and The included angle between them, as shown in Formula 1, is:

[0078]

[0079] Where x1 is the power factor value of the first element;

[0080] Next, using the voltage of the first element Based on the active power direction, reactive power direction, and angle of the first element, the following criteria are applied. Determine the current direction of the first element in the voltage phasor diagram;

[0081] Subsequently, based on the current value and direction of the first element, the current phasor of the first element is obtained.

[0082] It should be noted that since the active power direction and reactive power direction of the first element both have positive and negative values, the active power direction and reactive power direction of the first element and the angle of the first element are used as the basis for this. There are four ways to determine the current direction of the first element in a voltage phasor diagram, namely:

[0083] If the active power P of the first element a>0, and the reactive power Q of the first element a If >0, then confirm. And the first element angle Within the range of 0° to 90°, and according to the angle of the first element The range of intervals, determine Advanced The angle is And based on Advanced The angle determines the current direction of the first element in the voltage phasor diagram;

[0084] If the active power P of the first element a <0, and the reactive power Q of the first element a If >0, then confirm. And the first element angle Within the range of 90° to 180°, and according to the angle of the first element The range of intervals, determine Advanced The angle is And based on Advanced The angle determines the current direction of the first element in the voltage phasor diagram;

[0085] If the active power P of the first element a <0, and the reactive power Q of the first element a If <0, then determine And the first element angle Within the range of 180° to 270°, and according to the angle of the first element The range of intervals, determine Advanced The angle is 360° + [-arccos(x1)], and based on As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0086] If the active power P of the first element a >0, and the reactive power Q of the first element a If <0, then determine And the first element angle Within the range of 270° to 360°, and according to the angle of the first element The range of intervals, determine Advanced The angle is 360° + [-arccos(x1)], and based on Advanced The angle determines the current direction of the first element in the voltage phasor diagram.

[0087] In this embodiment, the active power direction, reactive power direction, power factor, and current value of the second element are read from the data displayed by the smart energy meter. Based on the power factor of the second element, the angle of the second element is calculated using Formula 2. Among them, the second element angle for and The included angle between them, Formula 2 is:

[0088]

[0089] Where x2 is the power factor of the second element;

[0090] Next, using the voltage of the second element Based on the active power direction, reactive power direction, and angle of the second element, the following criteria are used: Determine the current direction of the second element in the voltage phasor diagram;

[0091] Subsequently, based on the current value and direction of the second element, the current phasor of the second element is obtained.

[0092] It should be noted that, since the active power direction and reactive power direction of the second element both have positive and negative values, the active power direction and reactive power direction of the second element, and the angle of the second element, are used to determine the direction of the active power direction and reactive power direction. There are four ways to determine the current direction of the first element in a voltage phasor diagram, namely:

[0093] If the active power P of the second element c >0, and the reactive power Q of the second element c If >0, then confirm. And the second element angle Within the range of 0° to 90°, and according to the second element angle The range of intervals, determine Advanced The angle is And based on Advanced The angle determines the current direction of the second element in the voltage phasor diagram;

[0094] If the active power P of the second element c <0, and the reactive power Q of the second element c If >0, then confirm. And the second element angle Within the range of 90° to 180°, and according to the second element angle The range of intervals, determine Advanced The angle is And based on Advanced The angle determines the current direction of the second element in the voltage phasor diagram;

[0095] If the active power P of the second element c <0, and the reactive power Q of the second element c If <0, then determine And the second element angle Within the range of 180° to 270°, and according to the second element angle The range of intervals, determine Advanced The angle is 360° + [-arccos(x2)], and based on Advanced The angle determines the current direction of the second element in the voltage phasor diagram;

[0096] If the active power P of the second element c >0, and the reactive power Q of the second element c If <0, then determine And the second element angle Within the range of 270° to 360°, and according to the second element angle The range of intervals, determine Advanced The angle is 360° + [-arccos(x2)], and based on Advanced The angle determines the current direction of the second element in the voltage phasor diagram.

[0097] 203. Current phasor based on the first element Current phasor of the second element Calculate the secondary current of phase b of the smart energy meter by using the fact that the sum of the current phasors of phases a, b, and c is zero. And utilizing the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer.

