Fast calibration method for the remote line on the secondary side of a transformer

Abstract

The present invention discloses a method for quickly calibrating a remote line on the secondary side of a transformer. The method comprises the following steps: S1, connecting the phase line on the secondary side of the transformer to the busbar in the low-voltage switchgear through a cable; S2, connecting the busbar of the b-phase cable to the negative pole of the DC power supply through a wire; S3, sliding the other end of the detection line on the thread of the fixing bolt of the busbar of the a-phase cable, and the wiring of the a-phase cable and the b-phase cable is correct; S4, when there is no electric spark between the detection line and the fixing bolt, the a-phase cable and the b-phase cable are in a short-circuit state; S5, repeating S2-S4 to detect the b-phase cable and the c-phase cable; S6, repeating S2-S4 to detect the c-phase cable and the neutral cable; S7, repeating S2-S4 to detect the a-phase cable and the neutral cable; S8, determining the phase sequence of the a-phase line; S9, repeating S8 to determine the phase sequences of the b-phase line and the c-phase line. The detection process of the present invention is simple, which improves the work efficiency.

Description

Technical Field

[0001] The present invention relates to a transformer, in particular to a method for quickly calibrating a remote line on the secondary side of a transformer. Background Art

[0002] In the construction of transformers and power transmission and transformation sites in mechatronic engineering, multi-core connections of multi-strand hard-core cables are usually used for the secondary side of the transformer and the main incoming line of the low-voltage switchgear. Since the color-coded lines of polyvinyl chloride multi-core cables are relatively thin, it is extremely easy to misconnect the phase sequences when the multi-core cables are connected for a, b, and c phases multiple times. Failure to check properly will cause large-scale accidents such as phase-to-phase short circuits. Calibration must be carried out before power-on after wiring. A large amount of labor and time are consumed during disassembly, installation, and verification, seriously affecting the progress of power supply and distribution. Summary of the Invention

[0003] The present invention aims to solve the above technical problems, and thus provides a method for quickly calibrating a remote line on the secondary side of a transformer that is safe and highly efficient.

[0004] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0005] A method for quickly calibrating a remote line on the secondary side of a transformer includes the following steps:

[0006] S1. Connect the phase wires on the secondary side of the transformer to the busbars in the low-voltage switchgear through cables;

[0007] S2. Connect the busbar of the b-phase cable to the negative pole of the DC power supply through a wire, connect the positive pole of the DC power supply to one end of the detection wire, and connect the detection wire in series with an indicator light;

[0008] S3. Slide the other end of the detection wire on the thread of the fixing bolt of the busbar of the a-phase cable. When there is an electric spark, the a-phase cable and the b-phase cable are in an open circuit state, and the connection of the a-phase cable and the b-phase line cable is correct;

[0009] S4. When there is no electric spark between the detection wire and the fixing bolt, the a-phase cable and the b-phase cable are in a short circuit state, and the core wires of the a-phase line cable and the b-phase line cable are misconnected. Find the misconnected core wires of the cable;

[0010] S5. Repeat S2-S4 to detect the b-phase line cable and the c-phase line cable;

[0011] S6. Repeat S2-S4 to detect the c-phase line cable and the neutral line cable;

[0012] S7. Repeat S2-S4 to detect the a-phase line cable and the neutral line cable;

[0013] S8. Determine the phase sequence of the a-phase line

[0014] Short-circuit phase a wire with the neutral wire N on the transformer side. Connect a wire, a DC power supply, a detection wire, and an indicator light in series to the terminal of the neutral wire cable in the low-voltage cabinet in sequence. The detection wire slides on the fixing bolt of the terminal of phase a cable. If there is an electric spark, it means that the phase sequence in the low-voltage cabinet is wrongly connected. If there is no electric spark, it means that the connection of phase a wire is correct.

[0015] S9. Repeat S8 to determine the phase sequences of phase b wire and phase c wire.

