Metering wiring circuit of three-phase two-element electric energy meter

Abstract

The utility model relates to the technical field of substation electric energy metering, and particularly discloses a three-phase two-element electric energy meter metering wiring circuit, which comprises an electric energy meter body and an electric energy meter metering wiring box, the element I comprises an A-phase secondary measurement current coil, an A-phase secondary measurement voltage coil and a B-phase secondary measurement voltage coil, the element II comprises a C-phase secondary measurement current coil, a B-phase secondary measurement voltage coil and a C-phase secondary measurement voltage coil, and the electric energy meter metering junction box is provided with a voltage connecting piece and a current connecting piece. A wiring terminal on one side of the electric energy meter metering junction box is connected with a wiring terminal of the electric energy meter body, and a wiring terminal on the other side of the electric energy meter metering junction box is connected with a voltage transformer secondary measurement voltage winding and a current transformer secondary measurement current winding; when the electric energy meter needs to be replaced, the electric energy meter replacing device has the advantages of simple operation, high efficiency, safety and reliability.

Description

Technical Field

[0001] The utility model relates to the technical field of electric energy metering in transformer substations, in particular to a three-phase two-element electric energy meter metering wiring circuit. Background Art

[0002] Due to the symmetry of the three-phase loads in substations, high-voltage power supply systems are typically equipped with three-phase, two-element energy meters to measure the electrical consumption of substation users. The operating principle is to connect the secondary currents of phases A and C of the high-voltage current transformer to the current coil of the energy meter, and the secondary voltages of phases A, B, and C of the voltage transformer to the voltage coil of the energy meter. The secondary voltage and secondary current are combined to achieve energy measurement.

[0003] like Figure 1 As shown, the three-phase two-element electric energy meter measurement wiring circuit in the prior art mainly includes the secondary voltage winding of the voltage transformer, the secondary measurement current winding of the current transformer, the electric energy meter body, wires, etc. The working principle of the electric energy meter measurement wiring circuit is as follows:

[0004] The three-phase secondary voltage measurement windings of phase A, phase B and phase C of the voltage transformer are connected to the three-phase secondary voltage connection terminals a, d and g of the electric energy meter body respectively through the secondary voltage measurement circuit breaker 1DK of the voltage transformer;

[0005] The A-phase secondary measurement current Ia* and Ia of the current transformer are connected to the connection terminals b and c of the A-phase secondary measurement current coil of element I of the electric energy meter body through the secondary measurement current terminals S1 and S2 and the secondary measurement current wires respectively; the C-phase secondary measurement current Ic* and Ic of the current transformer are connected to the connection terminals e and f of the C-phase secondary measurement current coil of element II of the electric energy meter body through the secondary measurement current terminals S1 and S2 and the secondary measurement current wires respectively.

[0006] The A-phase secondary measurement current Ia of the current transformer and the C-phase secondary measurement current Ic of the current transformer are short-circuited at the secondary current terminal block of the control cabinet door through a dedicated current shorting metal sheet and then reliably connected to the secondary current grounding wire.

[0007] In the existing technology, electricity meters need to be calibrated after years of use or replaced after a fault. We know that the secondary current circuit of the electricity meter is not allowed to be open. The usual practice is to replace it after the high-voltage equipment is powered off, or to use a special shorting wire on the current terminal block to short-circuit the secondary current and ground it, and then perform a clamp current test to confirm the secondary current circuit of the electricity meter. It is also necessary to disconnect the secondary side circuit breaker of the voltage transformer or remove the secondary side three-phase voltage fuse, and perform an electrical test at the secondary voltage terminal of the electricity meter. Only after taking the above measures can the electricity meter be replaced. After the replacement is completed, the relevant safety measures are removed and the corresponding terminal is tightened. There is a complex operation process. There is shunt current in the secondary current circuit of the electricity meter. Disconnecting the secondary circuit breaker of the voltage transformer may also cause problems such as loss of secondary measurement voltage and protection for a short time, and the operation risk is high.

