Generator transformer

Abstract

The present application relates to generator transformer, especially provides a kind of generator transformer with voltage regulating function in high voltage side and low voltage side, it includes: transformer core;Low voltage winding, high voltage winding and high voltage voltage regulating winding wound on transformer core;High voltage voltage regulating switch module for connecting high voltage voltage regulating winding with high voltage winding in series;And the low voltage voltage regulating winding, low voltage voltage regulating switch module, low voltage excitation winding, low voltage series winding and voltage regulating transformer required for realizing predetermined low voltage voltage regulating purpose.This application provides the required variable flux function by adding voltage regulating transformer on the basis of existing generator transformer, and correspondingly introduce the low voltage voltage regulating winding, low voltage voltage regulating switch module, low voltage excitation winding and low voltage series winding related therewith, whereby low voltage voltage regulating function can be smoothly realized in the mode of variable flux under the control of corresponding switch module, and the performance such as power quality stability of power system is significantly improved.

Description

Technical Field

[0001] This application relates to the field of transformers, and in particular to a generator transformer that has voltage regulation function on both the high-voltage and low-voltage sides. Background Technology

[0002] Generator transformers are known in the art, wherein, under normal circumstances, on one side of the generator transformer (low-voltage side or input side), at least one generator is connected to the low-voltage winding of the generator transformer (which belongs to the low-voltage system) as a power input; on the other side of the generator transformer (high-voltage side or output side), a voltage increased by the principle of electromagnetic induction is output from the high-voltage winding of the generator transformer (which belongs to the high-voltage system), for example, and connected to the power grid.

[0003] As a typical example of the aforementioned generator transformers, the three-system generator transformer, comprising two low-voltage systems and one high-voltage system, is gradually gaining wider application in this field. Under normal operating conditions, the low-voltage side of this three-system generator transformer is connected to two power sources (i.e., the first generator and the second generator), and correspondingly, two low-voltage systems exist. The first generator is connected to the first low-voltage system as the first power input, and the second generator is connected to the second low-voltage system as the second power input.

[0004] Traditional three-system generator transformers typically only have voltage regulation capabilities on the high-voltage side (or the high-voltage system), while the low-voltage side (the two low-voltage systems) usually maintains a constant voltage. This is clearly insufficient for operating conditions or situations where voltage regulation is also required for the low-voltage systems. Furthermore, for example, when a wind turbine operating on a wind power generation model is used as the power supply for this three-system generator transformer, the power supply side typically exhibits poor energy stability, meaning the voltage fluctuations on the generator side are significant. This negatively impacts the continuity and quality of power supply.

[0005] Based on the above background, there is a higher or newer demand for generator transformers to have voltage regulation functions on both the high-voltage and low-voltage sides, so as to at least partially overcome or eliminate the deficiencies or defects in the existing technologies and further improve the power quality stability and other performance of the power system. Summary of the Invention

[0006] In view of this, this application proposes a generator transformer, comprising:

[0007] Transformer core;

[0008] A low-voltage winding is wound around the transformer core, and the low-voltage winding is connected to an external generator to receive power input from the external generator;

[0009] The voltage, which is increased by the principle of electromagnetic induction, is output from the high-voltage winding wound around the transformer core.

[0010] The high-voltage regulating winding wound around the transformer core; and

[0011] A high-voltage regulating switch module that connects the high-voltage regulating winding in series with the high-voltage winding.

[0012] The generator transformer further includes 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. The regulating transformer includes a regulating transformer core. The low-voltage regulating winding is wound around the transformer core. The low-voltage excitation winding is wound around the regulating transformer core and serves as the input winding of the regulating transformer. The low-voltage series winding is wound around the regulating transformer core and serves as the output winding of the regulating transformer. The first end of the low-voltage regulating winding is connected to the first end of the low-voltage excitation winding. The second end is connected to the second end of the low-voltage excitation winding via the low-voltage regulating switch module. The number of turns of the low-voltage excitation winding is greater than the number of turns of the low-voltage series winding. The first end of the low-voltage winding is connected to one terminal of the external generator. The second end of the low-voltage winding is connected to the first end of the low-voltage series winding. The second end of the low-voltage series winding is connected to the other terminal of the external generator, thereby providing a current flow path from the first end of the low-voltage winding into the low-voltage winding, through the low-voltage winding and the low-voltage series winding, and out of the second end of the low-voltage series winding.

