KR101126291B1 - Current and voltage sensor mounted to a pole transformer - Google Patents

Abstract

The present invention discloses a columnar transformer-integrated current and voltage sensor which is integrally installed in the low pressure bushing of the columnar transformer and can be used for monitoring diagnosis of the columnar transformer, wherein the first inner ring and the first outer ring having different diameters are arranged concentrically. And a current transformer having a core of a coil winding, the current transformer having a core of a coil winding, casing on the first outer ring and marked with a (+) sign on the side wall of the columnar transformer. A first connecting portion having a central axis in contact with the first contact while passing through the first inner ring; A second low pressure bushing having a second inner ring and a second outer ring having a different diameter, and having a conductive second contact formed on an inner wall of the hole of the second inner ring, and marked (-) on the side wall of the columnar transformer. A second connecting portion in contact with the second contact while the central axis of the light penetrates through the second inner ring; And a current sensor unit connecting the first connection unit and the second connection unit, the current sensor unit sensing a current induced in the coil, and a voltage sensor unit sensing a voltage between the first contact point and the second contact point. And a casing connection.

Description

Current and voltage sensor with integrated pole transformer {Current and voltage sensor mounted to a pole transformer}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a columnar transformer integrated current and voltage sensor, and more particularly, to a columnar transformer integrated current and voltage sensor which is integrally installed in a low voltage bushing of a columnar transformer and can measure current and voltage on a load side.

The monitoring and diagnosis method of the existing pole-type transformer for power distribution includes observing the distribution transformer through the five senses of the instantaneous distribution line of the distribution line, or determining the abnormality of the distribution transformer by using various diagnostic equipment such as a thermal imaging camera or a high frequency diagnosis device. Offline way of doing this.

Recently, the preventive diagnosis method for columnar transformers has been considered to introduce an on-line monitoring diagnosis system that combines power technology and IT technology by evading the conventional off-line method described above, and measures information such as current, voltage, and load ratio of the columnar transformer. After that, a system for transmitting it to a remote management server through wired / wireless communication has been developed and is currently in operation.

  However, in order to construct the columnar transformer monitoring diagnosis system, a current and voltage sensor for acquiring the load information of the transformer must be separately installed on the secondary side of the transformer, and as a result, it is difficult to install the site and follow-up management. Brings about.

In addition, since the current and voltage sensor and the sensor connection wires are exposed to the outside of the pole, it may cause a mishap between other distribution lines or communication lines on the pole, and may have problems such as impairing the appearance of the city.

The present invention for solving the above problems by installing the current and voltage sensor integrally to the column transformer, solve the trouble of installing a separate current and voltage sensor for building the column transformer monitoring diagnosis system, and at the same time, And a columnar transformer-integrated current and voltage sensor having an aesthetic effect.

In the columnar transformer integrated current and voltage sensor according to the present invention, the first inner ring and the first outer ring having different diameters are arranged concentrically, and a conductive first contact is formed on the inner wall of the hole of the first inner ring, and the coil A current transformer having a core of windings is cased in the first outer ring and the central axis of the low pressure bushing (hereinafter referred to as the first low pressure bushing) on the side marked (+) on the side wall of the columnar transformer penetrates the first inner ring. A first contact portion in contact with the first contact; The second inner ring and the second outer ring having different diameters are arranged concentrically, and a conductive second contact is formed on the inner wall of the hole of the second inner ring, and the low pressure bushing on the side of the columnar transformer marked with (-) ( A second connecting portion contacting the second contact while the central axis of the second low pressure bushing penetrates through the second inner ring; And a current sensor unit connecting the first connection unit and the second connection unit, the current sensor unit sensing a current induced in the coil, and a voltage sensor unit sensing a voltage between the first contact point and the second contact point. And a casing connection.

Here, the first connecting portion may be provided between the packing of the first low pressure bushing and the outer wall of the columnar transformer, and the second connecting portion may be installed between the packing of the second low pressure bushing and the outer wall of the columnar transformer. Can be.

The current sensor unit may include: a current transformer configured to generate an organic current from a current in which the core is wound around the coil and flows in a central axis of the first low pressure bushing according to a winding ratio; A first varistor element connected between both ends of the coil and absorbing a surge; And a resistor connected in parallel with the first varistor element.

The voltage sensor unit includes a second varistor element connected between the first contact contacting the center axis of the first low pressure bushing and the second contact contacting the center axis of the second low pressure bushing and absorbing a surge. And a transformer capable of modifying an AC voltage applied to both ends of the second varistor element and physically insulating the columnar transformer and the voltage sensor unit.

Since the column and transformer integrated current and voltage sensor according to the present invention is installed integrally with the column transformer, it is unnecessary to install a separate current and voltage sensor for building the column transformer transformer diagnosis system. This has the effect of providing an advantage.

1 is a schematic diagram showing the configuration of a columnar transformer integrated current and voltage sensor according to the present invention.
2 is a circuit diagram of the internal circuit of FIG.
3 is a diagram illustrating that the current and voltage sensors according to the present invention are integrally installed in the columnar transformer.
4 is an assembly view of the low pressure bushing.
5 is an exploded view of a low pressure bushing.

