Rapid screening method for false wiring of three-phase four-wire electric energy meter

Abstract

The invention relates to the technical field of metering wiring of a three-phase four-wire electric energy meter, in particular to a method for quickly screening wrong wiring of a three-phase four-wire electric energy meter, which is mainly used for quickly and accurately screening the three-phase four-wire electric energy meter with wrong wiring on the basis of data acquisition of a power consumer electricity utilization information acquisition system. Comprising the following steps: step 1, analyzing voltage and voltage and current phase angle characteristics of a three-phase four-wire electric energy meter, and analyzing a phase angle with normal voltage and a phase angle with normal voltage and current; 2, acquiring the voltage of the three-phase electric energy meter and the phase angle of the voltage and the current in real time through a power consumer electricity utilization information acquisition system; 3, analyzing and screening out users with abnormal voltage and current angles; and 4, exporting a wrong wiring user list, and performing manual on-site verification and rectification.

Description

Technical Field

[0001] The invention relates to the technical field of three-phase four-wire electric energy meter measurement wiring, and in particular to a rapid screening method for incorrect wiring of a three-phase four-wire electric energy meter. Background Art

[0002] With economic development, electricity demand is increasing, and three-phase four-wire energy meters are increasingly used in power grid electricity bill settlement. Therefore, the accuracy of the measurement is determined by whether the wiring of the three-phase four-wire energy meter is correct or not. However, due to the uneven technical level of the installers, negligence during installation leads to wiring errors of the three-phase four-wire energy meter, which brings economic losses to both parties of the power trade.

[0003] At present, users with incorrect wiring can only be discovered through the user electricity consumption information collection system and line loss system. It is difficult to discover users with small electricity consumption and little impact on line loss in time. In addition, this screening method is not accurate and requires manual on-site testing and confirmation with professional instruments. There is a lack of technical means to quickly screen out incorrect wiring of three-phase four-wire electricity meters, improve work efficiency, and reduce workload. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the present invention provides a method for quickly screening incorrectly wired three-phase four-wire electricity meters, which can quickly and accurately screen out incorrectly wired three-phase four-wire electricity meters based on data collection by an electricity consumption information collection system of power users.

[0006] (II) Technical solution

[0007] To achieve the above object, the present invention provides the following technical solution: a method for quickly screening incorrect wiring of a three-phase four-wire electric energy meter, comprising the following steps:

[0008] Step 1: Analyze the voltage and voltage and current phase angle characteristics of the three-phase four-wire electric energy meter, and analyze the normal phase angle of the voltage and the normal phase angle of the voltage and current;

[0009] Step 2: Collect the voltage and phase angle of voltage and current of the three-phase energy meter in real time through the power user power consumption information collection system;

[0010] Step 3: Analyze and filter out users with abnormal voltage and current angles;

[0011] Step 4: Export the list of incorrectly wired users, and manually verify and correct them on site.

[0012] Further, the present invention is improved in that step one specifically comprises the following steps:

[0013] 1a: The angle between the phase voltages of the first and second elements of the three-phase four-wire is defined as ∠U1U2, the angle between the phase voltages of the first and third elements of the three-phase four-wire is defined as ∠U1U3, the angle between the phase voltage and current of the first element of the three-phase four-wire electric energy meter is defined as ∠U1I1, the angle between the phase voltage and current of the second element of the three-phase four-wire electric energy meter is defined as ∠U2I2, and the angle between the phase voltage and current of the third element of the three-phase four-wire electric energy meter is defined as ∠U3I3;

[0014] 1b: According to the characteristics of alternating current, the normal phase angle of the voltage of the three-phase four-wire electric energy meter is: the voltage angle of the positive phase sequence is ∠U1U2=120°, ∠U1U3=240°; the voltage angle of the reverse phase sequence is ∠U1U2=240°, ∠U1U3=120°;

[0015] 1c: It is analyzed that the normal phase angle of the voltage and current of the three-phase four-wire electric energy meter during the forward power flow is: ∠U1I1=270°~90°, ∠U2I2=270°~90°, ∠U3I3=270°~90°; the normal phase angle of the voltage and current of the three-phase four-wire electric energy meter during the reverse power flow is: ∠U1I1=90°~270°, ∠U2I2=90°~270°, ∠U3I3=90°~270°;

[0016] 1d: By the method of elimination, the angles that are not within the normal range are regarded as three-phase four-wire energy meters with incorrect wiring. The voltage angle of the three-phase four-wire energy meter is ∠U1U2≠120° or 240°, and ∠U1U3≠240° or 120°;

[0017] 1e: When the current wiring is abnormal: the phase angle of the voltage and current of the three-phase four-wire electric energy meter during forward power flow is: ∠U1I1=91°~269°, ∠U2I2=91°~269°, ∠U3I3=91°~269°; the phase angle of the voltage and current of the three-phase four-wire electric energy meter during reverse power flow is: ∠U1I1=271°~89°, ∠U2I2=271°~89°, ∠U3I3=271°~89°.