[0008] Therefore, it is necessary to design a three-phase two-element electric energy meter measurement wiring circuit to solve the problems of complex operation process and high operation risk of existing electric energy meters. Utility Model Content

[0009] In view of the problems existing in the prior art, the purpose of the present invention is to provide a three-phase two-element electric energy meter measurement wiring circuit.

[0010] The technical solution adopted by the utility model to solve its technical problems is: a three-phase two-element electric energy meter measurement wiring circuit, including an electric energy meter body and an electric energy meter measurement junction box, the electric energy meter body includes element I and element II, element I includes an A-phase secondary measurement current coil, an A-phase secondary measurement voltage coil and a B-phase secondary measurement voltage coil, element II includes a C-phase secondary measurement current coil, a B-phase secondary measurement voltage coil and a C-phase secondary measurement voltage coil, the electric energy meter measurement junction box is provided with a voltage connecting piece and a current connecting piece, one side terminal of the electric energy meter measurement junction box is connected to the terminal of the electric energy meter body, and the other side terminal of the electric energy meter measurement junction box is connected to the secondary measurement voltage winding of the voltage transformer and the secondary measurement current winding of the current transformer.

[0011] Specifically, the voltage transformer secondary measurement voltage winding includes an A-phase secondary measurement voltage winding, a B-phase secondary measurement voltage winding, a C-phase secondary measurement voltage winding and a secondary side voltage circuit breaker, and the secondary side voltage circuit breaker controls the on and off of the three-phase secondary voltage of the voltage transformer.

[0012] Specifically, the A-phase secondary voltage measurement winding is connected to the Ua secondary voltage terminal of the energy meter measurement junction box through a secondary side voltage circuit breaker via a wire;

[0013] The B-phase secondary voltage winding is connected to the Ub secondary voltage terminal of the energy meter junction box via a wire through a secondary voltage circuit breaker;

[0014] The C-phase secondary measurement voltage winding is connected to the Uc secondary voltage terminal of the energy meter measurement junction box through a wire via a secondary side voltage circuit breaker.

[0015] Specifically, the secondary measuring current winding of the current transformer includes an A-phase secondary measuring current winding and a C-phase secondary measuring current winding. The A-phase secondary measuring current winding is connected to the A-phase secondary current terminal on the electric energy meter measurement junction box through a wire; the C-phase secondary measuring current winding is connected to the C-phase secondary current terminal on the electric energy meter measurement junction box through a wire.

[0016] Specifically, three voltage connection pieces and four current connection pieces are provided in the electricity meter measurement junction box. The voltage of the secondary measurement voltage winding of the voltage transformer is connected to the secondary measurement voltage terminal of the electricity meter body through the voltage connection piece of the electricity meter measurement junction box, and the current of the secondary measurement current winding of the current transformer is connected to the secondary measurement current terminal of the electricity meter body through the current connection piece of the electricity meter measurement junction box.

[0017] Specifically, the wire connecting the secondary voltage measuring winding of the voltage transformer to the energy meter junction box adopts a cross-section of 1.5mm 2 Single copper core wire.

[0018] Specifically, the wire connecting the secondary current measuring winding of the current transformer to the electric energy meter measurement junction box adopts a cross-section of 2.5mm 2 Single copper core wire.

[0019] The utility model has the following beneficial effects:

[0020] The three-phase two-element electric energy meter measurement wiring circuit designed by the utility model does not need to shut down the high-voltage equipment, or use a special short-circuit wire on the current terminal block to short-circuit the secondary current and perform grounding treatment when the electric energy meter needs to be replaced. It only needs to disconnect the three voltage connecting pieces in the electric energy meter measurement junction box, and short-circuit the two current connecting pieces of the A and C phases to measure the secondary input and output current of the A phase and the secondary input and output current of the C phase respectively; the electric energy meter can be replaced. The utility model has the advantages of simple operation, high efficiency, safety and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The invention discloses a measurement wiring circuit diagram of a three-phase two-element electric energy meter in the prior art.

[0022] Figure 2 The utility model provides a three-phase two-element electric energy meter measurement wiring circuit diagram.

