JP2696614B2 - Electricity detector for electrical equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power detection device, and more particularly to a power detection device for electric equipment in which a leading end of a lead-in bushing is disposed in a case.

[0002]

2. Description of the Related Art In recent years, with the diversification of power demand, stable power supply has become necessary, and it is desired to obtain accurate information on current and voltage flowing in a distribution line for automatic disconnection of a faulty section. . For this reason, it is desirable to obtain information safely and with high accuracy even in the detection and measurement of voltage and current.In the case of conventional electric equipment, an instrument transformer or current transformer is required to measure the current or voltage of a line. The built-in one is used.

[0003]

However, in a conventional power detector of a segmented switch, for example, an instrument transformer and a current transformer are separately arranged, or these components are individually mounted. Therefore, there is a problem that not only the structure is complicated but also the mounting operation is very troublesome.

[0004] The present invention has been made in view of the problems existing in such prior art, and an object of the present invention is to integrate a transformer and a current transformer and unitize them. A voltage detector having a simple structure and easy installation.

[0005]

In order to achieve the above object, according to the present invention, an inner side wall and an outer side wall stand around a retractable bushing in a unit case which is attached to the case by inserting a retractable bushing. A core for measuring current, a first electrode plate for measuring voltage between the inner side wall and the core, and an outer wall formed in an annular storage groove formed between the inner side wall and the outer side wall. A second electrode plate for voltage measurement is housed between the core and the core .

[0006]

According to the present invention, the retractable bushing is inserted into and fixed to the case, and the unit case is attached to the case with the retractable bushing inserted. The hollow part provided in the unit case is fitted into the pull-in bushing and attached to the case. In addition, the core is housed in a housing groove formed between the inner wall and the outer wall which are provided upright, so that the magnetic field due to the line current can be measured. The first electrode plate on the power application side and the second electrode plate on the ground side are housed in this housing groove, and the line voltage can be measured. For this reason,
The core for current measurement and the first and second electrodes for voltage measurement are compactly mounted in the storage groove, so that the transformer and the current transformer can be integrated. Further, it is possible to assemble the electric device simply by attaching the unit case to the case.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a section switch for gas filling of a distribution line will be described in detail below.

As shown in FIG. 1, three inlets 2 and 3 are provided on the left and right sides of the case 1 respectively (only one is shown in FIG. 1). The connected lead-in bushings 4 and 5 are inserted and fixed in the respective lead-in ports 2 and 3 to form an airtight container. Sulfur hexafluoride gas is sealed inside the switch to ensure insulation. In addition, rod-shaped terminals 6,
7 is protruded and fixed, and the front end portion thereof is disposed to face.
A cylindrical movable block 8 is movably fitted into the left terminal 7, and a drive shaft 10 is rotated by operating an operation lever 9 provided outside the case 1, whereby the drive lever 11 is turned. The movable block 8 can be moved to the right terminal 6 side. And this movable block 8
Inside the contact 12 is made contactable with the right terminal 6.
By rotating the drive shaft 10, the movable block 8 can open or close the distribution line by connecting or separating the terminals 6 and 7 from each other.

In FIG. 1, a power detection device 13 for detecting each phase is mounted inside a case 1 having a right-side entrance 2 formed therein, while a zero-phase detection is provided in a case 1 having a left-side entrance 3 formed therein. Are installed.

On the back surface of the case 1, a suspension mounting plate 15 for mounting to a support arm of a utility pole is attached, and can be suspended and fixed to the utility pole. As shown in FIG. 2, a thick seat plate 1 is provided around the two inlets 2 and 3 of the case 1.
6 are laminated and joined by welding.

The retractable bushing 4 is made of a substantially cylindrical porcelain having a fold at its peripheral edge. The leading end has a small diameter so that it can be inserted into the case 1, and the middle part presses the gasket 17 to the seat plate 16. It abuts hermetically. A mounting bracket 18 that holds the peripheral edge of the retraction bushing 4 is fixed to the seat plate 16 by mounting screws 19. A cushion member 20 is provided at a position where the mounting bracket 18 comes into contact with the porcelain portion of the retractable bushing 4. A center conductor 21 having one end as a terminal (not shown) for connecting to an electric wire and the other end as a terminal 6 is fixedly inserted through the center of the shaft of the lead-in bushing 4. Further, the case 1 is provided with a pressure release port 22a which is closed by a pressure release lid 22. The discharge port 22a is opened when a discharge arc is generated due to a short-circuit current so as to discharge the arc gas in the case 1. .