[0016] Compared with the prior art, the beneficial effects of the present invention adopting the above technical solution are as follows:

[0017] Utilize the inductance working characteristic of the transformer equipment itself to form a discharge phenomenon for detection. The detection process is simple, saving a large amount of time and cost for manual disassembly and assembly, improving work efficiency, protecting the cable from damage caused by secondary disassembly and assembly, extending the service life of the cable, and ensuring the project quality; with a high safety factor, avoiding the occurrence of large-scale short-circuit accidents.

[0018] Furthermore, the optimized solution of the present invention is:

[0019] The DC power supply is a battery.

[0020] The voltage of the DC power supply is 3 volts.

[0021] The indicator light is an electric bulb. Description of the Drawings

[0022] Figure 1 is a schematic diagram of the non-shorted phase wires in the embodiment of the present invention;

[0023] Figure 2 is Figure 1 the equivalent circuit schematic diagram of the detection circuit;

[0024] Figure 3 is a schematic diagram of the shorted phase wires in the embodiment of the present invention;

[0025] Figure 4 is Figure 3 the equivalent circuit schematic diagram of the detection circuit.

[0026] In the figure: Transformer 1; Primary winding 1-1; Secondary winding 1-2; Phase a cable 2; Core wire 2-1; Phase b cable 3; Phase c cable 4; Neutral wire cable 5; Busbar 6; Wire 7; DC power supply 8; Detection wire 9; Indicator light 10; Low-voltage cabinet 11. Detailed Embodiment

[0027] The present invention will be further described in detail below with reference to the drawings and embodiments.

[0028] See Figures 1 - 4, this embodiment is a method for quickly calibrating the remote line on the secondary side of a transformer, which is carried out according to the following steps:

[0029] S1. The transformer 1 is mainly composed of a primary winding 1-1 and a secondary winding 1-2. After the transformer 1 is installed, the a-phase wire, b-phase wire, c-phase wire, and neutral wire N of the secondary winding 1-2 on the secondary side of the transformer 1 are respectively connected to the four terminal blocks of the busbar 6 in the low-voltage cabinet 11 through the a-phase cable 2, b-phase cable 3, c-phase cable 4, and neutral cable 5.

[0030] S2. Connect the terminal block of the busbar 6 of the b-phase cable 3 to the negative pole of the DC power supply 8 through the wire 7. Connect the positive pole of the DC power supply 8 to one end of the detection wire 9. The detection wire 9 is connected in series with the indicator light 10. The indicator light 10 uses a 3.8V bulb, and the DC power supply 8 uses two 1.5V batteries connected in series.

[0031] S3. Slide the other end of the detection wire 9 on the thread of the fixing bolt of the terminal block of the busbar 6 of the a-phase cable 2. When the indicator light 10 lights up and there is an electric spark, it means that the b-phase cable 3 and the a-phase cable 2 are in an open circuit state, and the connection between the a-phase cable 2 and the b-phase wire cable 3 is accurate ( Figure 1 、 Figure 2 as shown). When the line connection is accurate, the two windings and the line of the transformer 1 form a closed-loop inductive circuit. When there is an exciting current flowing through the secondary circuit of the transformer 1, an electromagnetic field is generated. By using the sliding of the concave and convex threads of the fixing bolt, the charging and discharging processes of the inductive circuit are completed, so there will be a discharge spark during sliding.

[0032] S4. When there is no electric spark between the detection wire 9 and the fixing bolt ( Figure 3 、 Figure 4 as shown) and the indicator light 10 lights up, it means that the a-phase cable 2 and the b-phase wire cable 3 are in a short circuit state, and the core wire 2-1 of the a-phase cable 2 and the b-phase wire cable 3 is wrongly connected. Find the wrongly connected core wire 2-1 of the cable. When the core wire 2-1 of the cable is wrongly connected, the line is short-circuited, and a large current in the loop will flow back through the short-circuit loop of the core wire 2-1 of the cable. The secondary side loop of the transformer 1 in parallel with it cannot generate an electromagnetic field using the exciting current, so the charging and discharging processes of the inductive circuit cannot be completed through the sliding of the concave and convex threads of the connection bolt, that is, the discharge phenomenon cannot be formed.

