Error Detection Wiring Circuit and Switching Device for Instrument Transformers in Distribution Power Grid

Abstract

The invention discloses an error detection wiring circuit and switching device for instrument transformers in distribution power grid, wherein the wiring circuit integrates a three-phase three-wire metering circuit and a three-phase four-wire metering circuit, and the switching device comprises a linear push rod and a driving motor. Through the control of the driving motor, the movement of the linear push rod to the through terminal ports, which consist of the BN terminal, the CN terminal, and the P1B terminal, is realized. With this, the conversion of the two methods can be realized by simply switching the short circuit wiring of the P1B terminal or the BN terminal to the CN terminal and the AN terminal. Using certain measurement method, each phase of the transformer to be tested can be measured simultaneously, which improves the accuracy of the detected data. Meanwhile, the prior art of wiring conduction structure is changed into a rod-shaped jack-type conduction structure, such that the two-step wiring procedure is reduced to one step during measurement, which can be realized by simply controlling the forward and reverse rotation of the driving motor. No manual wiring operation is required, which is safer and more convenient, and greatly improves the efficiency of wiring conversion during measurement.

Claims

1. An instrument transformer error detection wiring circuit, including a transformer to be tested, and also including A, B, C three-phase standard voltage transformers and A, B, C three-phase boosters, is characterized in that: one end of the said A-phase standard voltage transformer is connected to the P1A terminal, and the other end is connected to the AN terminal; One end of the said B-phase standard voltage transformer is connected to the P1B terminal, and the other end is connected to the BN terminal; One end of the said C-phase standard voltage transformer is connected to the P1B terminal, and the other end is connected to the CN terminal; P1A, P1B, and P1C are the high-voltage-end terminals of the primary side of the A, B, and C-phase of the boosters, respectively, and the AN, BN, and CN are the low-voltage-end terminals of the primary side of the A, B, and C-phase of the boosters, respectively; The said AN terminal is short-circuited with the CN terminal, the BN terminal is grounded, and the P1A, P1B, and P1C terminals are connected to the tested transformer respectively, where: When the P1B terminal is connected to the short wiring of the CN terminal and the AN terminal, and the error detection for the instrument transformer in distribution power grid with three-phase three-wire method is performed using the three-phase detection method; When the BN terminal is connected to the short wiring of the CN terminal and the AN terminal, and the error detection for the instrument transformer in distribution power grid with three-phase four-wire method is performed using the three-phase detection method.

2. According to claim 1, the said transformer error detection wiring circuit, including the transformer to be tested, and also including A, B, C three-phase standard voltage transformers and A, B, C three-phase boosters, is characterized in that: The said input terminal of P1A is also connected to the A-phase booster and phase A of the transformer to be tested, respectively, and its output terminal is connected to phase A of the transformer to be tested through the A-phase current booster and the A-phase standard current transformer in sequence; The said input terminal of P1B is also connected to the B-phase booster and phase B of the transformer to be tested, respectively, and its output terminal is connected to phase B of the transformer to be tested through the B-phase current booster and the B-phase standard current transformer in sequence; The said input terminal of P1C is also connected to the C-phase booster and phase C of the transformer to be tested, respectively, and its output terminal is connected to phase C of the transformer to be tested through the C-phase current booster and the C-phase standard current transformer in sequence.

3. According to claim 2, the said transformer error detection wiring circuit is characterized in that: The said transformer to be tested comprises three voltage transformers to be tested and one current transformer to be tested; The input terminals of the three voltage transformers to be tested and the current transformer to be tested are SP1A, SP1B, SP1C, respectively, and the output terminals are SP2A, SP2B, SP2C respectively. The said input terminals of P1A, P1B, and P1C are connected with SP1A, SP1B, and SP1C respectively, and the output terminals are connected with SP2A, SP2B, and SP2C respectively.

4. A switching device based on the transformer error detecting wiring circuit is characterized in including a lead wire terminal. The said lead wire terminal includes a BN terminal, a CN terminal, and a P1B terminal, wherein the said BN, CN and the P1B terminals are sequentially disposed, and the center point connections of the terminal ports of the three terminals are in the same straight line. A changeover switch is also included, which includes a linear push rod and an electric motor, the axis of the said linear push rod being parallel to the said straight line, wherein the linear push rod includes an upper section (2), a middle section (3), and a lower section (4). The said upper section (2) is a metal conductor, the middle section (3) and the lower section (4) are both insulators, and the end of the lower section (4) is connected to the output shaft of the drive motor (8), where: When the driving motor (8) rotates forward, the said linear push rod approaches its P1B terminal (7) along its axial direction. When the upper section (2) of the linear push rod is in contact with the CN terminal (6) and the P1B terminal (7) simultaneously, the error detection for the instrument transformer in distribution power grid using three-phase three-wire method is performed using the three-phase detection method. When the drive motor (8) rotates reverse, the said linear push rod moves toward the BN terminal (5) along its axial direction; When the upper section (2) of the linear push rod is in contact with the BN terminal (5) and the CN terminal (6) simultaneously, the error detection for the instrument transformer in distribution power grid with three-phase four-wire method is performed using the three-phase detection method.

