CN201251622Y - Heavy current up-flow aggregate unit for field test of 750v current transformator - Google Patents

Abstract

The utility model relates to a large current booster combination device for field test of 750kV current transformer, which is composed of a plurality of independent current booster units adopting annular iron core and wire transposition winding output winding, and the input of each current booster unit The winding ends are connected in parallel with each other, and the output winding ends are connected in series, parallel or series-parallel hybrid; each upcycler unit is made of anti-rust aluminum plate as the box body, and stainless steel plate as the panel. The utility model is characterized by high output voltage under the condition of large current, which solves the problem of current source for large load and high current test and the problem of large current rise for field test of 750kV GIS, HGIS and tank type switch current transformer, and has a structure Simple and reasonable, convenient for transportation and on-site installation and use, and good on-site test and detection effect.

Description

750kV current transformer field test with large current boosting combined device

technical field

The utility model belongs to the technical field of general equipment for power frequency ultra-high voltage and large current testing, and relates to a combined test device for on-site high-current up-current, in particular to a 750kV GIS, HGIS and tank-type switch current transformer on-site The design concept of the large current boosting combination device used in the test can also be applied to the temperature rise of high current equipment or the current source for other tests.

Background technique

With the establishment of 750kV power grids in Northwest China, the power exchange settlement and power grid loss assessment of AC UHV power grids rely on the on-site detection of the error characteristics of voltage transformers and current transformers in many aspects.

At present, my country's 750kV substations include two types: open substations and GIS gas-insulated combined substations. In the past, independent current transformers were used in 500kV substations. On-site testing was relatively easy, and the work was carried out relatively smoothly. However, tank circuit breakers with current transformers at voltage levels of 750kV and above and GIS stations have large test circuit impedance, so the test current To reach more than 4kA, the test is very difficult, that is to say, the current value applied in the field test of the current transformer is difficult to reach the rated value. In recent years, State Grid Wuhan High Voltage Research Institute, Shandong Electric Power Test Research Institute, Sichuan Electric Power Test Research Institute and other units have done a lot of work in theory and engineering implementation, but the field test only increased the test circuit current of the 500kVGIS station. To 3kA, the test current can not reach the rated value will directly affect the accuracy and reliability of grid electric energy measurement. A 500kV GIS station in Sichuan area once tested the error test of a current transformer with a rated current of 4kA at a tap of 2kA and found that the basic error has exceeded the tolerance. At 3kA, the basic error curve has shifted, and the higher The test current cannot be carried out at all due to equipment reasons, and it can only be calculated theoretically that the transformer may be seriously out of tolerance under an enlarged current (4.8kA).

On the other hand, the existing high-current boosting equipment is all configured in a dedicated laboratory. Due to the requirement of sufficient capacity, it must be powered by a dedicated line power supply and used for fixed use. If it is directly used for large-load and high-current field test detection, there There are many problems such as bulky and unable to be transported, poor resistance to external impact of equipment, poor heat dissipation performance, limited installation and placement space, difficulty in solving on-site safe wiring (ground) and power capacity configuration, and serious eddy current loss and temperature rise of equipment.

Utility model content

The purpose of the utility model is to solve the problems existing in the prior art, and further provide a large current boosting combined device for field testing of 750kV current transformers with simple and reasonable structure, convenient transportation and on-site installation and use, and good test and detection effect.

The technical solution adopted in order to realize the purpose of the above invention is as follows: the provided 750kV current transformer field test high-current boosting combination device consists of multiple independent boosting devices that use annular cores and wire transposition winding output windings. The input winding ends of each uplifter unit are connected in parallel, and the output winding ends are connected in series, parallel or a combination of series and parallel; each uplifter unit is made of anti-rust aluminum plate and stainless steel plate Make panels. In practical applications, a large current boosting combination device is formed by connecting multiple current booster units in series, parallel or series-parallel, so that the equipment can obtain the required output current and output voltage while simplifying the equipment structure. Thus, the problems of transportation of high-current equipment, resistance to external impact, heat dissipation, safety grounding, eddy current loss and temperature rise are completely solved.

