CN102945739A - Power-frequency single-phase resonant transformer for calibration and boosting of voltage transformer - Google Patents

Abstract

The invention discloses a power frequency single-phase resonant transformer used for on-site verification and step-up of a voltage transformer. The transformer casing (4) is provided with a resonant transformer main body (2) and a compensation adjustable reactor (14). The resonant transformer The main body (2) is provided with a wire package (3), and the wire package (3) includes a low-voltage winding (10), a medium-voltage compensation winding (12) and a high-voltage winding (9), and the medium-voltage compensation winding (12) is provided with a medium-voltage tap , and connected with the compensation adjustable reactor (14) through the medium voltage tap. The power frequency single-phase resonant transformer provided by the present invention is connected to the compensation adjustable reactor through the medium voltage tap, and the inductive component is introduced to adjust the internal impedance of the resonant transformer and match the capacitance of the tested voltage transformer to form a The resonance test circuit can effectively reduce the input capacity of the low-voltage winding, and it is small in size and light in weight, which is convenient for on-vehicle verification of voltage transformers and has a good application prospect.

Description

Power frequency single-phase resonant transformer for voltage transformer calibration step-up

technical field

The invention relates to a power frequency single-phase resonant transformer used for on-site calibration and step-up of a 500 kV voltage transformer, belonging to the technical field of high-voltage power transmission and transformation.

Background technique

With the deepening of the reform of the power industry system, the accuracy of high-voltage metering devices such as power transformers is directly related to the fairness and rapid development of the power market. For testing, the 500kV voltage transformer is a fixed-installation high-voltage equipment and can only be tested on-site. When calibrating the 500kV voltage transformer, it is necessary to increase the power frequency of the tested voltage transformer to the rated voltage to simulate the tested voltage transformer. The actual operating status of the voltage transformer is compared with the standard voltage transformer to realize the value transfer work of the national standard. The voltage transformers with a voltage level of 500 kV are mostly capacitive voltage transformers, which are capacitive at electrical frequencies. Moreover, the voltage transformer under test cannot be disconnected during the field test, and the entire busbar or GIS pipeline needs to be boosted together, so that the input capacity of the low-voltage winding is added to the ground capacitance, and the additional ground capacitance is the same as the busbar or GIS. The length of the pipeline, the environment of the test site, the layout of overhead lines, etc. are related. It is an irregular and discrete value, which will affect the detection accuracy of the 500kV voltage transformer.

Contents of the invention

The purpose of the present invention is to overcome the problems in the prior art, and provide a power frequency single-phase resonant transformer for on-site verification and step-up of voltage transformers, which is equipped with a medium-voltage compensation winding to introduce inductive components, and can adjust the internal impedance of the resonant transformer , and matched with the capacitance of the tested voltage transformer to form a resonant test circuit, which effectively reduces the input capacity of the low-voltage winding, and is small in size and light in weight, which is convenient for vehicle-mounted voltage transformer on-site calibration and boosting. application prospects.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A power frequency single-phase resonant transformer used for on-site verification and step-up of voltage transformers, including a high-voltage bushing and a transformer casing, the high-voltage bushing is located above the transformer casing, and is characterized in that: the inside of the transformer casing is equipped with The main body of the resonant transformer and the compensation adjustable reactor. The main body of the resonant transformer is provided with a wire package. The wire package includes a low-voltage winding, a medium-voltage compensation winding and a high-voltage winding. The medium-voltage compensation winding is provided with a medium-voltage tap, and through The medium voltage tap is connected with the compensation adjustable reactor.

The aforementioned power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers is characterized in that: the wire wrap is connected to the fastener on one side of the main body of the resonant transformer through an insulating member.

The aforementioned power frequency single-phase resonant transformer used for on-site verification and step-up of voltage transformers is characterized in that: the wire package also includes iron core columns, and the low-voltage winding, medium-voltage compensation winding and high-voltage winding are connected from inside to outside Wrap around the iron core column in turn.

The aforementioned power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers is characterized in that: the wire wrap is fixed inside the transformer shell by a wire wrap fixing frame.

The beneficial effects of the present invention are: the power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers provided by the present invention is equipped with a medium voltage compensation winding, and is connected to the compensation adjustable reactor through a medium voltage tap , the introduction of inductive components can adjust the internal impedance of the resonant transformer, and form a resonant test circuit that matches the capacitance of the tested voltage transformer to effectively reduce the input capacity of the low-voltage winding, and is small in size and light in weight. Vibration measures are used to facilitate the vehicle-mounted on-site verification and boosting of 500 kV voltage transformers, which has a good application prospect.