5. According to claim 4, the said switching device based on the transformer error detecting wiring circuit is characterized in that the connections of the upper section (2), the middle section (3) and the lower section (4) are dismantlable.

6. According to claim 5, the said switching device based on the transformer error detecting wiring circuit is characterized in that the said upper section (2), the middle section (3) and the lower section (4) are connected by a buckle.

7. According to claim 4, the said switching device based on the transformer error detecting wiring circuit is characterized in that the rod wall of the said middle section (3) is engraved with radial insulation stripes.

8. According to claim 7, the said switching device based on the transformer error detecting wiring circuit is characterized in that the said radial insulation stripes are wavy or sawtooth.

9. According to claim 4, the said switching device based on the transformer error detecting wiring circuit is characterized in that a wireless communication module and a control chip are further installed on the driving motor (8), and the said driving motor (8) and the wireless communication module are respectively connected to the control chip, wherein: The said wireless communication module is configured to receive wireless driving signals and transmit the wireless driving signals to the control chip; The said control chip is used to receive the wireless driving signals transmitted by the wireless communication module, and to send forward driving signals or reverse driving signals to the driving motor (8); The said driving motor (8) is used to receive forward rotation driving signals or reverse driving signals sent by the control chip, and to control the driving motor (8) to rotate forward or reverse.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings illustrated herein are intended to provide a further understanding of the embodiments of the invention, form part of this application, and do not constitute a limitation of the embodiments of the invention. In the drawings:

[0026] FIG. 1 is the wiring circuit diagram of a three-phase three-wire method for error detection of a transformer in this invention;

[0027] FIG. 2 is the wiring circuit diagram of the three-phase four-wire method for error detection of a transformer in this invention;

[0028] FIG. 3 is the schematic view showing the arrangement of the terminals of the lead wires in this invention;

[0029] FIG. 4 is the schematic structural view of the changeover switch in a three-phase three-wire mod in this invention;

[0030] FIG. 5 is the schematic structural view of the changeover switch in a three-phase four-wire mode in this invention;

[0031] FIG. 6 is the schematic diagram of wireless driving control of the driving motor in this invention.

MARKS AND CORRESPONDING PART NAMES IN THE DRAWING

[0032] 2Upper Section, 3Middle Section, 4Lower Section, 5BN Terminal, 6CN Terminal, 7P1B Terminal, 8Driving Motor.

DETAILED IMPLEMENTATION METHODS

[0033] In order to further clarify the objects, technical solutions and advantages of the present invention, the present invention will be further described in details below with reference to the embodiments and the accompanying drawings. The illustrative embodiments of the present invention and the description thereof are merely illustrative of the invention and are not intended to limit the invention.

Implementing Example 1

[0034] As shown in FIG. 12, this invention relates to a transformer error detection wiring circuit, including a transformer to be tested, and also including A, B, C three-phase standard voltage transformers and A, B, C three-phase boosters. One end of the said A-phase standard voltage transformer is connected to the P1A terminal, and another end is connected to the AN terminal; One end of the said B-phase standard voltage transformer is connected to the P1B terminal, and another end is connected to the BN terminal; One end of the said C phase standard voltage transformer is connected to the P1B terminal, and another end is connected to the CN terminal; P1A, P1B, and P1C are the high-voltage-end terminals of the primary side of the A, B, and C phase of the boosters, respectively, and the AN, BN, and CN are the low-voltage-end terminals of the primary side of the A, B, and C phase of the boosters, respectively; The said AN terminal is short-circuited with the CN terminal, the BN terminal is grounded, and the P1A, P1B, and P1C terminals are connected to the transformer to be tested respectively, where:

[0035] When the P1B terminal is connected to the short wiring of the CN terminal and the AN terminal, the error detection for an instrument transformer in distribution power grid with three-phase three-wire method is performed using the three-phase detection method;