[0018] Further, the present invention is improved in that step three specifically comprises the following steps:

[0019] 3a: Determine whether the wiring is correct by comparing the phase angles of voltage and current;

[0020] 3b: Since wiring errors may be accidental, it is necessary to measure multiple times and compare the results;

[0021] 3c: Use an automated data acquisition system to record angle data under different conditions.

[0022] (III) Beneficial effects

[0023] Compared with the prior art, the present invention provides a method for quickly screening incorrect wiring of three-phase four-wire electricity meters, which has the following beneficial effects: the present invention is suitable for quickly screening incorrect wiring of three-phase four-wire electricity meters, and can quickly screen out incorrectly wired three-phase four-wire electricity meters from a large number of users, correct them in time, and improve the work efficiency of metering management. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a flow chart of a method for quickly screening wrong wiring of a three-phase four-wire electric energy meter according to the present invention;

[0025] Figure 2 It is a phasor diagram of a three-phase four-wire electric energy meter with a correct positive phase sequence connection during a forward power flow or a phasor diagram of a wrong positive phase sequence connection during a reverse power flow;

[0026] Figure 3 It is a phasor diagram of a three-phase four-wire electric energy meter with a correct reverse phase sequence connection during a forward power flow or a phasor diagram of an incorrect reverse phase sequence connection during a reverse power flow;

[0027] Figure 4 It is a phasor diagram of a three-phase four-wire electric energy meter with incorrect connection of a positive phase sequence current line during forward power flow or a phasor diagram of a correct connection of a positive phase sequence current line during reverse power flow;

[0028] Figure 5 The present invention discloses a phasor diagram of a three-phase four-wire electric energy meter with a wrong connection of a reverse phase sequence current line during a forward power flow or a phasor diagram of a correct connection of a reverse phase sequence current line during a reverse power flow. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] See also Figure 1-Figure 5 The present invention is a rapid screening method for incorrect wiring of a three-phase four-wire electric energy meter, comprising the following steps:

[0031] Step 1: Analyze the voltage and voltage and current phase angle characteristics of the three-phase four-wire electric energy meter, and analyze the normal phase angle of the voltage and the normal phase angle of the voltage and current;

[0032] Step 1 specifically includes the following steps:

[0033] 1a: The angle between the phase voltages of the first and second elements of the three-phase four-wire is defined as ∠U1U2, the angle between the phase voltages of the first and third elements of the three-phase four-wire is defined as ∠U1U3, the angle between the phase voltage and current of the first element of the three-phase four-wire electric energy meter is defined as ∠U1I1, the angle between the phase voltage and current of the second element of the three-phase four-wire electric energy meter is defined as ∠U2I2, and the angle between the phase voltage and current of the third element of the three-phase four-wire electric energy meter is defined as ∠U3I3;

[0034] 1b: According to the characteristics of alternating current, the normal phase angle of the voltage of the three-phase four-wire electric energy meter is: the voltage angle of the positive phase sequence is ∠U1U2=120°, ∠U1U3=240°; the voltage angle of the reverse phase sequence is ∠U1U2=240°, ∠U1U3=120°;

[0035] 1c: According to the characteristics of the load, it is generally divided into capacitive load and inductive load. According to the current phase principle, the three-phase four-wire energy meter has a two-way power flow measurement function. It is analyzed that the normal phase angle of the voltage and current of the three-phase four-wire energy meter during the forward power flow is: ∠U1I1=270°~90°, ∠U2I2=270°~90°, ∠U3I3=270°~90°; the normal phase angle of the voltage and current of the three-phase four-wire energy meter during the reverse power flow is: ∠U1I1=90°~270°, ∠U2I2=90°~270°, ∠U3I3=90°~270°;

[0036] 1d: When the voltage wiring is abnormal: Based on the voltage phase angle under the above normal wiring conditions, the angle that is not in the normal range can be regarded as a three-phase four-wire energy meter with incorrect wiring through the elimination method. The voltage angle of the three-phase four-wire energy meter is ∠U1U2≠120° or 240°, and ∠U1U3≠240° or 120°;