[0098] In this embodiment of the application, since the 10kV side of the 10kV high-voltage power supply and metering dedicated transformer for users belongs to a neutral point ungrounded system, the three-phase current phasors and Therefore, the current phasor of the first element is known. Current phasor of the second element The phase b secondary current of the smart energy meter can be obtained through calculation.

[0099] Furthermore, utilizing the b-phase secondary current of the smart meter Calculate the primary current of phase B on the low-voltage side of the transformer. The specific steps include:

[0100] First, obtain the transformer's transformation formula, which is:

[0101]

[0102] Among them, K TA K represents the current transformer ratio, where K is the transformer ratio.

[0103] Subsequently, based on the b-phase secondary current Calculate the B-phase primary current on the low-voltage side of the transformer using Formula 3.

[0104] 204. Obtain the standard B-phase current on the low-voltage side of the transformer. Calculate the primary current of phase B. Compared with the standard current of phase B The relative error is determined. If the absolute value of the relative error exceeds the target threshold, then the smart energy meter is determined to have an abnormal current.

[0105] In this embodiment, a clamp meter is used to measure the standard value of the primary current of phase B on the 0.4kV low-voltage side of the transformer, i.e., the standard current of phase B. Calculated value of primary current of phase B on the 0.4kV side of the transformer Compared with standard value Compare and calculate the relative error, as shown in Formula 4.

[0106]

[0107] Setting a target threshold is related to factors such as the synchronicity of system data and the degree of current distribution in practical applications. In actual work, the target threshold needs to be adjusted appropriately according to the accuracy of the mathematical model to ensure the accuracy of the mathematical model's judgment. In this embodiment, the target threshold can be set to 5%. If the absolute value of the relative error exceeds 5%, it can be determined that the smart meter has an abnormal current, which can be judged as "undercurrent theft or current loss fault". If the absolute value of the relative error is greater than 0 and less than 5%, it can be determined that the smart meter has an unbalanced load. The unbalanced load is only due to the unbalanced load connected to the low-voltage side of the user transformer. The three-phase three-wire smart meter with high supply and high metering is measuring correctly, and there is no need to refund or supplement the electricity consumption and electricity fees.

[0108] Specific embodiments of the above technical solution are shown below:

[0109] For example, a 10kV dedicated transformer user uses three-phase three-wire metering on the 10kV side, with a TV ratio of 10 / 0.1kV, a TA ratio of 75 / 5A, and a transformer ratio of 10 / 0.4kV (ratio of 25). The primary current of phase B measured on the 0.4kV low-voltage side is 566A. The smart energy meter is in positive phase sequence, and the load power factor angle is approximately 15° (inductive). The displayed data is: U ab =102.8V, U cb =102.1V, I a =1.51A, I c =0.11A, P a =109.77W, P c =5.77W, Q a =109.77Var,Q c = -9.63Var,

[0110] Specifically, due to Pa=109.77W, Qa=109.77Var, Advanced The angle is 45°, combined with the current value I of the first element. a =1.51A, such as Figure 3 As shown, in the voltage phasor diagram, the current phasor of the first element can be determined.

[0111] Furthermore, due to Pc = 5.77W, Qc = -9.63Var Sure Advanced The angle is 360° - 59° = 301°, combined with the current value I of the second element. c =0.11A, such as Figure 3 As shown, the current phasor of the second element can be determined in the voltage phasor diagram.

[0112] From the formula I was calculated b =1.30A, continue to use the formula to calculate the primary current value of phase B on the 0.4kV low-voltage side of the transformer. Right now, Calculated value of primary current of phase B on the 0.4kV low-voltage side of the transformer Comparison with standard values Calculate the relative error, that is,

[0113]

[0114] As can be seen from the above formula, a relative error of 13.8% is greater than the threshold of 5%, which indicates a power theft due to insufficient current or a power loss fault.

[0115] The method provided in this application embodiment uses the voltage of a first element. Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element. Based on the fact that the sum of the phasors of the three-phase currents a, b, and c is zero, the secondary current of phase b can be obtained. The secondary current of phase b Phase B primary current converted to the low-voltage side of the transformer Calculate the primary current of phase B. Compared with the standard current of phase B The relative error is determined to see if it exceeds the target threshold. If it does, it can be determined that the current of the electricity meter is abnormal. If it is less than the target threshold, it can be determined that the electricity meter has an unbalanced load. This allows the type of fault in the ammeter to be located without further troubleshooting and analysis, thus effectively improving the efficiency of fault handling.