The utility model is characterized by high output voltage under the condition of large current, and then solves the current source problem of large load and high current test. For the problem of rising current, the implementation and application of this device has changed the current situation that the current transformers above 4kA in 750kV substations in my country cannot be detected by direct methods, and has made contributions to the accuracy and reliability of national energy measurement.

Description of drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present utility model - a full-series upflow combination device.

Fig. 2 is another embodiment of the utility model - a schematic structural view of a full-parallel upflow combination device.

Fig. 32 is a schematic structural view of the third embodiment of the present invention - a series-parallel hybrid upflow combination device.

Detailed ways

The utility model will be further described below in conjunction with the accompanying drawings and embodiments, but the actual production structure of the utility model is not limited to the illustrated embodiments.

Referring to the accompanying drawings, the 750kV current transformer field test of the utility model is composed of 2 to 10 independent current booster units with the same model and structure (considering the internal resistance matching of the current booster) and output efficiency, it is recommended that the number of booster units is less than or equal to 10), each unit is made of anti-rust aluminum plate as the box body, and stainless steel plate as the panel, thus solving the transportation of high-current equipment, resistance to external shocks, heat dissipation, and safe grounding , Eddy current loss and temperature rise. In terms of design structure, each booster unit adopts a ring-shaped core, and the output winding adopts the technology of transposing multiple wires on the ring-shaped core evenly, and each wire is specially insulated. Then use the aluminum row to lead out. This structure can reduce the leakage reactance of the current booster unit, reduce the internal loss, and reduce the contact resistance of the external primary circuit wiring, thereby realizing the effective transfer of energy, and at the same time solving the skin effect and effective The local saturation phenomenon of the iron core caused by the uneven excitation is avoided. In terms of device connection, each booster unit is provided with two sets of independent output windings, and the ends of the same output windings of each booster unit are connected in series, parallel or a combination of series and parallel, so that the output can be more combination type. In addition, a compensation winding tap is added to the input winding of each booster unit to change the winding voltage to adjust the output voltage. This can ensure the maximum output current at a certain capacity without changing the boost. The wiring method of the converter group.

The accompanying drawings describe typical applications of the device described in the present invention by taking different combinations of four uplift units as examples.

Typical application 1: As shown in Figure 1, the output winding terminals L ₁ and L ₂ of each up-converter unit T ₁ , T ₂ , T ₃ , and T ₄ are all connected in series, and the input winding terminals S—S ₃ are connected in parallel. According to this principle Wiring can form a current booster with a maximum output voltage of 240V and a minimum output current of 2.5kA.

Typical application two: As shown in Figure 2, the output winding terminals L ₁ and L ₂ of each up-converter unit T ₁ , T ₂ , T ₃ , and T ₄ are all connected in parallel, and the input winding terminals S—S ₃ are connected in parallel. According to this principle Wiring can form a current booster with a minimum output voltage of 30V and a maximum output current of 10kA.

Typical application 3: The output winding terminals L ₁ and L ₂ of each current booster unit T ₁ , T ₂ , T ₃ , and T ₄ are connected in a series-parallel hybrid manner as shown in Figure 3, and the output voltage can be formed by wiring according to this schematic diagram 120V, a current booster with an output current of 5kA.

Claims (3)

1, a kind of 750kV current mutual inductor on site is tested with big electric current up-flow composite set, it is characterized in that it is made up of the independently current lifting device unit of a plurality of employing ring-shaped cores and wire transposition coiling output winding, the input winding terminal of each current lifting device unit is parallel with one another, and the output winding terminal links by series, parallel or connection in series-parallel hybrid mode; Each current lifting device unit all adopts rustproof aluminium sheet to make casing, and adopts corrosion resistant plate to make panel.

2,750kV current mutual inductor on site according to claim 1 is tested with big electric current up-flow composite set, it is characterized in that each current lifting device unit is provided with two groups and independently exports winding, link by series, parallel or connection in series-parallel hybrid mode between the identical output winding in each current lifting device unit end of the same name.

3,750kV current mutual inductor on site test according to claim 1 is characterized in that all having additional the compensation tapping on the input winding of each current lifting device unit with big electric current up-flow composite set.

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