[0036] When the BN terminal is connected to the short wiring of the CN terminal and the AN terminal, the error detection for an instrument transformer in distribution power grid with three-phase four-wire method is performed using the three-phase detection method. It also includes A, B, C three-phase current boosters, and A, B, C three-phase standard current transformers. The said input terminal of P1A is also connected to the A-phase booster and phase A of the transformer to be tested, respectively, and its output terminal is connected to phase A of the transformer to be tested through the A-phase current booster and the A-phase standard current transformer in sequence; The said input terminal of P1B is also connected to the B-phase booster and phase B of the transformer to be tested, respectively, and its output terminal is connected to phase B of the transformer to be tested through the B-phase booster and the B-phase standard current transformer in sequence; The said input terminal of P1C is also connected to the C-phase booster and phase C of the transformer to be tested, respectively, and its output terminal is connected to the phase C of the transformer to be tested through the C-phase current transformer and the C-phase standard current transformer. The said transformers to be tested comprise three voltage transformers to be tested and one current transformer to be tested; The input terminals of the three voltage transformers to be tested and the current transformer to be tested are SP1A, SP1B, SP1C, respectively, and the output terminals are SP2A, SP2B, SP2C, respectively. The said input terminals of P1A, P1B, and P1C are connected with SP1A, SP1B, and SP1C respectively, and the output terminals are connected with SP2A, SP2B, and SP2C respectively. In the Figures, P1A, P2A, and P3A are the A-phase high-voltage-end terminals of the primary side, and AN is the A-phase low-voltage-end terminal of the primary side; P1B, P2B, and P3B are the B-phase high-voltage-end terminals of the primary side, and BN is the B-phase low-voltage-end terminal of the primary side; P1C, P2C, and P3C are the C-phase high-voltage-end terminals of the primary side, and CN is the C-phase low-voltage-end terminal of the primary side. These terminals are extracted fully insulated. Through the above circuit structure, and compared with the prior art, the conversion of the two methods is realized in this invention by simply switching the short circuit wiring of the P1B terminal or the BN terminal to the CN terminal and the AN terminal. Using certain measurement method, each phase of the transformer to be tested can be measured simultaneously, which improves the accuracy of the detected data.

Implementing Example 2

[0037] As illustrated in FIG. 15, in this invention, the switching device based on the transformer error detecting wiring circuit includes a lead wire terminal. The said lead wire terminal includes a BN terminal, a CN terminal, and a P1B terminal, wherein the said BN, CN and the P1B terminals are sequentially disposed, and the center point connection lines of the terminal ports of the three terminals are in the same straight line. The changeover switch is also included, which includes a linear push rod and a driving motor, and the axis of the said linear push rod is parallel to the said straight line, wherein the linear push rod includes an upper section (2), a middle section (3), and a lower section (3). The said upper section (2) is a metal conductor, the middle section (3) and the lower section (4) are both insulators, and the end of the lower section (4) is connected to the output shaft of the drive motor (8), where:

[0038] When the driving motor (8) rotates forward, the said linear push rod approaches its P1B terminal (7) along its axial direction. When the upper section (2) of the linear push rod is in contact with the CN terminal (6) and the P1B terminal (7) simultaneously, the error detection for the instrument transformer in distribution power grid with three-phase three-wire method is performed using the three-phase detection method;

[0039] When the drive motor (8) rotates reverse, the said linear push rod moves toward the BN terminal (5) along its axial direction; When the upper section (2) of the linear push rod is in contact with the BN terminal (5) and the CN terminal (6) simultaneously, the error detection for the instrument transformer in distribution power grid with three-phase four-wire method is performed using the three-phase detection method. The connections of the said upper section (2), the middle section (3) and the lower section (4) are dismantlable. The said upper section (2), the middle section (3) and the lower section (4) are connected by a buckle. The rod wall of the said middle section (3) is engraved with radial insulation stripes. The said radial insulation stripes are wavy or sawtooth. Through above methods, the existing two-step wiring procedure is reduced to one step during measurement, and the primary wiring can be switched conveniently under different wiring modes when the error detection of a transformer in distribution power grid is performed, which can be realized by simply controlling the forward and reverse rotation of the driving motor (8). No manual wiring operation is required, which is safer and more convenient, and greatly improves the efficiency of wiring conversion during measurement.

Implementing Example 3

[0040] As illustrated in FIG. 6, in the said switching device of this invention based on the transformer error detecting wiring circuit, on the bases of Implementing Example 2, a wireless communication module and a control chip are further installed on the driving motor (8), and the said driving motor (8) and the wireless communication module are respectively connected to the control chip, wherein:

[0041] The said wireless communication module is configured to receive wireless driving signals and transmit the wireless driving signals to the control chip;

[0042] The said control chip is used to receive the wireless driving signals transmitted by the wireless communication module, and to send forward driving signals or reverse driving signals to the driving motor (8);

[0043] The said driving motor (8) is used to receive forward rotation driving signals or reverse driving signals sent by the control chip, and to control the driving motor (8) to rotate forward or reverse. Above structure enables the forward and reverse rotation of the driving motor that can be wirelessly controlled, and makes the measurement safer, more user-friendly and more intelligent.

[0044] Above detailed implementing methods further provides detailed explanation of the purpose, technical solutions and beneficial effects of this invention. It should be understood that the above description is only specific embodiments of this invention and is not intended to limit the scope of this invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of this invention shall be included in the scope of protection of this invention.