[0116] Furthermore, as Figure 1 The specific implementation of the method is as follows: Figure 4 As shown in the figure, this application provides a device for determining abnormal current in a smart energy meter, including: a first determining module 401, a second determining module 402, a calculation module 403, and a third determining module 404.

[0117] The first determining module 401 is used to determine a voltage phasor diagram based on the positive phase sequence of the smart energy meter voltage, wherein, in the voltage phasor diagram, the voltage of the first element... Leading the voltage of the second element The angle is 300°;

[0118] The second determining module 402 is used in the voltage phasor diagram to determine the voltage of the first element. Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element.

[0119] The calculation module 403 is used to calculate based on the current phasor of the first element. and the current phasor of the second element Calculate the secondary current of phase b of the energy meter by using the fact that the sum of the current phasors of phases a, b, and c is zero. And utilizing the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer.

[0120] The third determining module 404 is used to obtain the B-phase standard current on the low-voltage side of the transformer. Calculate the primary current of phase B. With the B-phase standard current The relative error is such that if the absolute value of the relative error exceeds the target threshold, then the smart energy meter is determined to have an abnormal current.

[0121] In specific application scenarios, the second determining module 302 is also used for:

[0122] Obtain the active power direction, reactive power direction, and power factor value of the first element;

[0123] Based on the power factor value of the first element, the angle of the first element is calculated using Formula 1. Wherein, the first element angle For the With the The included angle between them, as stated in Formula 1, is:

[0124]

[0125] Where x1 is the power factor value of the first element;

[0126] With the voltage of the first element Based on the active power direction, reactive power direction and the angle of the first element, the following criteria are used: The current direction of the first element is determined in the voltage phasor diagram;

[0127] Read the current value of the first element, and based on the current value and current direction of the first element, obtain the current phasor of the first element.

[0128] In specific application scenarios, the second determining module 402 is also used for:

[0129] If the active power P of the first element a >0, and the reactive power Q of the first element a If >0, then confirm. And the first element angle Within the range of 0° to 90°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0130] If the active power P of the first element a <0, and the reactive power Q of the first element a If >0, then confirm. And the first element angle Within the range of 90° to 180°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0131] If the active power P of the first element a <0, and the reactive power Q of the first element a If <0, then determine And the first element angle Within the range of 180° to 270°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x1)], and based on the... As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram;

[0132] If the active power P of the first element a >0, and the reactive power Q of the first element a If <0, then determine And the first element angle Within the range of 270° to 360°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x1)], and based on the... As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram.

[0133] In specific application scenarios, the second determining module 402 is also used for:

[0134] Obtain the active power direction, reactive power direction, and power factor value of the second element;

[0135] Based on the power factor value of the second element, the angle of the second element is calculated using Formula 2. Wherein, the second element angle For the With the The included angle between them, as stated in Formula 2:

[0136]

[0137] Where x2 is the power factor value of the second element;

[0138] With the voltage of the second element Based on the active power direction, reactive power direction, and angle of the second element, the following conditions are considered: The current direction of the second element is determined in the voltage phasor diagram;

[0139] Read the current value of the second element, and based on the current value and current direction of the second element, obtain the current phasor of the second element.

[0140] In specific application scenarios, the second determining module 402 is also used for:

[0141] If the active power P of the second element c >0, and the reactive power Q of the second element c If >0, then confirm. And the second element angle Within the range of 0° to 90°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram;

[0142] If the active power P of the second element c <0, and the reactive power Q of the second element c If >0, then confirm. And the second element angle Within the range of 90° to 180°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is And based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram;

[0143] If the active power P of the second element c <0, and the reactive power Q of the second element c If <0, then determine And the second element angle Within the range of 180° to 270°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x2)], and based on the... As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram;

[0144] If the active power P of the second element c >0, and the reactive power Q of the second element c If <0, then determine And the second element angle Within the range of 270° to 360°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is 360° + [-arccos(x2)], and based on the... As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram.