The columnar transformer integrated current and voltage sensor according to the present invention may be implemented as shown in FIG. 1, and is integrally installed between both ends of the columnar transformer first low pressure bushing and the second low pressure bushing.

Columnar transformers are transformers installed on poles to lower the extra-high voltage of AC distribution lines to low voltage. The columnar transformer has a special high pressure bushing installed to inject a special high pressure from an AC distribution line, and a low pressure bushing installed to supply electric power lowered to a low pressure therein. The columnar transformer integrated current and voltage sensor according to the present invention provides an embodiment in which the low voltage bushings are integrally installed.

First, referring to FIG. 1, a columnar transformer integrated current and voltage sensor according to the present invention includes a first connection part 10 coupled to a first low pressure bushing, a second connection part coupled to a second low pressure bushing, and a first connection part 10. ) And the second connection part 20, and a connection part 30 in which an internal circuit is casing.

Here, the first connecting portion 10 is disposed so that the first inner ring 11 and the first outer ring 12 having different diameters are concentric, and the conductive first contact points are formed on the inner wall of the hole of the first inner ring 11. 13 is formed, a current transformer (corresponding to T1 in FIG. 2) in which the core 14 is wound into the coil 15 is cased in the first outer ring 12 and the central axis 16 of the first low pressure bushing is formed. ) Is in contact with the first contact 13 while passing through the first inner ring 11.

In addition, the second connecting portion 20 is disposed so that the second inner ring 21 and the second outer ring 22 having different diameters are concentric, and the conductive second contact point is formed on the inner wall of the hole of the second inner ring 21. 23 is formed and is installed on the side wall of the columnar transformer so that the central axis 26 of the second low pressure bushing is in contact with the second contact 23 while passing through the second inner ring 21.

The first connection part 10 and the second connection part 20 described above are connected by the connection part 30, and the connection part 30 has a configuration in which the internal circuit 32 is incorporated. The internal circuit 32 has contacts A and B connected to both ends of the coil 15 of the first connecting portion 10 and has a contact C connected to the first contact 13 of the first connecting portion 10. , The contact D is connected to the second contact 23 of the second connecting portion 20. Here, the contacts A and B of the internal circuit 32 are contacts for sensing current, and the contacts C and D are contacts for sensing voltage. The internal circuit 32 has terminals CT1 and CT2 for outputting a result of sensing current and terminals PT1 and PT2 for outputting a result of sensing voltage.

The internal circuit 32 of the connection unit 30 described above has a wiring structure as shown in FIG. 2.

Referring to FIG. 2, the internal circuit 32 includes a current sensor unit 34 and a voltage sensor unit 36.

The current sensor unit 34 includes a current transformer T1 in which a coil 15 is formed in the core 14 to sense current flowing from the terminal corresponding to the central axis 16 of the first low pressure bushing 40 to the load. A varistor element Rv1 connected between both ends of the coil 15, that is, the contacts A and B, and absorbing the surge, and a resistor R1 connected in parallel with the varistor element Rv1. Here, the current transformer T1 may have a current ratio determined according to the turns ratio, the resistor R1 is a sharing resistor for converting the current into a voltage, and both ends of the resistor R1 output the result of sensing the current. Are connected to terminals CT1 and CT2.

The output of the current sensor unit 34 is determined by the voltages at both ends of the terminals CT1 and CT2, and the current ratio of the current transformer T1 is N: 1, and the output current of the columnar transformer, that is, the central axis of the first low pressure bushing 40 ( When the current flowing through 16) is i (t) [A], Equation 1 below may be established.

&Quot; (1) "

vc (t) = 1 / N * R1 * i (t) [V]

Here, vc (t) is a voltage applied to the resistor R1, that is, the output voltage of the current sensor unit 34. The resistor R1 is a device for converting the current sensed by the current sensor unit 34 into a voltage and can be removed if necessary according to the method of use of the current sensor, and the current sensor unit 34 when the resistor R1 is removed. The output can be obtained in the form of current value. In this case, the output of the current sensor can be calculated as shown in Equation 2 below.

<Equation 2>

ic (t) = 1 / N * i (t) [A]

Here, ic (t) is a current value output from the current sensor unit 34 in the state where the resistor R1 is removed.

Meanwhile, the voltage sensor unit 36 includes a first contact 13 (corresponding to the contact point C of FIGS. 1 and 2) and a second low pressure bushing contacting the central axis 16 of the first low pressure bushing 40. The varistor element Rv2 connected between the second contact 23 (corresponding to the contact point D of FIGS. 1 and 2) in contact with the central axis 26 of the 50 and absorbing the surge, A transformer T2 for inducing and outputting a current flowing in the primary side connected in parallel with the varistor element Vr2 to the secondary side according to the turns ratio.

