JP2001258183A - Power supply using electrostatic induction - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To take out power without contact with an overhead ground wire in a place where it is difficult to draw in commercial power. A fixed length insulated cable (8) is connected to an overhead ground wire (6) made of a conductive wire or OPGW via a plurality of insulating spacers (7).
Are suspended in parallel. The primary winding of the transformer 10 is connected between one end of the insulated cable 8 and the ground, and the secondary winding of the transformer 10 is connected to the power supply controller 11. The power control unit includes an impedance adjustment circuit 12, a rectifier circuit 13, and a smoothing capacitor 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device using electrostatic induction, and more particularly to a power supply device installed in a power transmission tower in a place where commercial power is hardly drawn in, and having a relatively low load capacity such as an aviation obstruction light and a monitoring device. The present invention relates to a power supply device used as a small power supply.

[0002]

2. Description of the Related Art Conventionally, a so-called electromagnetic induction system or an electrostatic induction system has been used from an overhead ground wire provided alongside a power transmission main line.
Extracting electrical energy is already known. For example, as proposed by the applicant of the present invention in Japanese Patent Application Laid-Open No. 10-257699, `` Aerial Ground Line Utilizing Power Supply Device, '' for the purpose of securing the power supply of an aviation obstruction light and the like arranged on a transmission tower,
Attempts have been made to connect a current transformer (hereinafter referred to as CT) to an overhead ground wire installed in parallel with the power transmission main line, to extract and use the induced current generated by the current of the power transmission main line. In other words, the overhead ground wire is insulated and supported on one or more power transmission towers with jumpers clamps, clamp bases, insulating plates, cable-tightening plates, right angle clevis, other insulators and metal fittings, and the apparent span between the power transmission towers is extended, While preventing the current induced from the power transmission main line to the overhead ground wire from flowing to the ground and increasing the induced current, the overhead ground wire and multiple CTs are electromagnetically coupled to take in the induced current, and the CTs are connected in parallel. In addition, a stabilization circuit and a protection circuit are provided on the secondary winding of the CT, and the power is supplied to the load by mounting it on a power transmission tower. The above-mentioned power supply device utilizing an overhead ground wire by the electromagnetic induction method is intended for power transmission equipment in which a conductive overhead wire or an optical fiber composite overhead ground wire (hereinafter referred to as OPGW) is laid.

[0003]

In recent years, in power transmission facilities, an overhead ground line has been switched to an OPGW which also serves as an information communication transmission line. A power supply device using this OPGW is easy to use a through-type CT that is electromagnetically coupled to the OPGW in a non-contact manner as an electromagnetic induction type power supply CT.
A low amperage that penetrates the OPGW for one turn as the primary winding
Since it is a turn, there is a problem that sufficient power cannot be obtained unless a large number of large and heavy through-type CTs are connected. Furthermore, in general, there are many cases where a split-type CT having a two-core iron core configuration is employed, in which case, the number of steps for mounting the CT on the power transmission tower increases, and the assembly and maintenance of the iron core split mating surface becomes complicated, resulting in cost reduction. Was relatively expensive.

The applicant of the present invention is Japanese Patent Application No. Hei 10-305583.
No. “Power supply device using overhead ground wire” was proposed to use a coiled CT.In this case, however, the primary winding terminal of the CT must be directly connected to the overhead ground wire. At the time of installation on a steel tower, it was necessary to perform operations such as separating the outer conductive part, insulating treatment, or separately installing an insulating box, especially for the OPGW. Therefore, the present invention can be applied to power transmission equipment installed in a mountainous remote place or the like where it is difficult to draw in commercial power and an overhead ground line or an OPGW is installed by a conductive wire. It is an object of the present invention to provide a power supply device that efficiently and inexpensively extracts electric energy induced by capacitive coupling with a power transmission main line with simple equipment.

[0005]

Means for Solving the Problems To solve the above-mentioned problems, the invention of claim 1 is directed to a fixed length of a fixed length suspended in parallel through a plurality of insulating spacers on an overhead ground wire made of a conductive wire or an OPGW. It is characterized by comprising an insulated cable, a transformer having a primary winding connected between one end of the insulated cable and ground, and a power supply controller connected to a secondary winding of the transformer.

According to a second aspect of the present invention, there is provided an intermediate electrode which is disposed between a power transmission tower and a power transmission main line and is made of a metal plate covered with an insulator, and a primary winding is connected between the intermediate electrode and ground. It is characterized by comprising a transformer and a power supply control unit connected to a secondary winding of the transformer.

According to a third aspect of the present invention, in the first or second aspect, the primary winding, the secondary winding and the iron core of the transformer are integrally coated with an insulating resin to form an all-molded insulating transformer. Features.