[0145] In specific application scenarios, this computing module 403 is also used for:

[0146] The transformer's transformation formula is obtained, and the transformation formula is:

[0147]

[0148] Among them, K TA K represents the current transformer ratio, where K is the transformer ratio.

[0149] Based on the b-phase secondary current The primary current of phase B on the low-voltage side of the transformer is calculated using formula 3.

[0150] In specific application scenarios, the third determining module 404 is also used for:

[0151] If the absolute value of the relative error is greater than 0 and less than the target threshold, then the electricity meter is determined to have an asymmetrical load.

[0152] The apparatus provided in this application embodiment uses a second determining module to determine the voltage of a first element. Based on this, determine the current phasor of the first element. and the voltage of the second element Based on this, determine the current phasor of the second element. The calculation module calculates the secondary current of phase b based on the fact that the sum of the phasors of the three-phase currents (a, b, and c) is zero. The secondary current of phase b Phase B primary current converted to the low-voltage side of the transformer The primary current of phase B is calculated using the third determination module. Compared with the standard current of phase B The relative error is determined to see if it exceeds the target threshold. If it does, it can be determined that the smart meter has an abnormal current, thus locating the type of fault in the meter without the need for further troubleshooting and analysis, effectively improving the efficiency of fault handling.

[0153] In an exemplary embodiment, see Figure 5 The invention also provides a computer device including a bus, a processor, a memory, and a communication interface. It may also include an input / output interface and a display device, wherein the various functional units can communicate with each other via the bus. The memory stores a computer program, and the processor executes the program stored in the memory to perform the method for determining abnormal current in a smart energy meter as described in the above embodiments.

[0154] A readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for determining current anomalies in a smart energy meter.

[0155] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented in hardware or by using software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) and includes several instructions to cause a computer device (such as a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0156] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing this application.

[0157] Those skilled in the art will understand that the modules in the apparatus of the implementation scenario can be distributed within the apparatus of the implementation scenario as described, or they can be located in one or more apparatuses different from this implementation scenario, with corresponding changes. The modules of the above-described implementation scenario can be combined into one module, or they can be further divided into multiple sub-modules.

[0158] The serial numbers in this application are for descriptive purposes only and do not represent the superiority or inferiority of the implementation scenario.

[0159] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. A method for determining abnormal current in a smart energy meter, wherein the smart energy meter includes a first element and a second element, and the smart energy meter has phase a, phase b, and phase c, and the primary load terminal of the smart energy meter is connected to a transformer including phase B, characterized in that, include: A voltage phasor diagram is determined based on the positive phase sequence of the smart energy meter voltage, wherein, in the voltage phasor diagram, the voltage of the first element... Leading the voltage of the second element The angle is 300°; In the voltage phasor diagram, the voltage of the first element is... Based on this, determine the current phasor of the first element. and with the voltage of the second element Based on this, determine the current phasor of the second element. ; Based on the current phasor of the first element and the current phasor of the second element The secondary current of phase b of the smart energy meter is calculated by using the fact that the sum of the current phasors of phase a, phase b, and phase c is zero. And utilizing the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer. ; Obtain the standard B-phase current on the low-voltage side of the transformer. Calculate the primary current of phase B. With the B-phase standard current The relative error is such that if the absolute value of the relative error exceeds the target threshold, then the smart energy meter is determined to have an abnormal current.

2. The method of claim 1, wherein the current anomaly is determined by: determining the first element current phasor as a reference, determining the first element current phasor comprising: Obtain the active power direction, reactive power direction, and power factor value of the first element; Based on the power factor value of the first element, the angle of the first element is calculated using Formula 1. Wherein, the first element angle For the With the The included angle between them, as stated in Formula 1, is: ， （1） Where x1 is the power factor value of the first element; With the voltage of the first element Based on the active power direction, reactive power direction and the angle of the first element, the following criteria are used: The current direction of the first element is determined in the voltage phasor diagram; Read the current value of the first element, and based on the current value and current direction of the first element, obtain the current phasor of the first element. .