[0013] According to one feasible implementation, the low-voltage regulating switch module is a mechanical on-load tap changer. The low-voltage regulating winding is provided with multiple taps. The mechanical on-load tap changer is provided with a tap selector. During the operation of the generator transformer, based on the switching of the tap selector between different connection positions, the tap selector is connected to one of the multiple taps, thereby changing the effective number of turns of the low-voltage regulating winding.

[0014] According to one feasible implementation, the transformer core adopts a shell structure including a central core column and two side yokes, and the low-voltage winding, the high-voltage winding, the high-voltage regulating winding and the low-voltage regulating winding are all wound on the central core column of the transformer core.

[0015] According to one feasible implementation, both the high-voltage regulating winding and the low-voltage regulating winding are wound in a cylindrical shape around the central core of the transformer core, and the high-voltage regulating winding and the low-voltage regulating winding have the same cylindrical radius relative to the central axis of the central core.

[0016] According to one feasible implementation, the low-voltage winding includes a first low-voltage winding and a second low-voltage winding. Correspondingly, the generator transformer includes a first low-voltage regulating winding, a first low-voltage regulating switch module, a first low-voltage excitation 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 excitation winding, and a second low-voltage series winding. A first end of the first low-voltage regulating winding is connected to a first end of the first low-voltage excitation winding. A second end of the first low-voltage regulating winding is connected to a second end of the first low-voltage excitation winding via the first low-voltage regulating switch module. The number of turns in the first low-voltage excitation winding is greater than the number of turns in the first low-voltage series winding. A first end of the first low-voltage winding is connected to one terminal of the external generator. A second end of the first low-voltage winding is connected to a first end of the first low-voltage series winding. A second end of the first low-voltage series winding is connected to another terminal of the external generator, thereby providing... A current flow path is provided whereby current flows into the first end of the first low-voltage winding, passes through the first low-voltage winding and the first low-voltage series winding, and then flows out from the second end of the first low-voltage series winding; the first end of the second low-voltage regulating winding is connected to the first end of the second low-voltage excitation winding, and the second end of the second low-voltage regulating winding is connected to the second end of the second low-voltage excitation winding via the second low-voltage regulating switch module; the number of turns of the second low-voltage excitation winding is greater than the number of turns of the second low-voltage series winding; 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; and the second end of the second low-voltage series winding is connected to another terminal of the other external generator, thereby providing a current flow path whereby current flows into the first end of the second low-voltage winding, passes through the second low-voltage winding and the second low-voltage series winding, and then flows out from the second end of the second low-voltage series winding.

[0017] According to one feasible implementation, the core of the voltage regulating transformer adopts a core-type structure including two core columns. The first low-voltage excitation winding and the first low-voltage series winding are both wound on one core column of the voltage regulating transformer core, and the second low-voltage excitation winding and the second low-voltage series winding are both wound on the other core column of the voltage regulating transformer core.

[0018] According to one feasible implementation, the voltage regulating transformer core includes a first core and a second core, which are independent of each other. The first core adopts a shell structure including a central core column and two side yokes. The first low-voltage excitation winding and the first low-voltage series winding are both wound on the central core column of the first core. The second core adopts a shell structure including a central core column and two side yokes. The second low-voltage excitation winding and the second low-voltage series winding are both wound on the central core column of the second core.

[0019] According to one feasible implementation, assuming that the number of turns of the low-voltage excitation winding is T1 and the corresponding number of turns of the low-voltage series winding is T2, then the number of turns of the low-voltage excitation winding and the number of turns of the low-voltage series winding satisfy the following relationship: T1 / T2 = N, where N is an integer greater than 1.

