CN114334405A - Generator transformer - Google Patents

Abstract

The invention relates to a generator transformer, especially provides a generator transformer with voltage regulating function at high voltage side and low voltage side, comprising: a transformer core; the low-voltage winding, the high-voltage winding and the high-voltage regulating winding are wound on the transformer iron core; a high voltage regulating switch module connecting the high voltage regulating winding and the high voltage winding in series; and a low-voltage regulating winding, a low-voltage regulating switch module, a low-voltage excitation winding, a low-voltage series winding and a regulating transformer which are required for realizing the purpose of low-voltage regulation. The voltage regulating transformer is additionally arranged on the basis of the existing generator transformer to provide the required variable magnetic flux function, and the low-voltage regulating winding, the low-voltage regulating switch module, the low-voltage excitation winding and the low-voltage series winding which are related to the voltage regulating transformer are correspondingly introduced, so that the low-voltage regulating function can be smoothly realized in a variable magnetic flux mode under the control of the corresponding switch module, and the performances of the power quality stability and the like of a power system are obviously improved.

Description

Generator transformer

Technical Field

The application relates to the field of transformers, and particularly provides a generator transformer with voltage regulating functions on a high-voltage side and a low-voltage side.

Background

Generator transformers are known in the art, wherein in the usual case on one side (low voltage side or input side) of the generator transformer at least one generator is connected as a power input with the low voltage winding of the generator transformer (which belongs to the low voltage system); on the other side (high-voltage side or output side) of the generator transformer, the voltage boosted by the electromagnetic induction principle is output from the high-voltage winding of the generator transformer (which belongs to the high-voltage system), for example, to be connected to the grid.

As a representative of the above generator transformers, three-system generator transformers including two low-voltage systems and one high-voltage system are gradually gaining wider use in the art. For the three-system generator transformer, under normal working conditions, the low-voltage side of the transformer is connected with two power supply sources (namely a first generator and a second generator), and correspondingly, two low-voltage systems exist, wherein the first generator is connected with the first low-voltage system as a first power input, and the second generator is connected with the second low-voltage system as a second power input.

Aiming at the traditional three-system generator transformer, only the high-voltage side (or the high-voltage system) has a voltage regulating function, and the low-voltage side (two low-voltage systems) has constant voltage, so that the working condition or occasion that the low-voltage system also has a voltage regulating requirement can not be met obviously. In addition, for example, when a wind turbine generator operating in a wind power generation mode is used as a power supply source of the three-system generator transformer, the stability of the power on the power supply side is generally poor, that is, the voltage fluctuation on the generator side is large, which has an adverse effect on ensuring the continuity of power supply and the quality of power supply.

On the basis of the above background, there is a higher or new need for a generator transformer having a voltage regulation function on both the high-voltage side and the low-voltage side, so as to be able to overcome or eliminate at least partially the above-mentioned deficiencies or drawbacks of the prior art and further improve the performance of the power system, such as the stability of the quality of the electrical energy.

Disclosure of Invention

In view of this, the present application proposes a generator transformer, comprising:

a transformer core;

the low-voltage winding is wound on the transformer iron core and is connected with an external generator so as to receive power input from the external generator;

a high-voltage winding wound around the transformer core, wherein the voltage raised by the electromagnetic induction principle is output from the high-voltage winding;

the high-voltage regulating winding is wound on the transformer iron core; and

a high voltage regulating switch module connecting the high voltage regulating winding and the high voltage winding in series,

wherein, generator transformer still includes low pressure regulating winding, low pressure regulating switch module, low pressure excitation winding, low pressure series winding and regulating transformer, regulating transformer includes regulating transformer core, low pressure regulating winding twine in on the transformer core, low pressure excitation winding twine in on the regulating transformer core and regard as regulating transformer's input winding, low pressure series winding twine in on the regulating transformer core and regard as regulating transformer's output winding, the first end of low pressure regulating winding with the first end of low pressure excitation winding links to each other, the second end of low pressure regulating winding via the low pressure regulating switch module with the second end of low pressure excitation winding links to each other, the number of turns of low pressure excitation winding is greater than the number of turns of low pressure series winding, the first end of low pressure winding with a wiring end of outside generator links to each other, the second end of the low-voltage winding is connected with the first end of the low-voltage series winding, and the second end of the low-voltage series winding is connected with the other terminal of the external generator, so that a current flowing path flowing into the low-voltage winding from the first end of the low-voltage winding and flowing through the low-voltage winding and the low-voltage series winding and then flowing out of the second end of the low-voltage series winding is provided.

According to a feasible implementation mode, the low voltage tap changer module is a mechanical on-load tap changer, the low voltage regulating winding is provided with a plurality of taps, a tap selector is arranged in the mechanical on-load tap changer, in the working process of the generator transformer, based on the switching of the tap selector between different connection positions, the tap selector is connected with one of the taps, and therefore the effective number of turns of the low voltage regulating winding is changed.

According to a feasible implementation mode, the transformer core adopts a shell type structure comprising a central core column and two side yokes, and the low-voltage winding, the high-voltage regulating winding and the low-voltage regulating winding are wound on the central core column of the transformer core.

According to a feasible implementation manner, the high-voltage regulating winding and the low-voltage regulating winding are wound on the central core column of the transformer core in a cylinder shape, and the high-voltage regulating winding and the low-voltage regulating winding have the same cylinder radius relative to the central axis of the central core column.