The output of the voltage sensor unit 36 is determined by the voltage applied across the terminal PT1 and the terminal PT2. The primary and secondary winding ratios of the transformer T2 are M1: M2 and the output voltage of the column transformer is v (t) [ V], the following Equation 3 can be established. The output voltage of the columnar transformer corresponds to a potential difference between the central axis 16 of the first low pressure bushing 40 and the central axis 26 of the second low pressure bushing 50.

&Quot; (3) &quot;

vp (t) = M2 / M1 * v (t) [V]

Vp (t) is the output voltage of the voltage sensor unit 36.

The transformer T2 configured in the above-described voltage sensor unit 36 may be used to physically insulate the voltage sensor unit 36 from the transformer side, and the voltage sensor unit 36 may be used in accordance with a method of use. By removing T2), the secondary voltage of the transformer can be directly connected to the output of the voltage sensor.

The preferred embodiment of the columnar transformer integrated current and voltage sensor according to the present invention configured as shown in Figures 1 and 2 can be combined with the columnar transformer as shown in FIG.

3, the low pressure bushings 40 and 50 are installed on the side wall 60 of the columnar transformer, and the first low pressure bushing 40 has a central axis 16 of the terminal specified as (+) on the side wall of the columnar transformer. The second low pressure bushing 50 has a central axis 26 of the terminal specified by the negative (-) on the columnar transformer side wall.

Looking at the first low pressure bushing (40), the inner insulator 42 is installed with the packing 41 for waterproofing inside the side wall 60 of the columnar transformer, the inner insulator 42 is the central axis (16) Is penetrated and installed to extend to the outside of the columnar transformer, the bolt 45 is screwed to the end of the central shaft 16, the inner insulator 42 having a ceramic material between the inner insulator 42 and the bolt 45 The buffer washer 43 for preventing physical damage of the c) and the metal washer 44 for supporting the engagement state are installed. Then, the first connecting portion 10 is provided between the packing 46 and the side wall for waterproofing to the outside of the side wall 60 of the columnar transformer, the outer insulator 47 is provided to the outside of the packing 46, the outside This constitutes a head 48 which is an extended end of the central axis 16.

The above-described first low pressure bushing 40 may be configured as shown in FIGS. 4 and 5, and the head 48 has a coupling structure that can be easily connected to the load. Since the structure of the second low pressure bushing 50 in which the second connecting portion 20 is installed while being adjacent to the first low pressure bushing 40 is also the same as that of the first low pressure bushing 40, redundant description thereof will be omitted. The connecting portion 30 between the connecting portion 10 and the second connecting portion 20 may be configured to be in close contact with the outer side wall 60 of the columnar transformer.

By configuring as described above, the columnar transformer integrated current and voltage sensor according to the present invention can build a columnar transformer monitoring diagnostic system without the need to install a separate current and voltage sensor.

In addition, since the current and voltage sensors are integrally formed with the columnar transformer, management and aesthetic benefits can be achieved.

10: first connection portion 11, 21: inner ring
12, 22: outer ring 13: first contact
14 core 15 coil
16, 26: central axis 20: second connection portion
23: second contact point 30: connection part
32: internal circuit 34: current sensor
36: voltage sensor unit 40, 50: low pressure bushing
41, 46: packing 42: inner insulator
47: outer insulator 43: buffer washer
44: metal washer 45: bolt
48: head

Claims (5)

The first inner ring and the first outer ring having different diameters are arranged to be concentric, a conductive first contact is formed on the inner wall of the hole of the first inner ring, and a current transformer having a core of a coil winding is used for the first outer ring. A first connecting portion casing in contact with the first contact while the central axis of the low pressure bushing (first low pressure bushing) on the side of the columnar transformer is marked (+) through the first inner ring;
The second inner ring and the second outer ring having different diameters are arranged concentrically, and a conductive second contact is formed on the inner wall of the hole of the second inner ring, and the low pressure bushing on the side of the columnar transformer marked with (-) ( A second connecting portion in contact with the second contact while the central axis of the second low pressure bushing passes through the second inner ring; And
A casing therein is connected between the first connection part and the second connection part and includes a current sensor part sensing a current induced in the coil and a voltage sensor part sensing a voltage between the first contact point and the second contact point. Columnar transformer integrated current and voltage sensor, characterized in that it comprises a connection.
The method of claim 1,
The first connection portion is a columnar transformer integrated current and voltage sensor is provided between the packing of the first low-voltage bushing and the outer wall of the columnar transformer.
The method of claim 1,
And said second connecting portion is provided between the packing of said second low voltage bushing and the outer wall of said columnar transformer.
The method of claim 1, wherein the current sensor unit,
A current transformer for winding the core to the coil and generating an induced current from a current flowing in a central axis of the first low pressure bushing according to a turns ratio;
A first varistor element connected between both ends of the coil and absorbing a surge; And
And a resistor connected in parallel with the first varistor element.
The method of claim 1, wherein the voltage sensor unit,
A second varistor element connected between the first contact contacting the center axis of the first low pressure bushing and the second contact contacting the center axis of the second low pressure bushing and absorbing a surge; And
And a transformer for modifying an alternating voltage applied to both ends of the second varistor element and physically insulating the columnar transformer and the voltage sensor unit.

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