3. The method of claim 2, wherein the current anomaly is determined based on the current value and the current threshold value. said first element angle determining a current direction of the first element in the voltage phasor diagram, comprises If the active power of the first element And the reactive power of the first element Then determine And the first element angle Within the range of 0° to 90°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is and based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram; If the active power of the first element And the reactive power of the first element Then determine And the first element angle Within the range of 90° to 180°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is and based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram; If the active power of the first element And the reactive power of the first element Then determine And the first element angle Within the range of 180° to 270°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is 360°+[ ], and based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram; If the active power of the first element And the reactive power of the first element Then determine And the first element angle Within the range of 270° to 360°, and according to the angle of the first element The interval range is determined by the following. As mentioned earlier The angle is 360°+[ ], and based on the As mentioned earlier The angle determines the current direction of the first element in the voltage phasor diagram.

4. The method of claim 1, wherein the current anomaly is determined based on a comparison of the current value with a threshold value. said second element voltage as a reference, determining a current phasor of said second element comprising: Obtain the active power direction, reactive power direction, and power factor value of the second element; Based on the power factor value of the second element, the angle of the second element is calculated using Formula 2. The second element angle For the With the The included angle between them, as stated in Formula 2: ， （2） Where x2 is the power factor value of the second element; With the voltage of the second element Based on the active power direction, reactive power direction, and angle of the second element, the following conditions are considered: The current direction of the second element is determined in the voltage phasor diagram; Read the current value of the second element, and based on the current value and current direction of the second element, obtain the current phasor of the second element. .

5. The method for determining current anomalies in smart energy meters according to claim 4, characterized in that, The active power direction, reactive power direction, and angle of the second element are determined according to the second element. Determining the current direction of the second element in the voltage phasor diagram includes: If the active power of the second element And the reactive power of the second element Then determine And the second element angle Within the range of 0° to 90°, and according to the second element angle The interval range is determined by the following. As mentioned earlier The angle is and based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram; If the active power of the second element And the reactive power of the second element Then determine And the second element angle Within the range of 90° to 180°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is and based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram; If the active power of the second element And the reactive power of the second element Then determine And the second element angle Within the range of 180° to 270°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is 360°+[ ], and based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram; If the active power of the second element And the reactive power of the second element Then determine And the second element angle Within the range of 270° to 360°, and according to the angle of the second element The interval range is determined by the following. As mentioned earlier The angle is 360°+[ ], and based on the As mentioned earlier The angle determines the current direction of the second element in the voltage phasor diagram.

6. The method for determining abnormal current in a smart energy meter according to claim 1, characterized in that, The method utilizes the b-phase secondary current of the smart energy meter. Calculate the primary current of phase B on the low-voltage side of the transformer. ,include: The transformer's transformation formula is obtained, and the transformation formula is: ， （3） wherein, is the ratio of the current transformer, is the ratio of the transformer; based on the b-phase secondary current the transformer low voltage side B-phase primary current is calculated by equation 3 .

7. The method of claim 1, wherein the current anomaly is determined by the steps of: determining a current anomaly if the current value is greater than the current threshold value. The method further includes: If the absolute value of the relative error is greater than 0 and less than the target threshold, then the electricity meter is determined to have an asymmetrical load.

8. A device for determining abnormal current in a smart energy meter, characterized in that, include: The first determining module is used to determine a voltage phasor diagram based on the positive phase sequence of the smart energy meter voltage, wherein, in the voltage phasor diagram, the voltage of the first element... Leading the voltage of the second element The angle is 300°; The second determining module is configured to, in the voltage phasor diagram, use the voltage of the first element... Based on this, determine the current phasor of the first element. and with the voltage of the second element Based on this, determine the current phasor of the second element. ; Calculation module, used for calculation based on the current phasor of the first element and the current phasor of the second element The secondary current of phase b of the smart energy meter is calculated by using the fact that the sum of the current phasors of phases a, b, and c is zero. And utilizing the b-phase secondary current of the smart energy meter Calculate the primary current of phase B on the low-voltage side of the transformer. ; The third determining module is used to obtain the B-phase standard current on the low-voltage side of the transformer. Calculate the primary current of phase B. With the B-phase standard current The relative error is such that if the absolute value of the relative error exceeds the target threshold, then the smart energy meter is determined to have an abnormal current. 9.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-8 when the computer program is executed by the processor. When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A readable storage medium, having stored thereon a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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