According to a feasible embodiment, the low voltage winding comprises a first low voltage winding and a second low voltage winding, the generator transformer comprises a first low voltage regulating winding, a first low voltage regulating switch module, a first low voltage exciting winding, a first low voltage series winding and a second low voltage regulating winding, a second low voltage regulating switch module, a second low voltage exciting winding, a second low voltage series winding, wherein a first end of the first low voltage regulating winding is connected with a first end of the first low voltage exciting winding, a second end of the first low voltage regulating winding is connected with a second end of the first low voltage exciting winding via the first low voltage regulating switch module, the number of turns of the first low voltage exciting winding is greater than that of the first low voltage series winding, the first end of the first low voltage winding is connected with a terminal of the external generator, the second end of the first low-voltage winding is connected with the first end of the first low-voltage series winding, and the second end of the first low-voltage series winding is connected with the other terminal of the external generator, so that a current flowing path flowing into the first end of the first low-voltage winding and flowing through the first low-voltage winding and the first low-voltage series winding and then flowing out of the second end of the first low-voltage series winding is provided; the first end of the second low-voltage regulating winding is connected with the first end of the second low-voltage excitation winding, the second end of the second low-voltage regulating winding is connected with the second end of the second low-voltage excitation winding through the second low-voltage regulating switch module, the number of turns of the second low-voltage excitation winding is greater than that of the second low-voltage series winding, a first end of the second low-voltage winding is connected with one terminal of another external generator, a second end of the second low-voltage winding is connected with a first end of the second low-voltage series winding, a second end of the second low-voltage series winding is connected with the other terminal of the other external generator, thereby providing a current flow path from a first end of the second low voltage winding into and through the second low voltage winding, the second low voltage series winding, and then out a second end of the second low voltage series winding.

According to a feasible implementation mode, the regulating transformer iron core adopts a core type structure comprising two core columns, the first low-voltage excitation winding and the first low-voltage series winding are wound on one core column of the regulating transformer iron core, and the second low-voltage excitation winding and the second low-voltage series winding are wound on the other core column of the regulating transformer iron core.

According to a feasibility implementation mode, the regulating transformer iron core includes first iron core and second iron core, first iron core with the second iron core is independent each other, first iron core adopts the shell type structure including a central stem and two other yokes, first low pressure encourage winding with first low pressure series winding all twine in on the central stem of first iron core, the second iron core adopts the shell type structure including a central stem and two other yokes, second low pressure encourage winding with second low pressure series winding all twine in on the central stem of second iron core.

According to a possible embodiment, assuming that the number of turns of the low voltage excitation winding is T1 and the number of turns of the low voltage series winding corresponding thereto is T2, the following relation is satisfied between the number of turns of the low voltage excitation winding and the number of turns of the low voltage series winding: T1/T2 ═ N, where N is an integer greater than 1.

According to a possible embodiment, N is equal to 6.

According to a possible embodiment, the generator transformer is a single-phase generator transformer or a three-phase generator transformer.

According to the scheme, the voltage regulating transformer is additionally arranged on the basis of the existing generator transformer to provide the required variable magnetic flux function, and the low-voltage regulating winding, the low-voltage regulating switch module, the low-voltage excitation winding and the low-voltage series winding which are related to the voltage regulating transformer are correspondingly introduced, so that the preset low-voltage regulating function can be smoothly realized in a variable magnetic flux mode under the control of the corresponding switch module, the generator transformer with the voltage regulating function on the high-voltage side and the low-voltage side can be provided in a simple and reliable mode, the defects or shortcomings in the prior art are overcome, and the performances such as the power quality stability and the like of a power system are obviously improved.

Drawings

The foregoing and other features and advantages of the present application will become more apparent to those of ordinary skill in the art to which the present application pertains by describing in detail preferred embodiments thereof with reference to the accompanying drawings, wherein:

fig. 1 is a typical schematic wiring diagram of a conventional three-system generator transformer having a voltage regulating function on the high-voltage side.

Fig. 2 is a schematic electrical schematic diagram of a switch module that may be used in the high voltage regulation system of the three-system generator transformer shown in fig. 1.

Fig. 3 is a schematic diagram of a typical core structure and its associated winding configuration of the three-system generator transformer shown in fig. 1.

Fig. 4 is a schematic wiring diagram of a generator transformer according to an exemplary embodiment of the present application.

Fig. 5 is an electrical schematic diagram of a switch module that may be used in the low voltage regulation system of the generator transformer shown in fig. 4.

Fig. 6A-6C are schematic diagrams of the core structure and its associated winding configuration of the generator transformer shown in fig. 4.

Fig. 7 is a schematic diagram of a typical core structure of a regulating transformer and its associated winding configuration that may be used in the low voltage regulating system of the generator transformer shown in fig. 4.