[0037] 1e: When the current wiring is abnormal: the phase angle between the voltage and current of the three-phase four-wire electric energy meter during the forward power flow is: ∠U1I1=91°~269°, ∠U2I2=91°~269°, ∠U3I3=91°~269°; the phase angle between the voltage and current of the three-phase four-wire electric energy meter during the reverse power flow is: ∠U1I1=271°~89°, ∠U2I2=271°~89°, ∠U3I3=271°~89°;

[0038] Step 2: Collect the voltage and phase angle of voltage and current of the three-phase energy meter in real time through the power user power consumption information collection system;

[0039] Step 3: Analyze and filter out users with abnormal voltage and current angles;

[0040] Step three specifically includes the following steps:

[0041] 3a: Phase angle deviation detection: Determine whether the wiring is correct by comparing the phase angles of voltage and current;

[0042] 3b: Multiple measurements to confirm: Since wiring errors may be accidental, multiple measurements and comparison of results are required to ensure the accuracy of the conclusion;

[0043] 3c: Data collection and processing: Use an automated data collection system to record angle data under different conditions, and process and analyze it through professional software to improve the efficiency and accuracy of detection;

[0044] Step 4: Export the list of incorrectly wired users, and manually verify and correct them on site.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rapid screening method for incorrect wiring of a three-phase four-wire electric energy meter, characterized in that: The following steps are involved: Step 1: Analyze the voltage and voltage and current phase angle characteristics of the three-phase four-wire electric energy meter, and analyze the normal phase angle of the voltage and the normal phase angle of the voltage and current; Step 2: Collect the voltage and phase angle of voltage and current of the three-phase energy meter in real time through the power user power consumption information collection system; Step 3: Analyze and filter out users with abnormal voltage and current angles; Step 4: Export the list of incorrectly wired users, and manually verify and correct them on site.

2. A rapid screening method for incorrect wiring of a three-phase four-wire electric energy meter according to claim 1, characterized in that: Step 1 specifically includes the following steps: 1a: The angle between the phase voltages of the first and second elements of the three-phase four-wire is defined as ∠U1U2, the angle between the phase voltages of the first and third elements of the three-phase four-wire is defined as ∠U1U3, the angle between the phase voltage and current of the first element of the three-phase four-wire electric energy meter is defined as ∠U1I1, the angle between the phase voltage and current of the second element of the three-phase four-wire electric energy meter is defined as ∠U2I2, and the angle between the phase voltage and current of the third element of the three-phase four-wire electric energy meter is defined as ∠U3I3; 1b: According to the characteristics of alternating current, the normal phase angle of the voltage of the three-phase four-wire electric energy meter is: the voltage angle of the positive phase sequence is ∠U1U2=120°, ∠U1U3=240°; the voltage angle of the reverse phase sequence is ∠U1U2=240°, ∠U1U3=120°; 1c: It is analyzed that the normal phase angle of the voltage and current of the three-phase four-wire electric energy meter during the forward power flow is: ∠U1I1=270°~90°, ∠U2I2=270°~90°, ∠U3I3=270°~90°; the normal phase angle of the voltage and current of the three-phase four-wire electric energy meter during the reverse power flow is: ∠U1I1=90°~270°, ∠U2I2=90°~270°, ∠U3I3=90°~270°; 1d: By the method of elimination, the angles that are not within the normal range are regarded as three-phase four-wire energy meters with incorrect wiring. The voltage angle of the three-phase four-wire energy meter is ∠U1U2≠120° or 240°, and ∠U1U3≠240° or 120°; 1e: When the current wiring is abnormal: the phase angle of the voltage and current of the three-phase four-wire electric energy meter during forward power flow is: ∠U1I1=91°~269°, ∠U2I2=91°~269°, ∠U3I3=91°~269°; the phase angle of the voltage and current of the three-phase four-wire electric energy meter during reverse power flow is: ∠U1I1=271°~89°, ∠U2I2=271°~89°, ∠U3I3=271°~89°.

3. A rapid screening method for incorrect wiring of a three-phase four-wire electric energy meter according to claim 2, characterized in that: Step 3 Specific The following steps are involved: 3a: Determine whether the wiring is correct by comparing the phase angles of voltage and current; 3b: Since wiring errors may be accidental, it is necessary to measure multiple times and compare the results; 3c: Use an automated data acquisition system to record angle data under different conditions.

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