[0008] The invention of claim 4 is the invention of claim 1, 2, or 3.
According to the invention, the power supply control section is constituted by an impedance adjustment circuit, a rectifier circuit, and a smoothing capacitor.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram in which a part of the embodiment according to the first aspect is exaggerated. In the figure, 1 is a power transmission tower, 2 is a power transmission main line, and is supported at a fixed point 3 by a supporting insulator chain 4. Reference numeral 5 denotes a connecting line sandwiched between the fixed points 3. An overhead ground wire 6 made of a conductive wire or an OPGW is provided above the power transmission main line 2, and an insulating cable 8 as an intermediate electrode is suspended near the power transmission tower 1 via an insulating spacer 7. As the insulating spacer 7, a molded product of an epoxy resin or a ceramic product is used. One end of the insulated cable 8 is connected to a power supply unit 9 installed on the power transmission tower 1 side. In the figure, C ₁ is the capacitance between the insulated cable 8 and the power transmission main line 2, and C ₂ is the capacitance between the insulated cable 8 and the overhead ground wire 6.

FIG. 2 is a circuit diagram showing the electrical configuration of FIG. In the figure, the insulated cable 8 has an inductance L
Is connected to one of the primary windings of the insulating transformer 10. The other of the primary windings is grounded. The secondary winding of the insulating transformer 10 is connected to the power control unit 11.
The power supply control unit 11 includes an impedance adjustment circuit 12, a rectification circuit 13, and a smoothing capacitor 14.
That is, the input from the insulating transformer 10 is impedance-adjusted by the impedance adjustment circuit 12, then rectified by the rectification circuit 13, smoothed by the smoothing capacitor 14, and sent to the load 15 such as an aviation obstacle light.

The impedance adjustment circuit 12 is configured by combining a coil, a capacitor, and a resistor.
The rectifier circuit 13 is configured by a bridge circuit combining rectifier elements. In the figure, Cg is a floating capacitance to ground generated between the insulated cable 8 and the ground. With this configuration, a voltage is generated in the insulated cable 8 as the intermediate electrode with respect to the ground in accordance with the floating capacitance to ground. As it is well known, the electrostatic capacitance C ₂ between arranged parallel conductor as in FIG. 3, the following equation.

[0012]

(Equation 1)

Here, ε ₀ is a dielectric constant in a vacuum, which is almost equal to a dielectric constant in the atmosphere. l is the length of the parallel conductor, d is the center distance between the parallel conductors, and a ₁ and a ₂ are the respective radii of the parallel conductor. From these facts, the energy W stored in the insulated cable 8 arranged as shown in FIG.

[0014]

(Equation 2)

Here, V is a shared voltage of the insulated cable 8. From these facts, the energy W increases as the length l of the parallel conductor increases, and the energy W decreases as the center distance d between the parallel conductors increases. Also, the shared voltage V
Increases in proportion to the center distance d between the parallel conductors in the range of d≪D, so that the energy W also increases in accordance with d. That is, necessary energy can be obtained by appropriately setting the distance d between the overhead ground wire 6 and the insulating cable 8 by the insulating spacer 7 and the length l of the insulating cable 8.

[0016] In the illustrated example, by inserting the inductance L, but to stabilize the transformation ratio of the isolation transformer 10 by the series resonance to the capacitance C _2, it is also possible to configure by omitting the inductance L . The invention of claim 1 is
Since the insulated cable 8 is configured to share the voltage between the power transmission main line 2 and the overhead ground wire 6 according to the capacitance ratio, the ground voltage according to the floating capacitance of the insulated cable 8 to the ground is determined. It is taken out through the insulating transformer 10.

FIG. 5 is an explanatory diagram exaggerating a part of the embodiment according to the second aspect of the present invention. In the figure, 1 is a power transmission tower, 2 is a power transmission main line, and a support insulator 4
It is supported by. Reference numeral 5 denotes a connecting line sandwiched between the fixed points 3. An overhead ground wire 6 made of a conductive wire or OPGW is provided above the power transmission main line 2. An insulator 21 is supported by the power transmission tower 1 above the central portion of the connection line 5.
An intermediate electrode 22 made of a metal flat plate having a predetermined area is provided inside the insulator 21, and a lead-out cable 2 is provided at one end thereof.
3 is connected and pulled out of the insulator 21.

In the drawing, C ₁ is the capacitance between the power transmission main line 2 and the intermediate electrode 22, and C ₂ is the capacitance between the intermediate electrode 22 and the power transmission tower 1. FIG. 6 is a circuit diagram showing the electrical configuration of FIG. In the figure, a lead cable 23 is connected via an inductance L to one of the primary windings of the insulating transformer 10. Since the subsequent configuration is the same as that of FIG. 2, the same portions are denoted by the same reference numerals and description thereof will be omitted. Insulator 2
1 is a metal plate (intermediate electrode 2)
2) If it is integrally molded with an outdoor epoxy resin together with the drawer cable 23 and the fixing insert (not shown), manufacture and handling become easy.