Wherein the reference numbers are as follows:

1 a: a first low voltage winding inner layer; 1 b: a first low voltage winding outer layer; 2 a: a second low voltage winding inner layer; 2 b: a second low voltage winding outer layer; 3 a: a first high voltage winding; 3 b: a second high voltage winding; 4 a: a first high voltage regulating winding; 4 b: a second high voltage regulating winding; 5 a: a first low voltage regulating winding; 5 b: a second low voltage regulating winding; 6 a: a first low voltage regulation switch module; 6 b: a second low voltage regulating switch module; 7 a: a first low voltage excitation winding; 7 b: a second low voltage excitation winding; 8 a: a first low voltage series winding; 8 b: a second low voltage series winding; 9: a high voltage regulating switch module; w1, transformer main winding; w2, a first winding of a voltage regulating transformer; w3, a second winding of the voltage regulating transformer; 11, a transformer iron core; 12, regulating transformer iron core; LH1 head end of the first low voltage winding; LE1 tail end of first low voltage winding; LH2, head end of the second low voltage winding; LE2, tail end of second low voltage winding; HH: a head end of the high voltage winding; HE: the tail end connector of the high-voltage regulating switch module; AE1, tail end of the first low-voltage series winding; AE2 is the tail end of the second low-voltage series winding; k1, a first switch joint; k2 second switch connector.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clear, the present application is further described in detail below by way of examples with the aid of the embodiments and with reference to the accompanying drawings.

It should be understood that the embodiments and their associated descriptions presented below are to be considered exemplary and not limiting of the present application. Further, it is to be noted that the same reference numerals are used for substantially the same or similar parts in different drawings to avoid repetitive description as much as possible. In addition, the sizes, positions, and the like of the respective portions in the drawings are not drawn strictly to scale, and the sizes, the proportional relationships, and the like of the respective portions should not be construed as limiting the present application.

Before describing the technical solution of the present application in detail, first, an electrical connection manner of a conventional three-system generator, which is a typical representative of a generator transformer, and a voltage regulation principle thereof will be briefly described.

Fig. 1 is a typical schematic wiring diagram of a conventional three-system generator transformer with voltage regulation function on the high-voltage side, wherein it should be noted that, for simplicity, the wiring manner of the three-system generator transformer in a single phase is illustrated in fig. 1. For a three-phase three-system generator transformer, the connection mode is basically similar, but the number of phases is changed from single phase to three phase.

As shown in fig. 1, the three-system generator transformer generally includes two low-voltage windings, i.e., a first low-voltage winding and a second low-voltage winding, on the low-voltage side, which are respectively main components of two low-voltage systems (i.e., a first low-voltage system and a second low-voltage system). The first low voltage winding may for example take the form of a double-layer structure comprising a first low voltage winding inner layer 1a and a first low voltage winding outer layer 1b, the first low voltage winding inner layer 1a and the first low voltage winding outer layer 1b being connected to each other in series and connected to an external generator at the upper part as shown in fig. 1 by a head end LH1 and a tail end LE1 of the first low voltage winding. The second low voltage winding may also take the form of a double-layer structure, for example, comprising a second low voltage winding inner layer 2a and a second low voltage winding outer layer 2b, the second low voltage winding inner layer 2a and the second low voltage winding outer layer 2b being connected in series with each other and connected to another external generator at the lower part as shown in fig. 1 by a head end LH2 and a tail end LE2 of the second low voltage winding.

In addition, as shown in fig. 1, the three-system generator transformer is provided with a high-voltage winding on the high-voltage side as an important component of the high-voltage system, and in order to meet the use requirement of the voltage regulation function on the high-voltage side, the three-system generator transformer is also provided with a high-voltage regulation winding which is a part of the high-voltage regulation system.

More specifically, as shown in fig. 1, in order to reduce the circulating current in the high-voltage system under the asymmetric magnetic field operation condition due to the presence of a half-cross operation condition of the low-voltage system and the whole high-voltage system in such a three-system generator transformer, the three-system generator transformer usually comprises two high-voltage windings, i.e. a first high-voltage winding 3a and a second high-voltage winding 3b, on the high-voltage side, and accordingly comprises two high-voltage regulating windings, i.e. a first high-voltage regulating winding 4a and a second high-voltage regulating winding 4b, the first high-voltage winding 3a and the second high-voltage winding 3b are usually designed in an upper-lower two-part (two-half) structure, the upper-lower two-part (i.e. the first high-voltage winding 3a and the second high-voltage winding 3b) are connected in parallel, and the first high-voltage regulating winding 4a and the second high-voltage regulating winding 4b are usually also designed in an upper-lower-part, The lower two-part (two-half) structural design, the upper and lower two parts (i.e., the first high-voltage regulating winding 4a and the second high-voltage regulating winding 4b) are connected in parallel. The middle tap between the first high-voltage winding 3a and the second high-voltage winding 3b is led out through the head end HH of the high-voltage winding, the tail ends of the first high-voltage winding 3a and the second high-voltage winding 3b are connected with the head end (first end) of the high-voltage regulating switch module 9 together, and the tail end (second end) of the high-voltage regulating switch module 9 can be led out through the tail end connector HE. The required high voltage regulation function can be realized by the electrical connection with different voltage regulation taps (taps) of the first high voltage regulation winding 4a or the second high voltage regulation winding 4b through the selection or switching of different connection positions by the high voltage regulation switch module 9 (in particular, based on a tap selector provided in the high voltage regulation switch module 9). The high voltage regulator system of fig. 1 is shown, by way of example, as having 4 regulator stages, provided with 5 (i.e. 4+1) regulator taps, but in practice the number of regulator stages may be designed to be any integer greater than 1, depending on the particular requirements.

Fig. 2 shows a schematic electrical schematic of a high voltage regulating switch module that may be used in the high voltage regulating system of the three system generator transformer shown in fig. 1. As shown in fig. 2, the high voltage tap changer module 9 may adopt a conventional mechanical on-load tap changer known in the art, which has the advantages of simple structure, low cost, etc. The specific structure, circuit composition and operation principle of the mechanical on-load tap-changer are known in the art and only need to be selectively applied, so that the detailed description thereof is omitted herein.

