CN202307503U - Electronic current and voltage combined transformer with high-voltage support pillar type suspension structure - Google Patents

Abstract

The utility model relates to an electronic current-voltage combination transformer with a high-voltage pillar type suspension structure. A metal electrode is arranged between the inner and outer cylinders of the voltage equalizing shielding cylinder, and a metal electrode is arranged between the inner cylinder or the outer cylinder of the voltage equalizing shielding cylinder. Insulation medium layer; coaxial capacitor electronic voltage transformer includes equivalent series high-voltage capacitor and low-voltage capacitor; primary conductor, protective shell and voltage equalizing shielding cylinder and SF6 insulating gas between them as the insulating medium to form the high-voltage Capacitor: the metal electrode, the voltage equalizing shielding cylinder, and the low-voltage capacitor composed of the insulating medium layer as the insulating medium, and the two ends of the low-voltage capacitor are connected to the voltage signal acquisition unit in the base. The utility model has simple structure, high insulation strength, simultaneous detection of current and voltage, compact structure, high precision and reliable performance, and is designed on the basis of the original transformer, greatly reducing the cost.

Description

An electronic current-voltage combination transformer with a high-voltage pillar suspension structure

technical field

The utility model relates to a novel high-voltage pillar-type suspension structure electronic current-voltage combined transformer.

Background technique

With the development of the power system towards large capacity, ultra-high voltage and ultra-high voltage, the requirements for miniaturization, intelligence and high reliability of power equipment are getting higher and higher. Conventional electromagnetic voltage transformer or capacitive voltage transformer has complex insulation structure, increased volume, high cost, cumbersome wiring, large use space, complicated operation during installation, prone to oversaturation, remanence, magnetic saturation, and ferromagnetic resonance , small dynamic range and other shortcomings, it has been difficult to meet the application development requirements of the power system. Therefore, electronic current and voltage transformers are mostly used to provide conventional transformers.

Electronic current transformers use Rogowski coils, low-power coils or magneto-optical transformers. The collected signal is reversed, integrated, and amplified by the internal circuit of the collector, photoelectrically converted into an optical signal, connected to the merging unit through an optical fiber, and finally sent to the measurement and protection equipment.

Electronic voltage transformer is a voltage transformer formed by the principle of coaxial capacitor series voltage division. Chinese patent document 200710169091.1 is a new high-voltage combined independent electronic current and voltage transformer. This patent document discloses the basic structure and principle of the electronic voltage transformer, which will not be repeated here. It should be pointed out that in the structure of the electronic voltage transformer disclosed in this patent document, the coaxial capacitors are arranged in the primary conductor room where the primary conductor is located, the electrodes are arranged inside the shielding cylinder, and the high and low voltage capacitors are all based on the primary conductor. Axis, this way is easy to cause breakdown when the insulation performance drops.

Utility model content

The purpose of this utility model is to provide a new high-voltage pillar-type suspension structure electronic current-voltage combination transformer, which realizes the electronic current-voltage combination transformer on the basis of the structure of the traditional pillar-type SF6 gas-insulated transformer.

In order to achieve the above purpose, the solution of this utility model is: a high-voltage pillar-type suspension structure electronic current-voltage combination transformer, including a protective shell on the top, an insulating sleeve on the bottom for fixing on the base, and a protective shell The bottom opening of the body and the top opening of the insulating sleeve are set correspondingly. The protective shell and the insulating sleeve are fixedly connected through a pot insulator. A support tube is provided between the closing end of the pot insulator and the base. A voltage-equalizing shielding cylinder is fixed for passing through the primary conductor, and the voltage-equalizing shielding cylinder is divided into an inner cylinder and an outer cylinder; the protective shell and the insulating sleeve are filled with SF6 insulating gas; the combined transformer includes an electronic current Transformer and coaxial capacitor electronic voltage transformer, the coil of the electronic current transformer is arranged between the inner cylinder and the outer cylinder of the pressure equalizing shielding cylinder, and the coil passes through the secondary signal arranged in the support tube The wire is connected to the current signal acquisition unit in the base; a metal electrode is provided between the inner and outer cylinders of the voltage equalization shielding cylinder, and an insulating medium layer is provided between the metal electrode and the inner cylinder or outer cylinder of the voltage equalization shielding cylinder; The coaxial capacitive electronic voltage transformer includes an equivalent series connected high-voltage capacitor and a low-voltage capacitor; the primary conductor, the protective casing, the voltage-equalizing shielding cylinder and the SF6 insulating gas between them form the high-voltage capacitor; The metal electrode, the voltage equalizing shielding cylinder and the insulating medium layer are used as the insulating medium to form the low-voltage capacitor, and both ends of the low-voltage capacitor are connected to the voltage signal acquisition unit in the base.