[0023] In the figure: 1 - electric energy meter body, 1.1 - A phase secondary current measuring coil, 1.2 - C phase secondary current measuring coil, 1.3 - A phase secondary voltage measuring coil, 1.4 - B phase secondary voltage measuring coil, 1.5 - C phase secondary voltage measuring coil;

[0024] 2-Energy meter junction box, 2.1-Voltage connector, 2.2-Current connector;

[0025] 3-voltage transformer secondary voltage measurement winding, 3.1-A phase secondary voltage measurement winding, 3.2-B phase secondary voltage measurement winding, 3.3-C phase secondary voltage measurement winding, 3.4-secondary side voltage circuit breaker;

[0026] 4-Current transformer secondary measurement current winding, 4.1-A phase secondary measurement current winding, 4.2-C phase secondary measurement current winding. DETAILED DESCRIPTION

[0027] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely further describe the technical solutions in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] like Figure 2 As shown, a three-phase two-element electric energy meter measurement wiring circuit includes an electric energy meter body 1, an electric energy meter measurement junction box 2, a voltage transformer secondary measurement voltage winding 3, and a current transformer secondary measurement current winding 4. The electric energy meter body 1 includes element I and element II as well as secondary voltage wiring terminals and secondary current wiring terminals. Element I includes an A-phase secondary measurement current coil 1.1, an A-phase secondary measurement voltage coil 1.3, and a B-phase secondary measurement voltage coil 1.4. Element II includes a C-phase secondary measurement current coil 1.2, a B-phase secondary measurement voltage coil 1.4, and a C-phase secondary measurement voltage coil 1.5.

[0029] The electric energy meter measurement junction box 2 is provided with Ua secondary voltage terminal, Ub secondary voltage terminal, Uc secondary voltage terminal, A phase secondary current terminal, C phase secondary current terminal, three voltage connecting pieces 2.1 and four current connecting pieces 2.2. The secondary voltage of the voltage transformer secondary measurement voltage winding 3 is connected to the secondary measurement voltage terminal of the electric energy meter body 1 through the voltage connecting piece 2.1 of the electric energy meter measurement junction box 2, and the secondary current of the current transformer secondary measurement current winding 4 is connected to the secondary measurement current terminal of the electric energy meter body 1 through the current connecting piece 2.2 of the electric energy meter measurement junction box 2.

[0030] The connection terminals on one side of the energy meter junction box 2 are connected to the connection terminals of the energy meter body 1 , and the connection terminals on the other side of the energy meter junction box 2 are connected to the secondary voltage measurement winding 3 of the voltage transformer and the secondary current measurement winding 4 of the current transformer.

[0031] The voltage transformer secondary measuring voltage winding 3 comprises an A-phase secondary measuring voltage winding 3.1, a B-phase secondary measuring voltage winding 3.2, a C-phase secondary measuring voltage winding 3.3 and a secondary side voltage breaker 3.4. The secondary side voltage breaker 3.4 controls the on and off of the three-phase secondary voltage of the voltage transformer.

[0032] The A-phase secondary voltage measurement winding 3.1 is connected to the Ua secondary voltage terminal of the energy meter measurement junction box 2 through a wire via the secondary side voltage circuit breaker 3.4; the B-phase secondary voltage measurement winding 3.2 is connected to the Ub secondary voltage terminal of the energy meter measurement junction box 2 through a wire via the secondary side voltage circuit breaker 3.4; the C-phase secondary voltage measurement winding 3.3 is connected to the Uc secondary voltage terminal of the energy meter measurement junction box 2 through a wire via the secondary side voltage circuit breaker 3.4.

[0033] The current transformer secondary measurement current winding 4 includes an A-phase secondary measurement current winding 4.1 and a C-phase secondary measurement current winding 4.2. The A-phase secondary measurement current winding 4.1 is connected to the A-phase secondary current terminal on the electric energy meter measurement junction box 2 through a wire; the C-phase secondary measurement current winding 4.2 is connected to the C-phase secondary current terminal on the electric energy meter measurement junction box 2 through a wire.