As can be seen in connection with fig. 2, taking one of the high voltage windings, i.e. the first high voltage winding 3a as an example, in operation of the high voltage regulation system in the three-system generator transformer, the tail end of the first high voltage winding 3a may be connected to the first switch connector K1 in fig. 2, by electrically connecting the high-voltage regulator switch module 9 (in particular, with different taps (voltage-regulating taps) of the first high-voltage regulator winding 4a by selecting or switching different connection positions based on a tap selector provided therein), it is possible to string different numbers of turns of the first high-voltage regulator winding 4a into the first high-voltage winding 3a, that is, the high-voltage regulating winding with different turns is connected in series, and then the high-voltage regulating winding is led out through a relevant connector or terminal (such as a lead-out connector shown at the upper right part in fig. 2) of the high-voltage regulating switch module 9, so that the required high-voltage regulating function can be smoothly realized.

It should be noted that the electrical schematic shown in fig. 2 is merely schematic for simplicity, wherein the number of voltage regulator taps (taps) of the high voltage regulator winding (and corresponding tap selectors) shown does not correspond exactly to the number of voltage regulator taps in the high voltage regulator system shown in fig. 1. In fact, as mentioned above, the number of voltage regulation taps and the corresponding voltage regulation stages can be freely chosen according to the actual situation.

Fig. 3 schematically illustrates a typical core structure and its associated winding configuration of the three-system generator transformer shown in fig. 1. As shown in fig. 3, the transformer core 11 has a shell structure including a central core column and two side yokes, wherein the two low-voltage windings, the two high-voltage windings and the two high-voltage regulating windings (collectively referred to as transformer main winding W1) are all wound (or sleeved) on the central core column of the transformer core 11, and no winding is wound on the two side yokes of the transformer core 11, which is only used for forming a magnetic circuit of the transformer core 11, and such a core is also referred to as 1/2 type core in the art.

As mentioned before, with the above-mentioned conventional three-system generator transformer, which has a voltage regulating function only on the high-voltage side (i.e. it is provided with a high-voltage regulating winding and is part of a high-voltage regulating system), it is obviously not possible to adapt to situations or conditions where there is a voltage regulating requirement on both the high-voltage side and the low-voltage side.

It is after the recognition of the above drawbacks or deficiencies of the prior art that the inventors of the present application propose a completely new solution that enables to provide a generator transformer with voltage regulation functionality on both the high voltage side and the low voltage side, i.e. both the high voltage system and the low voltage system.

In particular, according to an exemplary embodiment of the present application, a generator transformer having a voltage regulation function on both high and low voltage sides (i.e., a high voltage system and a low voltage system) is provided, which may be improved on the basis of the conventional three-system generator transformer shown in fig. 1.

The generator transformer according to the exemplary embodiment of the present application is described in detail below with reference to fig. 4 to 7 so that the basic principles and structural design aspects of the present application can be clearly understood. It is noted that for the sake of convenience of description, the exemplary embodiments of fig. 4-7 are described by way of example with a three-system generator transformer having two low-voltage systems and one high-voltage system, but the application is obviously not limited thereto.

First, fig. 4 shows a schematic wiring diagram of a generator transformer according to this exemplary embodiment of the present application.

As shown in fig. 4, the generator transformer comprises two low voltage windings on the low voltage side, i.e. a first low voltage winding and a second low voltage winding, as in fig. 1, wherein the first low voltage winding comprises a first low voltage winding inner layer 1a and a first low voltage winding outer layer 1b, which may for example take the form of a double layer structure. The second low voltage winding comprises a second low voltage winding inner layer 2a and a second low voltage winding outer layer 2b, which may for example take the form of a double layer structure. Furthermore, as in fig. 1, the generator transformer comprises two high-voltage windings, a first high-voltage winding 3a and a second high-voltage winding 3b, on the high-voltage side, and correspondingly two high-voltage regulating windings, a first high-voltage regulating winding 4a and a second high-voltage regulating winding 4 b. The first high-voltage winding 3a, the second high-voltage winding 3b, the first high-voltage regulating winding 4a and the second high-voltage regulating winding 4b can adopt the same wiring mode as that in fig. 1, so the wiring mode is omitted in fig. 4 and is not repeated.

In a conventional generator transformer, because the current of a low-voltage system is generally large, a proper switch cannot be selected to realize a voltage regulating function on a low-voltage side in a conventional design. In order to solve the problem, according to an exemplary technical scheme of the application, a low-voltage regulating system is additionally arranged in the three-system generator transformer, and a required low-voltage regulating function is realized in a flux-changing mode by means of the additionally arranged regulating transformer.