The metal electrode is arranged on the inner wall of the outer cylinder of the voltage equalizing shielding cylinder, and an insulating medium layer is arranged between the metal electrode and the inner wall of the outer cylinder. The metal electrode is arranged on the outer wall of the inner cylinder of the voltage equalizing shielding cylinder, and an insulating medium layer is arranged between the metal electrode and the outer wall of the inner cylinder. The metal electrode is grounded. A resistance-capacitance divider resistor is connected in parallel between the input terminals of the voltage signal acquisition unit. The coil of the electronic current transformer is a Rogowski coil.

The utility model arranges the low-voltage capacitor on the inner (outer) side wall of the outer cylinder (inner cylinder) of the voltage equalizing shielding cylinder where the electronic current transformer is installed. Compared with the inside of the inner cylinder in the above-mentioned patent documents, the structure is more concise , The dielectric strength is provided, and the simultaneous detection of current and voltage is realized. The structure is compact, the precision is high, and the performance is reliable. The design is based on the original transformer, which greatly reduces the cost.

Description of drawings

Fig. 1 is the structural representation of the combined transformer of the present utility model;

Fig. 2 is a schematic diagram of a voltage transformer of the present utility model;

Fig. 3 is an equivalent circuit diagram of a voltage transformer of the present invention.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described in further detail.

As shown in Figure 1, Figure 2, and Figure 3, a new type of high-voltage pillar-type suspension structure electronic current-voltage combined transformer is based on a pillar-type gas-insulated transformer, including a protective shell 4 on the top, and a protective shell 4 on the bottom for fixing On the insulating sleeve 11 on the base 23, the bottom opening of the protective shell 4 is arranged correspondingly to the top opening of the insulating sleeve 11, and the protective shell and the insulating sleeve are fixedly connected by a pot insulator 7, and the closing end of the pot insulator 7 A support tube 20 is provided between one side and the base, and a voltage equalizing shielding cylinder for piercing the primary conductor is fixed on the other side. The voltage equalizing shielding cylinder is divided into an inner cylinder 6 and an outer cylinder 5; the protective shell 4 and the insulating The bushing 11 is filled with SF6 insulating gas; the combined transformer includes an electronic current transformer and a coaxial capacitor electronic voltage transformer, and the coil 1 of the electronic current transformer is arranged on the inner cylinder 6 and the outer cylinder of the voltage equalizing shielding cylinder 5, its coil 1 is connected to the current signal acquisition unit in the base 23 through the high temperature shielded wire 10 set in the support tube 20.

The improvement of the present utility model is that a metal electrode 13 is arranged between the inner and outer cylinders of the voltage equalizing shielding cylinder. An insulating medium layer 12 is provided between the inner walls of the cylinder 5 . As another embodiment, the metal electrode 13 can also be arranged on the outer wall of the inner cylinder 6 of the voltage equalizing shielding cylinder, and an insulating medium layer 12 (epoxy material or directly double-sided coating) is provided between the metal electrode 13 and the outer wall of the inner cylinder. Copper plate, as shown in Figure 2, the utility model adopts double-sided copper-clad laminates to roll into a cylindrical shape, leaving a gap in the middle to prevent the two sides of the copper-clad laminates from being connected to form a short circuit). Metal electrode 13 is grounded.

As shown in Figure 1, the coaxial capacitive electronic voltage transformer includes an equivalent series connected high-voltage capacitor C1 and low-voltage capacitor C2; a primary conductor 2, a protective shell 4, an outer cylinder 5 of the equalizing shielding cylinder, and SF6 insulating gas between them The high-voltage capacitor C1 is composed of an insulating medium; the metal electrode 13, the outer cylinder 5 of the equalizing shielding cylinder and the low-voltage capacitor C2 are composed of the insulating medium layer 12 as an insulating medium, and the two ends of the low-voltage capacitor C2 are connected to the base 23. Voltage signal acquisition unit 18. A small resistor R is connected in parallel to the input terminal 17 of the voltage signal acquisition unit 18 to ensure the accuracy of the voltage signal transmission.