Description of drawings

Fig. 1 is a schematic structural diagram of a power frequency single-phase resonant transformer used for on-site verification and step-up of voltage transformers according to the present invention.

Fig. 2 is a schematic structural view of the main body of the resonant transformer of the present invention.

Fig. 3 is a structural schematic diagram of the wire package of the present invention.

The meaning marks in the accompanying drawings are as follows:

1: High voltage bushing; 2: Main body of resonant transformer; 3: Wire package; 4: Transformer shell; 5: Fastener; 6: Insulator; 7: Iron core column; 8: Wire package fixing frame; 9: High voltage winding ; 10: low voltage winding; 11: compensation adjustable reactor; 12: medium voltage compensation winding.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, Figure 2 and Figure 3, the power frequency single-phase resonant transformer used for on-site verification and step-up of voltage transformers according to the present invention has a medium voltage compensation winding in the wire package, and the inductive component is introduced to adjust the resonant transformer internal impedance, thereby effectively reducing the input capacity, reducing the volume and weight of the test equipment and realizing vehicle-mounted. The specific structure includes a high-voltage bushing 1 and a transformer casing 4. The high-voltage bushing 1 is located above the transformer casing 4, and the transformer casing 4 Internally, there is a resonant transformer main body 2 and a compensation adjustable reactor 11. The main body of the resonant transformer 2 is provided with a wire package 3, and the wire package 3 includes a low-voltage winding 10, a medium-voltage compensation winding 12 and a high-voltage winding 9, and a medium-voltage compensation winding 12 A medium-voltage tap is provided and connected to the compensation adjustable reactor 11 through the medium-voltage tap. The compensation adjustable reactor 11 can adjust the inductance through the size of its air gap and change the internal impedance of the entire resonant transformer, so that The internal impedance of the resonant transformer is in an inductive state, and forms a resonant state with the tested 500 kV voltage transformer, which is capacitive in the supplementary test circuit. At this time, the input capacity of the low-voltage winding is 1/Q times the capacity of the high-voltage winding, and Q is the test circuit quality factor, effectively reducing the input capacity of the low-voltage winding, the wire pack 3 is connected to the fastener 5 on one side of the main body of the resonant transformer 2 through the insulator 6, and the wire pack 3 also includes an iron core column 7, a low-voltage winding 10, The medium-voltage compensation winding 12 and the high-voltage winding 9 are sequentially encircled on the iron core column 7 from the inside to the outside, and the wire package 3 is fixed inside the transformer shell 4 through the wire package fixing frame 8. The designed wire package 3 has a compact structure and a small volume , light weight, easy to realize the vehicle-mounted voltage transformer on-site calibration step-up, here the line package fixing frame 8, transformer shell 4 and high-voltage bushing 1 are equipped with anti-vibration measures, and SF6 gas insulation is used to meet the vehicle-mounted It meets the needs of design and has a good application prospect.

The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. What are described in the above-mentioned embodiments and the description only illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have Variations and improvements are possible, which fall within the scope of the claimed invention. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (4)

1. A power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers, including a high-voltage bushing (1) and a transformer casing (4), and the high-voltage bushing (1) is located above the transformer casing (4) , characterized in that: the transformer shell (4) is provided with a resonant transformer main body (2) and a compensation adjustable reactor (14), and the resonant transformer main body (2) is provided with a wire package (3), and the wire The package (3) includes a low-voltage winding (10), a medium-voltage compensation winding (12) and a high-voltage winding (9). The medium-voltage compensation winding (12) is provided with a medium-voltage tap, and the compensation can The reactor (11) is connected with each other. 2. The power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers according to claim 1, characterized in that: the wire package (3) is connected to the main body of the resonant transformer (2) through an insulating member (6) ) to the fastener (5) on one side. 3. The power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers according to claim 1, characterized in that: the wire package (3) also includes an iron core column (7), and the low voltage The winding (10), the medium voltage compensation winding (12) and the high voltage winding (9) are wound around the iron core column (7) in turn from inside to outside. 4. The power frequency single-phase resonant transformer used for on-site verification and boosting of voltage transformers according to claim 1, characterized in that: the wire package (3) is fixed on the transformer shell by the wire package fixing bracket (8) (4) INTERNAL.

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