More specifically, as shown in fig. 4, the generator transformer in fig. 4 further includes two low voltage regulation systems, i.e., a first low voltage regulation system and a second low voltage regulation system, corresponding to the two low voltage windings, i.e., a first low voltage winding including a first low voltage winding inner layer 1a and a first low voltage winding outer layer 1b, and a second low voltage winding including a second low voltage winding inner layer 2a and a second low voltage winding outer layer 2 b. The first low-voltage regulating system comprises a first low-voltage regulating winding 5a, a first low-voltage regulating switch module 6a, a first low-voltage excitation winding 7a and a first low-voltage series winding 8 a. The second low-voltage regulating system comprises a second low-voltage regulating winding 5b, a second low-voltage regulating switch module 6b, a second low-voltage excitation winding 7b and a second low-voltage series winding 8 b. The first low voltage regulating winding 5a and the second low voltage regulating winding 5b may be respectively wound on a central core column of the transformer core 11 as a part of a transformer main body winding W1 shown in fig. 3, and are respectively connected with the first low voltage excitation winding 7a and the second low voltage excitation winding 7b via the first low voltage regulating switch module 6a and the second low voltage regulating switch module 6 b. The first low-voltage excitation winding 7a and the second low-voltage excitation winding 7b can be respectively wound on the additionally arranged regulating transformer iron core and are respectively and respectively electromagnetically coupled with the first low-voltage series winding 8a and the second low-voltage series winding 8b which are also respectively wound on the additionally arranged regulating transformer iron core. A first low voltage series winding 8a and a second low voltage series winding 8b may be connected in series with the first low voltage winding and the second low voltage winding, respectively.

More specifically, for example, a first end of the first low voltage regulating winding 5a is connected to a first end of the first low voltage excitation winding, a second end of the first low voltage regulating winding 5a is connected to a second end of the first low voltage excitation winding 7a via the first low voltage regulating switch module 6a, the number of turns of the first low voltage excitation winding 7a is designed to be larger than that of the first low voltage series winding 8a, the first end of the first low voltage winding is connected to one terminal of an external generator, the second end of the first low voltage winding is connected to the first end of the first low voltage series winding 8a, and the second end of the first low voltage series winding 8a, namely, a tail end AE1 (which may be a tail end of the first low voltage regulating system) is connected to the other terminal of the external generator, thereby providing a current flowing from the first end of the first low voltage winding into and through the first low voltage winding, A current flow path flowing from the second end of the first low voltage series winding 8a after the first low voltage series winding 8 a.

Similarly, for example, a first end of the second low voltage regulating winding 5b is connected to a first end of the second low voltage excitation winding 7b, a second end of the second low voltage regulating winding 5b is connected to a second end of the second low voltage excitation winding 7b via the second low voltage regulating switch module 6b, the number of turns of the second low voltage excitation winding 7b is designed to be larger than that of the second low voltage series winding 8b, the first end of the second low voltage winding is connected to one terminal of another external generator, the second end of the second low voltage winding is connected to the first end of the second low voltage series winding 8b, and the second end of the second low voltage series winding 8b, namely, the tail end AE2 (which may be the tail end of the second low voltage regulating system) is connected to the other terminal of the another external generator, so that the current flowing from the first end of the second low voltage winding to the second low voltage excitation winding can be provided, A current flow path from a second end of the second low voltage series winding 8b after the second low voltage series winding 8 b.

Fig. 6A-6C schematically show the core structure of the generator transformer shown in fig. 4 and its associated winding arrangement, respectively, from which the structural design of the generator transformer can be more intuitively understood.

As can be seen from fig. 6A, the first layer (i.e., the first low-voltage winding inner layer 1a) and the second layer (i.e., the first low-voltage winding outer layer 1b) of the first low-voltage winding are sleeved on the central core column of the transformer core 11 near the central core column and are located at the upper side in fig. 6A, and the first layer and the second layer of the first low-voltage winding are connected in series with each other to realize a first low-voltage system; the first layer (i.e., the second low-voltage winding inner layer 2a) and the second layer (i.e., the second low-voltage winding outer layer 2b) of the second low-voltage winding are sleeved on the central core column of the transformer core 11 near the central core column and are located at the lower side in fig. 6A, and the first layer and the second layer of the second low-voltage winding are connected in series with each other to realize a second low-voltage system.

As can be seen in fig. 6B, the upper half (i.e. the first high voltage winding 3a) and the lower half (i.e. the second high voltage winding 3B) of the high voltage winding are nested on the central core leg and may for example be located radially outside with respect to the first low voltage winding and the second low voltage winding, respectively, said upper and lower halves of the high voltage winding being connected in parallel with each other to realize a high voltage system.

As can be seen from fig. 6C, the upper half portion (i.e., the first high-voltage regulating winding 4a) and the lower half portion (i.e., the second high-voltage regulating winding 4b) of the high-voltage regulating winding are sleeved on the central core column and located at the outermost side in the radial direction thereof, and the upper half portion and the lower half portion of the high-voltage regulating winding are connected in parallel with each other to implement a high-voltage regulating system; the first half (i.e. first low voltage regulating winding 5a) and the latter half (i.e. second low voltage regulating winding 5b) cover of low voltage regulating winding are located on the central stem and are located its radial outside, and the central axis along central stem is located the top of the first half of high voltage regulating winding and the below of the latter half of high voltage regulating winding respectively, and the first low voltage regulating system and the second regulating system are inserted into respectively to the first half and the latter half of low voltage regulating winding to realize required low voltage regulating function.