As shown in FIGS. 3 and 4, the power detector 13 for detecting each phase has a unit case 23 in which a core 24, a first electrode plate 25, and a second electrode plate 26 are housed. The unit case 23 is formed in a thin cylindrical shape, and a hollow portion 27 into which the retraction bushing 4 is inserted is formed by an inner wall 28. An outer wall 29 is provided concentrically outside the inner wall 28, and an annular storage groove 30 for storing the core 24 is formed between the inner wall 28 and the outer wall 29. On the left side of the outer wall 29, the storage groove 30 is extended downward and the storage groove 30 is opened, and on the right side thereof, a bottom plate 31 is provided so as to extend downward and be continuous with the bottom of the storage groove 30. I have.

The magnetic core 2 housed in the housing groove 30
Numeral 4 has a rectangular cross section, and is formed in an annular shape with a gap 32 provided at a lower portion thereof. This core 24
Are stored at the bottom of the storage groove 30 (see FIG. 5). A head having a built-in detection unit (not shown) of the magnetic field sensor head 33 is arranged in the gap 32, and is screwed to the bottom plate 31 by a clamp 34. The magnetic field sensor head 33 is configured to convert a magnetic field caused by a current flowing through the center conductor 21 into an optical signal proportional to the strength. The signal detected by the magnetic field sensor head 33 can be transmitted to a measuring unit (not shown) via an optical fiber 35 via a connector 36 attached to the bottom of the case 1. As described above, the core 24 is disposed concentrically with the center conductor 21 disposed at the axial center of the pull-in bushing 4, and the head of the magnetic field sensor head 33 is connected to the core 24.
, The magnetic field sensor head 33 can be accommodated in a small accommodation space, and the current can be accurately detected. In addition, the other-phase center conductor 2
The configuration is such that an accurate line current signal can be obtained without any influence such as noise generation due to the influence of the magnetic field.

A first electrode plate 25 made of a band-shaped thin plate is disposed in a loop shape along the inner wall 28 in the storage groove 30 in which the core 24 is housed, and also a band-shaped thin plate along the outer wall 29. The second electrode plate 26 is formed in a loop shape. Therefore, the first electrode plate 25 and the second electrode plate 26 are opposed to each other with a gap defined by the inner wall 28 and the outer wall 29, and the voltage applied to the center conductor 21 is divided. It is possible. A voltage sensor head 37 and a capacitor 38 for capacitance correction are attached to the bottom plate portion 31 by screws (not shown) in parallel. The connection terminal 39 of the first electrode plate 25 extends in the direction of the bottom plate portion 31 and is connected to the voltage sensor head 37 via one end of a capacitor 38 by a lead wire 40. Further, a lead wire 41 connected to one end of the second electrode plate 26 is connected to the voltage sensor head 37 via the other end of the capacitor 38. The voltage sensor head 37 is the first electrode plate 2
The Pockels element converts the line voltage divided by the capacitance formed between the first electrode plate 5 and the second electrode plate 26 into an optical signal. This optical signal is supplied to a connector 3 attached to the bottom of the case 1 by an optical fiber 42.
6, and can be transmitted to a measuring unit (not shown).
The accommodating groove 30 is filled with the rubber mold 43 in a state where the core 24, the magnetic field sensor head 33, the electrode plates 25 and 26, and the voltage sensor head 37 are disposed as described above, and the opening is closed. Have been.

A mounting flange 44 is provided on the outer edge of the unit case 23, and the unit case 23 is mounted on the case 1 by screws 45. In FIG. 1, a current transformer for detecting a zero-phase current is attached to the lid 5 on the left side of the case 1 so that a ground fault can be detected.

Next, the operation of the above-described power detection device of this embodiment will be described.

First, in order to attach the lead-in bushing 4 to the lead-in port 2 of the gas switch, the terminal 6 side of the lead-in bushing 4 is inserted from outside the lead-in port 2. Then, the mounting bracket 18 is fastened and fixed to the seat plate 16 with the mounting screw 19. As a result, the retractable bushing 4 is accurately attached to a predetermined portion and is air-tightly connected to the gasket 17 disposed on the seat plate 16. Next, the unit case 23 is inserted through the open pressure release port 22 a, and a screw 45 is screwed into a mounting flange 44 of the unit case 23 to be fixedly mounted inside the case 1. For this reason, the power detection device 13 housed in the unit case 23 can be easily and accurately set on the predetermined lead-in bushing 4.