[0034] The cross-section of the wire used for connecting the secondary voltage transformer winding 3 to the energy meter junction box 2 is 1.5mm 2 Single copper core wire.

[0035] The cross-section of the wire used for connecting the secondary current transformer winding 4 to the energy meter junction box 2 is 2.5mm 2 Single copper core wire.

[0036] A method for operating a three-phase two-element electric energy meter measurement wiring circuit comprises the following steps:

[0037] 1. The A-phase secondary voltage measurement winding, the B-phase secondary voltage measurement winding, and the C-phase secondary voltage measurement winding are first connected to the secondary side voltage circuit breaker of the voltage transformer in the control cabinet through wires, and then respectively connected to the Ua secondary voltage terminal, Ub secondary voltage terminal, and Uc secondary voltage terminal of the electric energy meter measurement junction box. After passing through the voltage connecting piece in the electric energy meter measurement junction box, they are respectively connected to the secondary voltage measurement terminal a, secondary voltage measurement terminal d, and secondary voltage measurement terminal g of the three-phase secondary voltage of the electric energy meter body.

[0038] 2. The secondary measuring current Ia* output by the A-phase secondary measuring current winding passes through the secondary measuring current terminal S1 on the current transformer body, and is first connected to the A-phase secondary measuring current A411 of the secondary current terminal block inside the control cabinet door through the secondary current wire, and then is connected to the A-phase secondary measuring current incoming wiring terminal inside the energy meter measurement junction box through the wire, and then passes through the A-phase L wiring terminal inside the energy meter measurement junction box, and is then connected to the A-phase secondary measuring current coil wiring terminal b of the element I of the energy meter body through the secondary current wire. The wiring terminal b is connected to the A-phase secondary measuring current coil of the energy meter body through the A-phase secondary measuring current terminal inside the energy meter body. The measuring current coil is connected to the terminal c, and the terminal c is connected to the secondary current terminal inside the electric energy meter measurement junction box through the secondary measuring current wire. After passing through the M terminal and current connecting piece M and current connecting piece N of phase A in the electric energy meter measurement junction box, it passes through the secondary measuring current outlet terminal of phase A, and is connected to the A-phase secondary measuring current A412 of the secondary current terminal block in the control cabinet door through the secondary current wire. It is then connected to the A-phase secondary measuring current terminal S2 on the current transformer body through the secondary current wire, and finally connected to the secondary measuring current Ia of the phase A secondary measuring current winding.

[0039] 3. The secondary measurement current Ic* output by the C-phase secondary measurement current winding passes through the secondary measurement current terminal S1 on the current transformer body, and is first connected to the C-phase secondary measurement current C411 of the secondary current terminal block inside the control cabinet door through the secondary current wire, and then is connected to the C-phase secondary measurement current input terminal inside the energy meter measurement junction box through the wire, and then passes through the C-phase L terminal inside the energy meter measurement junction box, and is then connected to the C-phase secondary measurement current coil terminal e of the element II of the energy meter body through the secondary current wire. The terminal e is connected to the C-phase secondary measurement current coil terminal e of the energy meter body through the C-phase secondary measurement current terminal The measuring current coil is connected to the terminal f, and the terminal f is connected to the secondary current terminal inside the electric energy meter measurement junction box through the secondary measuring current wire. After passing through the M terminal and current connecting piece M and current connecting piece N of phase C in the electric energy meter measurement junction box, it passes through the secondary measuring current outlet terminal of phase C, and is connected to the C phase secondary measuring current C412 of the secondary current terminal block in the control cabinet door through the secondary current wire. It is then connected to the C phase secondary measuring current terminal S2 on the current transformer body through the secondary current wire, and finally connected to the secondary measuring current Ic of the phase C secondary measuring current winding.

[0040] 4. The A-phase secondary measurement current A412 of the current transformer and the C-phase secondary measurement current C412 of the current transformer are short-circuited at the secondary current terminal block of the control cabinet door through a dedicated current shorting metal sheet and then reliably connected to the secondary current grounding wire N412.