It can be seen that the generator transformer according to this exemplary embodiment of the present application is based on the conventional three-system generator transformer shown in fig. 1, and a first low voltage regulating winding 5a and a second low voltage regulating winding 5b are respectively added on the outer side of the central core column of the transformer core 11 for realizing the required low voltage regulating function. As shown in fig. 6C, for example, the first low voltage regulating winding 5a, the second low voltage regulating winding 5b, the first high voltage regulating winding 4a, and the second high voltage regulating winding 4b are wound around the central core column of the transformer core 11 in a cylindrical shape, and the first low voltage regulating winding 5a, the second low voltage regulating winding 5b, the first high voltage regulating winding 4a, and the second high voltage regulating winding 4b have the same cylindrical radius relative to the central axis of the central core column. In other words, the first and second low voltage regulating windings 5a and 5b and the first and second high voltage regulating windings 4a and 4b preferably have the same radial height (i.e., have the same radius) with respect to the central axis of the central core, and may be arranged in the following order in the top-down direction in fig. 6C: a first low-voltage regulating winding 5a, a first high-voltage regulating winding 4a, a second high-voltage regulating winding 4b and a second low-voltage regulating winding 5 b.

As shown in fig. 7, as an example of a core structure of a regulating transformer that can be used in the low voltage regulating system of the generator transformer of the present application, the low voltage excitation windings (i.e., the first and second low voltage excitation windings 7a and 7b) and the low voltage series windings (i.e., the first and second low voltage series windings 8a and 8b) of the two low voltage regulating systems shown in fig. 4 may be respectively sleeved on the regulating transformer core 12. The transformer core 12 may have a core structure including two core columns, wherein the first low-voltage excitation winding 7a and the first low-voltage series winding 8a may be sleeved on one core column of the transformer core 12 as the first winding W2 of the transformer, and the second low-voltage excitation winding 7b and the second low-voltage series winding 8b may be sleeved on another core column of the transformer core 12 as the second winding W3 of the transformer. The above-described regulating transformer core 12 has only two legs for winding the windings, and there is no yoke for forming only the magnetic circuit of the regulating transformer core 12 without winding any windings, such a core also being referred to in the art as an 2/0-type core.

Fig. 5 shows a schematic electrical schematic of a low voltage regulating switch module that may be used in the low voltage regulating system of the generator transformer shown in fig. 4. Similar to fig. 2, the low voltage regulating switch module is also a conventional mechanical on-load tap changer known in the art, and the basic structure thereof is substantially the same as that of fig. 2, and the main difference between the two is that in fig. 5, when the first low voltage regulating winding 5a, the first low voltage regulating switch module 6a (here, the first low voltage regulating winding 5a and the first low voltage regulating switch module 6a are taken as examples, and the second low voltage regulating winding 5b and the first low voltage regulating switch module 6b are taken as examples) in the generator transformer according to the exemplary embodiment of the present application are in operation, the head end (first end) of the first low voltage excitation winding 7a shown in fig. 4 may be connected to the second switch connector K2 in fig. 5, and the tail end (second end) of the first low voltage excitation winding 7a shown in fig. 4 may be connected to the outlet connector (or terminal) shown in the position above the first low voltage regulating switch module 6a shown in the dashed line in fig. 5 By electrically connecting the first low-voltage regulating switch module 6a (in particular, based on a tap selector provided therein) to different taps (voltage regulating taps) of the first low-voltage regulating winding 5a by selecting or switching different connection positions, the effective number of turns (or the number of operating turns) of the first low-voltage regulating winding 5a can be changed, and thereby the input voltage of the first low-voltage excitation winding 7a associated therewith can be changed, and accordingly, a desired low-voltage regulating function can be smoothly realized by means of a voltage change of the first low-voltage series winding 8a which is connected in series to the first low-voltage winding.

Incidentally, similarly to fig. 2, the electrical schematic shown in fig. 5 is again only schematic, wherein the number of tap-changing taps of the low-voltage regulating winding (and the corresponding number of tap selectors) shown and the number of tap-changing taps in the low-voltage regulating system shown in fig. 4 are not schematic and do not correspond exactly. In fact, the number of low-voltage regulation taps and the corresponding regulation stages can be freely chosen according to the actual conditions.

Furthermore, the low voltage regulating function of the generator transformer of the present application can be realized by means of the following ways:

according to the present application, the number of turns of each low voltage regulating winding in fig. 4 can be set, for example, to be N times the minimum number of turns of the low voltage series winding (i.e., the so-called calculated number of turns or the designed number of turns) required to achieve a predetermined low voltage regulating purpose (e.g., a predetermined regulating ratio or degree), where N is theoretically an integer greater than 1. In other words, in the present application, for example, the ratio of the number of turns of each low voltage regulating winding to the minimum number of turns of the low voltage series winding required for achieving the predetermined low voltage regulating purpose may be set to N: 1. further, taking the first low-voltage excitation winding 7a and the first low-voltage series winding 8a as an example, assuming that the number of turns of the first low-voltage excitation winding 7a is T1 and the number of turns of the first low-voltage series winding 8a is T2, the first low-voltage excitation winding 7a and the first low-voltage series winding 8a may be designed such that the following relation is satisfied between the number of turns of the first low-voltage excitation winding 7a and the number of turns of the first low-voltage series winding 8 a: T1/T2 ═ N, where N is an integer greater than 1. In an exemplary embodiment of the present application, N may be equal to 6, for example, but is obviously not limited thereto. In this case, the current of the low voltage regulating winding shown in fig. 4 can be reduced by N times according to the principle of electromagnetic induction, while its voltage is increased by N times. In addition, by connecting the low-voltage regulating winding wound on the transformer core and the low-voltage excitation winding as a part of the low-voltage regulating system through the low-voltage regulating switch module and setting the ratio of the number of turns of the low-voltage excitation winding to the number of turns of the low-voltage series winding to be N times (i.e., the ratio of the number of turns of the low-voltage excitation winding to the number of turns of the low-voltage series winding is also set to be N: 1), the voltage of the low-voltage series winding can be reduced by N times relative to the low-voltage excitation winding, but the current thereof is consistent with the low-voltage current of the low-voltage winding in fig. 4, thereby enabling reliable series connection of the low-voltage series winding in a simple manner. In addition, under the control of the low-voltage regulating switch module, the voltage input at two ends of the low-voltage excitation winding can be changed by changing the number of turns of the low-voltage regulating winding, so that different magnetic fluxes are induced in an iron core magnetic circuit of a newly-added voltage regulating transformer, different voltage values are correspondingly induced in the low-voltage series winding, and the low-voltage excitation winding are connected in series, so that the low-voltage can be conveniently regulated, and the required low-voltage regulating function can be smoothly realized in a variable magnetic flux mode.