[0033] S5. Repeat S2 - S4 to detect the b-phase wire cable 3 and the c-phase cable 4.

[0034] S6. Repeat S2 - S4 to detect the c-phase cable 4 and the neutral cable 5.

[0035] S7. Repeat S2 - S4 to detect the a-phase cable 2 and the neutral cable 5.

[0036] S8, Determination of the phase sequence of the a-phase line

[0037] Short-circuit the a-phase line and the neutral line N on the 1 side of the transformer. Connect the wire terminals of the neutral line cable 5 in the low-voltage cabinet 11 in series with a wire 7, a DC power supply 8, a detection wire 9, and an indicator light 10 in sequence. The detection wire 9 slides on the fixing bolt of the wire terminal of the a-phase cable 2. If there is an electric spark, it means that the phase sequence in the low-voltage cabinet 11 is connected wrongly. If there is no electric spark, the connection of the a-phase line is correct;

[0038] S9, Repeat S8 to detect the phase sequences of the b-phase line and the c-phase line.

[0039] The present invention uses two 1.5V dry batteries, a 3.8V electric bulb and a thin cable connected in series to make a calibration power supply. At the incoming cable of the low-voltage cabinet in the power distribution room, use the thin cable on the calibration power supply to slide on the concave-convex thread of the wiring fixing bolt, and utilize the inductance working characteristics of the transformer equipment itself to charge and discharge the secondary side of the transformer and the incoming cable. Determine whether there is a short circuit in the line by whether a spark is generated. The present invention can not only quickly, simply and safely complete the calibration of the remote line on the secondary side of the transformer, but also be applicable to the calibration of the remote line of inductive and capacitive devices such as multi-strand line motors.

[0040] The above are only the preferred and feasible embodiments of the present invention, and do not limit the scope of the rights of the present invention accordingly. Any equivalent structural changes made by using the content of the specification and drawings of the present invention are included in the scope of the rights of the present invention.

Claims

1. A rapid calibration method for the remote line on the secondary side of a transformer, comprising the following steps: S1. Connect the phase wire on the secondary side of the transformer to the busbar in the low-voltage switchgear through a cable. S2. Connect the busbar of the b-phase cable to the negative pole of the DC power supply through a wire, connect the positive pole of the DC power supply to one end of the detection wire, and connect the detection wire in series with an indicator light. S3. Slide the other end of the detection wire on the thread of the fixing bolt of the busbar of the a-phase cable. When there is an electric spark, the a-phase cable and the b-phase cable are in an open circuit state, and the wiring of the a-phase cable and the b-phase line cable is correct. S4. When there is no electric spark between the detection wire and the fixing bolt, the a-phase cable and the b-phase cable are in a short circuit state, and the core wires of the a-phase line cable and the b-phase line cable are wrongly connected. Locate the wrongly connected core wire of the cable. S5. Repeat S2 - S4 to detect the b-phase line cable and the c-phase line cable. S6. Repeat S2 - S4 to detect the c-phase line cable and the neutral line cable. S7. Repeat S2 - S4 to detect the a-phase line cable and the neutral line cable. S8. Determine the phase sequence of the a-phase line Short-circuit the a-phase line and the neutral line N on the transformer side. Connect a wire, a DC power supply, a detection wire, and an indicator light in series in sequence at the terminal of the neutral line cable in the low-voltage switchgear. Slide the detection wire on the fixing bolt of the terminal of the a-phase cable. If there is an electric spark, the phase sequence in the low-voltage switchgear is wrongly connected. If there is no electric spark, the wiring of the a-phase line is correct. S9. Repeat S8 to determine the phase sequences of the b-phase line and the c-phase line.

2. The rapid calibration method for the remote line on the secondary side of a transformer according to claim 1, characterized in that: The DC power supply is a battery.

3. The rapid calibration method for the remote line on the secondary side of a transformer according to claim 1, characterized in that: The voltage of the DC power supply is 3 volts.

4. The rapid calibration method for the remote line on the secondary side of a transformer according to claim 1, characterized in that: The indicator light is an electric bulb.

Images