The inner and outer cylinders 5, 6 of the voltage equalizing shield are insulated and fixed by basin insulators 7 (as other implementations, support insulators and insulating rods can also be used), and the inner and outer cylinders 5, 6 of the equalizing shield are at floating potential. The pot insulator 7 is fixed on the insulating bushing 11 through the flange 8, the insulating bushing 11 is fixed on the base 23, and the gas density meter 22 is installed outside the base 23, and the 21 is an air-filling hole. In the current transformer, the Rogowski coil (low-power iron core coil) 1 is built in the suspension structure composed of the voltage equalization shielding outer cylinder 5 and the inner cylinder 6, and the lead wire 9 of the Rogowski coil 1 adopts a high-temperature resistant shielding wire to pass through the lead wire shielding tube 20 to the current transformer. The input terminal 15 of the signal acquisition unit 16 and the output line of the voltage transformer are connected to the voltage signal acquisition unit 18 , and the two acquisition units are installed in the base 23 to output digital signals through the optical fiber 19 . The acquisition units 16 and 18 are installed inside the base 23 to improve the working environment of the electronic circuit and reduce electromagnetic interference. The local power supply 14 supplies power to the acquisition units, which overcomes the problems of active transformers and provides stable power supply. The metal electrodes at both ends of the output of the low-voltage capacitor and the two ends of the shielding cylinder of the equalizing ring are connected in parallel with a large resistor 24 to form a high-voltage suppression circuit to suppress transmission of overvoltage.

Claims (6)

1. high-voltage strut formula suspension structure electronic current combination of voltages instrument transformer; The protection housing that comprises the top; The bottom, be used for fixing the insulating sleeve on base; The corresponding setting of bottom opening of protection housing with the insulating sleeve open top, the protection housing is fixedly connected through a disc insulator with insulating sleeve, and the closing in of said disc insulator is held between a side and the base and is provided with stay pipe; Opposite side is fixed with all pressures shielding cylinder that is used to be located on the Primary Conductor, all presses shielding cylinder to be divided into inner core and urceolus; Be filled with the SF6 insulating gas in said protection housing and the insulating sleeve; Combination transformer comprises electronic current mutual inductor and coaxial capacitance electronic type voltage transformer; The coil of electronic current mutual inductor is arranged between the said inner core and urceolus of all pressing shielding cylinder, and its coil is connected to the current signal collecting unit in the base through the secondary singal line that is arranged in the said stay pipe;

It is characterized in that, be provided with metal electrode between the said inner/outer tube of all pressing shielding cylinder, metal electrode and all press between inner core or the urceolus of shielding cylinder and be provided with insulating medium layer;

Said coaxial capacitance electronic type voltage transformer comprises the high-voltage capacitance and the low-voltage capacitance of equivalent series; Said Primary Conductor, protection housing are that dielectric is formed said high-voltage capacitance with all pressing shielding cylinder to reach with the SF6 insulating gas between them; Metal electrode, all press shielding cylinder and be that dielectric is formed said low-voltage capacitance with said insulating medium layer, the low-voltage capacitance two ends are connected to the voltage signal acquisition unit in the base.

2. a kind of high-voltage strut formula suspension structure electronic current combination of voltages instrument transformer according to claim 1; It is characterized in that; Said metal electrode is arranged on the urceolus madial wall of all pressing shielding cylinder, is provided with insulating medium layer between metal electrode and the urceolus madial wall.

3. a kind of high-voltage strut formula suspension structure electronic current combination of voltages instrument transformer according to claim 1; It is characterized in that; Said metal electrode is arranged on the inner core lateral wall of all pressing shielding cylinder, is provided with insulating medium layer between metal electrode and the inner core lateral wall.

4. according to claim 2 or 3 described a kind of high-voltage strut formula suspension structure electronic current combination of voltages instrument transformers, it is characterized in that said metal electrode ground connection.

5. a kind of high-voltage strut formula suspension structure electronic current combination of voltages instrument transformer according to claim 4 is characterized in that, is parallel with the capacitance-resistance divider resistance between the input of said voltage signal acquisition unit.

6. a kind of high-voltage strut formula suspension structure electronic current combination of voltages instrument transformer according to claim 1 is characterized in that the coil of said electronic current mutual inductor is a Luo-coil.

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