How to classify the different characteristics of voltage transformers?

According to the purpose, it is divided into measuring voltage transformers and protection voltage transformers

I.The measuring voltage transformers or the measuring winding of the voltage transformer: in the normal voltage range, to provide the grid voltage information to the measuring and measuring device;

II.The protection voltage transformers or the protection winding of voltage transformer: in the state of power grid fault, to relay protection devices to provide power grid fault voltage information.

According to the insulating medium, it can be divided into dry type, inflatable type, pouring type and oil immersion type.

I .The dry type voltage transformer has a simple structure and is not likely to explode at all. However, its insulation strength is relatively low, so it is only suitable for indoor devices under 6kV.

II.The castable insulated voltage transformer has a compact design and construction, and is cast by epoxy resin or other resin mixed materials. It is especially easy to maintain and maintain in the later stage, and is more suitable for the indoor installation of 3kV to 35kV.

III.The insulation performance of oil-immersed voltage transformer is taken as insulation by insulating paper and insulation oil, which is the most common structure type in China.

IV.Inflatable insulated voltage transformer, with gas as the main insulation, is usually used in higher voltage levels, so it is suitable for use in electrical appliances with strong sealing property. It is more suitable for use in SF6 fully enclosed electrical appliances.

According to the phase number, the voltage transformer can be divided into two modes, one is monomial, the other is three-phase type.

It should be noted that the voltage transformer over 35kV cannot be made into three-phase type. Most of the products are single-phase, because the capacity of the voltage transformer is small, the volume of the device is not large, and the internal and external insulation requirements between the three-phase high-voltage bushings are difficult to meet, so only 3-15KV products sometimes adopt three-phase structure.

According to the principle of voltage transformation, it is divided into electromagnetic voltage transformer and capacitive voltage transformer and photoelectric voltage transformer

I.Electromagnetic voltage transformer: according to the principle of electromagnetic induction, the whole voltage can be transformed in different ways

In terms of basic structure and principle, the actual transformer is basically consistent with that in China, which is more common in the following use.

II.Capacitive voltage transformers: the main components can be divided into intermediate transformers, capacitive voltage dividers, dampers, Compensatory reactor and carrier device, more often used in neutral point ground system, it is actually just a single capacitor voltage tube, is a number of identical capacitor series combination, device on the ground and high voltage phase line

In the middle, mainly used as power measurement, carrier communication, voltage measurement and relay protection.

III.Photoelectric voltage transformers: basically, the principle of photoelectric transformation is used to realize voltage transformation. So this transformer is still under development.

According to the conditions of use, it is divided into indoor voltage transformers and outdoor voltage transformers.

I.Indoor voltage transformer: installed in indoor power distribution device, generally used in 35kV and below voltage level;

II.Outdoor voltage transformers: installed in outdoor power distribution devices, usually in the voltage level of 35kv and above.

If according to the number of windings to differentiate into three winding voltage transformer and double winding voltage transformer.

According to the operation state of the primary winding to earth, it is divided into the voltage transformer with the primary winding grounded and the voltage transformer with the primary winding ungrounded.

I.Voltage transformer with primary winding grounded: the terminal of the primary winding of single-phase voltage transformer or the neutral point of the primary winding of three-phase voltage transformer is directly grounded;

II.Voltage transformer with ungrounded primary winding: Both terminals of primary winding of single-phase voltage transformer are insulated to ground; All parts of the primary winding of the three-phase voltage transformer, including the wiring terminals, are insulated from the ground, and the insulation level is consistent with the rated insulation level.

According to the structure of magnetic circuit, it is divided into single stage voltage transformer, series voltage transformer and combined type voltage transformer.

I. Single-stage voltage transformer: the primary and secondary windings can be set into multiple secondary windings according to different requirements, and wound on the same iron core at the same time, but the iron core must be based on ground. In China, the single-stage voltage transformer is basically used for this and the following voltage levels.

II. Cascade type voltage transformer: On a winding can be divided into several different number of turns, the number of turns of the same unit directly concatenated in phase and ground, between each different unit must have own core, so core on quantity is more, and iron core with high voltage, the secondary winding can according to need, set up a number of different secondary winding, And the connection between it and the ground, the domestic voltage level is more commonly used in this type of structure.

III. Combined type transformer: It is mainly made of current transformer. And the voltage transformer is combined to form an integrated transformer, which can be referred to as the combined type transformer for short. However, the combined electrical matching transformer is also referred to as the combined type transformer.

We manufacture various precision current transformers and voltage transformers, which are widely used in electric power, energy, telecommunication, railway, industrial control and other fields.

If you have any needs, pls be free to contact us, we welcome customers to customize.

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