Here, the capacitance C ₂ between the cylinder and the plane parallel conductor and the stored energy W according to the _second embodiment of the present invention are formed between the parallel cylinder conductors according to the first embodiment of the present invention. Since the principle is the same as that of capacitive coupling, detailed description is omitted. The necessary energy can be obtained by appropriately setting the parallel distance between the power transmission tower 1 and the intermediate electrode 22 in consideration of the area of the flat metal plate and the dielectric constant of the insulator used to form the insulator. According to the second aspect of the present invention, the voltage between the power transmission main line 2 and the power transmission tower 1 (ground plate) is configured such that the intermediate electrode 22 (metal plate) shares the voltage in accordance with the capacitance. The ground voltage corresponding to the ground capacitance of the intermediate electrode 22 is taken out through the insulating transformer 10.

The insulation transformer 10 is a so-called all-mold insulation transformer integrally coated with an insulating resin together with a primary winding, a secondary winding, an iron core, other terminals and mounting inserts. It is compact and easy to handle, and can be safely and easily mounted on power transmission towers at high altitudes. In addition, all-molded insulation transformers may be integrally coated with epoxy resin for outdoor use, or they are insulation transformers that pass low voltage. A metal spray such as a zinc metallikon treatment or a ceramic treatment may be applied to form an insulating transformer having excellent weather resistance.

Further, as shown in FIG. 2, the power supply control unit 11 is basically formed of an impedance adjustment circuit 12, a rectification circuit 13, and a smoothing capacitor 14, and is provided with a protection device such as a surge absorber as appropriate. It is also possible to adopt a configuration in which the container 10, the power supply control unit 11, the inductance L and the like are collectively stored in a metal box. Thus, there are the following advantages as compared with a power supply device mounted on a power transmission tower by the conventional electromagnetic induction method or electrostatic induction method.

(A) As long as the operating voltage is applied to the power transmission main line, a stable power supply can be always obtained regardless of weather conditions, day and night, or load fluctuations of the power transmission main line. (B) The insulated cable and the intermediate electrode of a metal flat plate are arbitrarily selected for their parallel length, spacing, and flat plate area, so that the capacitance can be set freely and the required electrostatic sharing voltage and, consequently, the required power supply capacity can be adjusted. Easy to get. (C) The work of disconnecting and connecting the exterior conductive part is not necessary for the overhead transmission line as well as the power transmission main line, so that the installation work at the transmission tower can be performed safely and easily.

(D) By providing a storage battery and a backup device as needed, it is possible to use the power supply for a monitoring device that is driven for a short period of time at regular intervals or a power supply for an aviation obstacle light at night. Furthermore, wireless communication using a public line between a tower installed in a mountainous remote place and the center side, or
If power is appropriately controlled by remote control that also serves as data transmission by optical communication using the OPGW, power can be efficiently used efficiently for driving the monitoring device for a short period of time and turning on the aviation obstacle lights at night.

[0024]

As described above, according to the present invention, a power supply device having a small load capacity can be installed in a power transmission facility in a mountainous remote place where either an overhead ground wire such as a conductive wire or an OPGW is laid. It is possible. In addition, since electrical energy induced by capacitive coupling with the power transmission main line is taken out of contact with the overhead ground wire, the equipment has a relatively simple configuration, and an efficient and low-cost power supply device can be obtained. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram exaggerating a part of an embodiment according to the first aspect of the present invention;

FIG. 2 is a circuit diagram showing an electrical configuration of FIG.

FIG. 3 is a perspective view showing an arrangement relationship between parallel conductors.

FIG. 4 is an arrangement diagram showing an arrangement relationship among an overhead ground wire, an intermediate electrode, and a power transmission main line.

FIG. 5 is an explanatory diagram showing a part of the embodiment according to the second aspect of the present invention in an exaggerated manner.

FIG. 6 is a circuit diagram showing an electrical configuration of FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power transmission tower 2 Power transmission main line 3 Fixed point 4 Support insulator connection 5 Connecting wire 6 Overhead ground wire 7 Insulation spacer 8 Insulation cable 9 Power supply unit 10 Insulation transformer 11 Power supply control unit 12 Impedance adjustment circuit 13 Rectification circuit 14 Smoothing capacitor 15 Load 21 insulator 22 intermediate electrode 23 lead cable

Claims (4)

[Claims] 1. A fixed length insulated cable suspended in parallel through a plurality of insulating spacers from an overhead ground wire made of a conductive wire or an OPGW, and a primary winding is connected between one end of the insulated cable and ground. And a power control unit connected to a secondary winding of the transformer. 2. A power transmission tower is disposed between the power transmission tower and the power transmission main line,
An intermediate electrode made of a metal plate covered with an insulator, a transformer having a primary winding connected between the intermediate electrode and ground, and a power supply control unit connected to a secondary winding of the transformer. A power supply device utilizing electrostatic induction, comprising: 3. The all-molded insulating transformer according to claim 1, wherein the primary winding, the secondary winding and the iron core of the transformer are integrally coated with an insulating resin. A power supply device utilizing electrostatic induction. 4. The electrostatic induction utilizing power supply device according to claim 1, wherein the power supply control section comprises an impedance adjusting circuit, a rectifier circuit and a smoothing capacitor.