In the voltage detecting device 13 of this embodiment, the core 24 is accommodated in the accommodating groove 30 of the unit case 23, and the magnetic field sensor head is provided in the gap 32 formed by cutting out the lower part of the core 24. Since the 33 detection units are arranged, the influence of the other phases of the three-phase electric line is not affected by the magnetic field sensor head 3.
3 does not appear. In addition, since the current signal is converted into an optical signal in the magnetic field sensor head 33, there is no generation of noise due to other phases as in the case of connection with a normal lead wire, and the current transformer has a high SN ratio. Can be. Further, since the magnetic field sensor head 33 is accommodated in the gap 32 of the core 24, a large accommodation space for the magnetic field sensor head 33 is not required.

Further, the first electrode plate 25 and the second electrode plate 26
Are provided along the inner wall 28 and the outer wall 29, respectively.
Since the first electrode plate 25 and the second electrode plate 26 are housed and arranged, the interval between the first electrode plate 25 and the second electrode plate 26 can be set accurately, and an accurate voltage can be detected. In particular, since the inside of the accommodation groove 30 is fixed by the rubber mold 43, the core 24 and the first and second electrode plates 25 and 26 are not deviated and have excellent long-term reliability. Also,
Since the first electrode plate 25 and the second electrode plate 26 are arranged using the inside of the accommodation groove 30 accommodating the core 24, no special storage space for arranging them is required. In addition, the capacitor 38 for capacitance correction and the voltage sensor head 37 are integrally mounted on the bottom plate 31, and the optical signal from the voltage sensor head 37 does not generate noise due to the surrounding electric field or magnetic field due to rainfall. Can be accurately detected. Further, by using a Pockels element having a large input impedance as the voltage sensor head 37, it is not necessary to apply impedance to the detection system, and stable measurement can be performed up to a high frequency band.

As described above, in this embodiment, since all the members required as the power detector are integrally mounted on the unit case 23, the screws 4 are attached to the mounting flange 44.
5 can be attached to the gas switch just by fixing, and the power detection device can be made more compact.

In this embodiment, the magnetic field sensor head 3
3 and the voltage sensor head 37 have a built-in optical element for converting an electric signal into an optical signal, and the optical element is transmitted to the measuring unit by an optical signal. Accurate measurement can be performed without receiving external guidance.

The present invention is not limited to the above-described embodiment, and can be embodied by arbitrarily changing the configuration of each unit without departing from the present invention. For example,
Although the example in which the storage groove 30 is constituted by the continuous inner side wall 28 and outer side wall 29 is shown, the core 24, the first electrode plate 25 or the second electrode plate is not necessarily required to be continuous but may be an intermittent wall. It is only necessary that 26 can be locked.

[0023]

According to the present invention, an inner wall and an outer wall are provided concentrically on the outside of a hollow portion to form a storage groove, and a current measurement core and a voltage measurement first electrode are provided in the storage groove. Plate and second
Since the transformer and the current transformer are housed together with the electrode plate to be integrated and unitized, it is possible to provide a compact and easy-to-install power detection device having a simple structure.

[Brief description of the drawings]

FIG. 1 is a sectional view of a switch.

FIG. 2 is a cross-sectional view showing a mounting state of the power detection device.

FIG. 3 is a side view of the power detection device.

FIG. 4 is an exploded perspective view of the power detection device.

FIG. 5 is a cross-sectional view of the power detection device.

[Description of Signs] 1 ... Case 4 ... Retraction bushing 5 ... Retraction bushing 23 ... Unit case 24 ... Core 25 ... First electrode plate 26 ... Second electrode plate 27 ... Hollow part 28 ... Inner wall 29 ... Outer wall 30 ... Storage groove

Claims (1)

(57) [Claims] 1. A power detection device for an electric device in which a leading end of a lead-in bushing is disposed in a case, wherein a unit case in which the lead-in bushing is inserted and attached to the case is provided around the lead-in bushing. An inner wall and an outer wall are erected, and a current measuring core is provided in an annular storage groove formed between the inner wall and the outer wall;
A first electrode plate for measuring voltage between the inner wall and the core ;
A voltage detecting device for electrical equipment, wherein a second electrode plate for measuring voltage is housed between the outer wall and the core .