Therefore, under the condition that the structure of the existing generator transformer does not need to be changed remarkably, the required variable magnetic flux function is provided by additionally arranging the voltage regulating transformer, and the related low-voltage regulating winding, the low-voltage regulating switch module, the low-voltage excitation winding and the low-voltage series winding are introduced into the corresponding low-voltage system according to the requirement, so that different tap voltages can be selectively taken out from the low-voltage regulating winding under the control of the low-voltage regulating switch module, different voltage values can be obtained from the low-voltage series winding through the electromagnetic coupling effect between the corresponding low-voltage excitation winding and the low-voltage series winding, and the different voltage values are connected into the corresponding low-voltage winding in series, and the required low-voltage regulating function can be smoothly realized in a variable magnetic flux mode. In other words, the generator transformer can skillfully realize the required low-voltage regulation function in a variable magnetic flux mode reliably and conveniently, and therefore, the generator transformer with the voltage regulation function can be provided for both the low-voltage system at the low-voltage side and the high-voltage system at the high-voltage side. In addition, the device has the advantages of simple structure, convenience in use, low manufacturing cost and the like.

The technical solution of the present application is exemplarily described above mainly by taking a three-system generator transformer as an example. It is to be understood that both the foregoing embodiments and the related descriptions are exemplary and explanatory only and are not restrictive of the invention as claimed. For example, the solution of the present application (in particular the low voltage regulation system and its operating principle) may be applied not only to three-system generator transformers, but also to other types of generator transformers, such as dual-system generator transformers, and even to other kinds of transformers that also have low voltage regulation requirements. Furthermore, the present application is not only applicable to single-phase generator transformers, but also to three-phase generator transformers. Further, the present application can be advantageously applied to a power generation transformer having a wind power generator as a power supply source, but it is obviously not limited thereto.

In addition, in the above exemplary embodiment, the core of the voltage regulating transformer in the low voltage regulating system adopts an integrated core structure. As a variant or alternative, the core of the regulating transformer can also be divided into two separate core structures, for example. For example, the regulating transformer iron core includes first iron core and second iron core, first iron core with the second iron core is independent each other, first iron core adopts the shell type structure including a central stem and two other chokes, first low pressure excitation winding with first low pressure series connection winding all twine in on the central stem of first iron core, the second iron core adopts the shell type structure including a central stem and two other chokes, second low pressure excitation winding with second low pressure series connection winding all twine in on the central stem of second iron core. By means of the mode, excitation of different voltages can be achieved through the two independent magnetic circuits, different output voltages are generated, and therefore asynchronous low-voltage regulation of the two low-voltage systems can be achieved.

Further, it is to be understood that, for the sake of brevity, the description of the present application and the drawings thereof will focus on or show matters related to the improvement points or improvements of the present application, and the structures of other parts and related descriptions will be omitted or simplified. Details of the specific structure, connection relation, etc. of these omitted parts may be appropriately selected by those skilled in the art according to the existing knowledge in the field and the specific application, and will not be described herein.

In summary, the present application relates to a generator transformer, and more particularly, to a generator transformer having voltage regulation functions on both high-voltage side and low-voltage side, which includes a low-voltage regulation winding, a low-voltage regulation switch module, a low-voltage excitation winding, a low-voltage series winding, and a corresponding voltage regulation transformer. The generator transformer has the advantages that the regulating transformer is additionally arranged on the basis of the existing generator transformer to provide the required variable magnetic flux function, and the low-voltage regulating winding, the low-voltage regulating switch module, the low-voltage excitation winding and the low-voltage series winding which are related to the regulating transformer are correspondingly introduced, so that the required low-voltage regulating function can be smoothly realized in a variable magnetic flux mode under the control of the corresponding switch module, the generator transformer with the voltage regulating function on the high-voltage side and the low-voltage side can be provided in a simple and reliable mode, and the performances of the power quality stability and the like of a power system are obviously improved.