[0041] The utility model provides a three-phase, two-element electric energy meter measurement wiring circuit. When replacing an electric energy meter, there is no need to shut down the high-voltage equipment or use special shorting wires on the current terminal block to short-circuit the secondary current and ground it. Instead, the electric energy meter can be replaced by simply disconnecting the three voltage connectors 2.1 in the electric energy meter measurement junction box 2 and short-circuiting the two current connectors 2.2 of phases A and C, respectively, to measure the currents of the secondary incoming and outgoing wires of phase A and phase C. This circuit offers the advantages of simple operation, high efficiency, safety, and reliability.

[0042] The present invention is not limited to the above-mentioned embodiments. Anyone should be aware of the structural changes made under the inspiration of the present invention. Any technical solution that is the same or similar to the present invention falls within the scope of protection of the present invention.

[0043] The technology, shape and structure that are not described in detail in this utility model are all well-known technologies.

Claims

1. A three-phase two-element electric energy meter measurement wiring circuit, characterized in that: It includes an electric energy meter body and an electric energy meter measurement junction box. The electric energy meter body includes element I and element II. Element I includes an A-phase secondary current measurement coil, an A-phase secondary voltage measurement coil, and a B-phase secondary voltage measurement coil. Element II includes a C-phase secondary current measurement coil, a B-phase secondary voltage measurement coil, and a C-phase secondary voltage measurement coil. The electric energy meter measurement junction box is provided with a voltage connecting piece and a current connecting piece. The connection terminals on one side of the electric energy meter measurement junction box are connected to the connection terminals of the electric energy meter body, and the connection terminals on the other side of the electric energy meter measurement junction box are connected to the secondary voltage measurement winding of the voltage transformer and the secondary current measurement winding of the current transformer.

2. The three-phase two-element electric energy meter measurement wiring circuit according to claim 1, characterized in that: The voltage transformer secondary measurement voltage winding includes an A-phase secondary measurement voltage winding, a B-phase secondary measurement voltage winding, a C-phase secondary measurement voltage winding and a secondary side voltage circuit breaker, and the secondary side voltage circuit breaker controls the on and off of the three-phase secondary voltage of the voltage transformer.

3. The three-phase two-element electric energy meter measurement wiring circuit according to claim 2, characterized in that: The A-phase secondary voltage measuring winding is connected to the Ua secondary voltage terminal of the energy meter measurement junction box through a secondary side voltage circuit breaker via a wire; The B-phase secondary voltage winding is connected to the Ub secondary voltage terminal of the energy meter junction box via a wire through a secondary voltage circuit breaker; The C-phase secondary measurement voltage winding is connected to the Uc secondary voltage terminal of the energy meter measurement junction box through a wire via a secondary side voltage circuit breaker.

4. The three-phase two-element electric energy meter measurement wiring circuit according to claim 1, characterized in that: The secondary measuring current winding of the current transformer includes an A-phase secondary measuring current winding and a C-phase secondary measuring current winding. The A-phase secondary measuring current winding is connected to the A-phase secondary current terminal on the electric energy meter measurement junction box through a wire; the C-phase secondary measuring current winding is connected to the C-phase secondary current terminal on the electric energy meter measurement junction box through a wire.

5. The three-phase two-element electric energy meter measurement wiring circuit according to claim 1, characterized in that: The electric energy meter measurement junction box is provided with three voltage connection pieces and four current connection pieces. The voltage of the secondary voltage measurement winding of the voltage transformer is connected to the secondary voltage measurement terminal of the electric energy meter body through the voltage connection piece of the electric energy meter measurement junction box. The current of the secondary current measurement winding of the current transformer is connected to the secondary current measurement terminal of the electric energy meter body through the current connection piece of the electric energy meter measurement junction box.

6. The three-phase two-element electric energy meter measurement wiring circuit according to claim 1, characterized in that: The wire used to connect the secondary voltage transformer winding to the energy meter junction box is 1.5mm in cross section. 2 Single copper core wire.

7. The three-phase two-element electric energy meter measurement wiring circuit according to claim 1, characterized in that: The wire used to connect the secondary current transformer winding to the energy meter junction box is 2.5mm in cross section. 2 Single copper core wire.

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