It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. A generator transformer, comprising:

a transformer core (11);

a low voltage winding wound on the transformer core (11), the low voltage winding being connected to an external generator to receive a power input from the external generator;

a high voltage winding wound around the transformer core (11), from which a voltage boosted by an electromagnetic induction principle is output;

the high-voltage regulating winding is wound on the transformer iron core (11); and

a high voltage regulating switch module (9) connecting the high voltage regulating winding and the high voltage winding in series,

the generator transformer is characterized by further comprising a low-voltage regulating winding, a low-voltage regulating switch module, a low-voltage exciting winding, a low-voltage series winding and a regulating transformer, wherein the regulating transformer comprises a regulating transformer iron core (12), the low-voltage regulating winding is wound on the transformer iron core (11), the low-voltage exciting winding is wound on the regulating transformer iron core (12) and serves as an input winding of the regulating transformer, the low-voltage series winding is wound on the regulating transformer iron core (12) and serves as an output winding of the regulating transformer, the first end of the low-voltage regulating winding is connected with the first end of the low-voltage exciting winding, the second end of the low-voltage regulating winding is connected with the second end of the low-voltage exciting winding through the low-voltage regulating switch module, the number of turns of the low-voltage exciting winding is greater than that of the low-voltage series winding, the first end of the low-voltage winding is connected with one terminal of the external generator, the second end of the low-voltage winding is connected with the first end of the low-voltage series winding, and the second end of the low-voltage series winding is connected with the other terminal of the external generator, so that a current flowing path flowing into the low-voltage winding from the first end of the low-voltage winding and flowing through the low-voltage winding and the low-voltage series winding and then flowing out of the second end of the low-voltage series winding is provided.

2. A generator transformer according to claim 1, characterised in that the low voltage tap changer module is a mechanical on-load tap changer, the low voltage tap winding is provided with a plurality of taps, a tap selector is provided in the mechanical on-load tap changer, and during operation of the generator transformer, the tap selector is connected to one of the plurality of taps based on switching of the tap selector between different connection positions, thereby changing the effective number of turns of the low voltage tap winding.

3. Generator transformer according to claim 1, wherein said transformer core is of shell-type construction comprising a central core leg and two side yokes, said low voltage winding, said high voltage regulating winding and said low voltage regulating winding being wound around said central core leg of said transformer core.

4. Generator transformer according to claim 3, wherein the high voltage regulation winding and the low voltage regulation winding are wound in a cylindrical shape on a central core leg of the transformer core, and wherein the high voltage regulation winding and the low voltage regulation winding have the same cylindrical radius with respect to a central axis of the central core leg.

5. Generator transformer according to any one of claims 1-4,

the low-voltage winding comprises a first low-voltage winding and a second low-voltage winding, the generator transformer correspondingly comprises a first low-voltage regulating winding (5a), a first low-voltage regulating switch module (6a), a first low-voltage exciting winding (7a), a first low-voltage series winding (8a), a second low-voltage regulating winding (5b), a second low-voltage regulating switch module (6b), a second low-voltage exciting winding (7b) and a second low-voltage series winding (8b),

the first end of first low pressure regulating winding (5a) with the first end of first low pressure excitation winding (7a) links to each other, the second end of first low pressure regulating winding (5a) via first low pressure regulating switch module (6a) with the second end of first low pressure excitation winding (7a) links to each other, the number of turns of first low pressure excitation winding (7a) is greater than the number of turns of first low pressure series winding (8a), the first end of first low pressure winding with a terminal of external generator links to each other, the second end of first low pressure winding with the first end of first low pressure series winding (8a) links to each other, the second end of first low pressure series winding (8a) with another terminal of external generator links to each other, thereby provides from the first end of first low pressure winding flows in and flows through first low pressure winding, A current flow path flowing from a second end of the first low voltage series winding (8a) after the first low voltage series winding (8a),

the first end of second low pressure regulating winding (5b) with the first end of second low pressure excitation winding (7b) links to each other, the second end of second low pressure regulating winding (5b) via second low pressure regulating switch module (6b) with the second end of second low pressure excitation winding (7b) links to each other, the number of turns of second low pressure excitation winding (7b) is greater than the number of turns of second low pressure series winding (8b), the first end of second low pressure winding links to each other with a terminal of another external generator, the second end of second low pressure winding with the first end of second low pressure series winding (8b) links to each other, the second end of second low pressure series winding (8b) with another terminal of another external generator links to each other, thereby provides from the first end of second low pressure winding flows in and flows through the second low pressure winding, A current flow path from a second end of the second low voltage series winding (8b) after the second low voltage series winding (8 b).

6. Generator transformer according to claim 5, wherein the regulating transformer core (12) is of a core type structure comprising two core legs, the first low voltage excitation winding (7a) and the first low voltage series winding (8a) are wound on one core leg of the regulating transformer core (12), and the second low voltage excitation winding (7b) and the second low voltage series winding (8b) are wound on the other core leg of the regulating transformer core (12).

7. Generator transformer according to claim 5, characterized in that the regulating transformer core (12) comprises a first core and a second core, the first core and the second core are independent of each other, the first core adopts a shell structure comprising one central core column and two side yokes, the first low voltage excitation winding (7a) and the first low voltage series winding (8a) are all wound on the central core column of the first core, the second core adopts a shell structure comprising one central core column and two side yokes, the second low voltage excitation winding (7b) and the second low voltage series winding (8b) are all wound on the central core column of the second core.

8. Generator transformer according to any of claims 1-4, wherein, assuming that the number of turns of the low voltage excitation winding is T1 and the number of turns of the low voltage series winding is T2, the following relation is satisfied between the number of turns of the low voltage excitation winding and the number of turns of the low voltage series winding:

T1/T2 ═ N, where N is an integer greater than 1.

9. Generator transformer according to claim 8, wherein N is equal to 6.

10. Generator transformer according to any of claims 1-4, wherein the generator transformer is a single-phase generator transformer or a three-phase generator transformer.

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