[0020] According to one feasible implementation, N equals 6.

[0021] According to one feasible implementation, the generator transformer is a single-phase generator transformer or a three-phase generator transformer.

[0022] As can be seen from the above scheme, this application provides the required variable flux function by adding a voltage regulating transformer to the existing generator transformer, and correspondingly introducing a low-voltage regulating winding, a low-voltage regulating switch module, a low-voltage excitation winding, and a low-voltage series winding. Thus, under the control of the corresponding switch module, the predetermined low-voltage regulating function can be smoothly realized by changing the magnetic flux. This provides a generator transformer with voltage regulation function on both the high-voltage and low-voltage sides in a simple and reliable manner, thereby overcoming the deficiencies or defects in the prior art and significantly improving the power quality stability and other performance of the power system. Attached Figure Description

[0023] Preferred embodiments of this application will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can more clearly understand the above and other features and advantages of this application, in which:

[0024] Figure 1 This is a typical schematic wiring diagram of a traditional three-system generator transformer with voltage regulation function on the high-voltage side.

[0025] Figure 2 For can Figure 1 The diagram shows a schematic electrical schematic of the switching module used in the high-voltage regulation system of the three-system generator transformer.

[0026] Figure 3 for Figure 1The diagram shows a typical core structure and related winding configuration of a three-system generator transformer.

[0027] Figure 4 This is a schematic wiring diagram of a generator transformer according to an exemplary embodiment of this application.

[0028] Figure 5 For can Figure 4 The diagram shows the electrical schematic of the switching module used in the low-voltage regulating system of the generator transformer.

[0029] Figures 6A-6C for Figure 4 The diagram shows the core structure of the generator transformer and its related winding configuration.

[0030] Figure 7 For can Figure 4 The diagram shows a typical core structure and related winding configuration of a voltage regulating transformer used in a low-voltage voltage regulating system of a generator transformer.

[0031] Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of this application is provided by way of example with reference to embodiments and accompanying drawings.

[0033] It should be understood that the embodiments and related descriptions given below are exemplary and do not constitute a limitation of this application. Furthermore, it should be noted that in different drawings, the same reference numerals denote substantially the same or similar parts to avoid repetitive descriptions as much as possible. In addition, the dimensions, positions, etc., of the parts in the drawings are not strictly drawn to scale, and the dimensions and proportional relationships of the parts should not be considered as limitations of this application.

[0034] Before describing the technical solution of this application in detail, we will first briefly describe the electrical connection method and voltage regulation principle of the traditional three-system generator, which is a typical representative of generator transformer.

[0035] Figure 1 A typical schematic wiring diagram of a traditional three-system generator transformer with voltage regulation function on the high-voltage side is shown. It should be noted that, for the sake of simplicity, Figure 1 The wiring diagram is illustrated using a single-phase three-system generator transformer as an example. The wiring method for a three-phase three-system generator transformer is basically similar, except that the number of phases changes from single-phase to three-phase.

[0036] like Figure 1As shown, this three-system generator transformer typically includes two low-voltage windings on the low-voltage side: a first low-voltage winding and a second low-voltage winding. The first and second low-voltage windings are the main components of the two low-voltage systems (i.e., the first low-voltage system and the second low-voltage system), respectively. The first low-voltage winding can, for example, adopt a double-layer structure, comprising an inner layer 1a and an outer layer 1b. The inner and outer layers 1a and 1b are connected in series, and as shown... Figure 1 As shown, the upper part is connected to an external generator via the first low-voltage winding's start end LH1 and end end LE1. The second low-voltage winding can also be a double-layer structure, comprising an inner layer 2a and an outer layer 2b, connected in series, as shown... Figure 1 As shown, the lower part is connected to another external generator through the first end LH2 and the last end LE2 of the second low-voltage winding.

[0037] In addition, such as Figure 1 As shown, as an important component of its high-voltage system, the three-system generator transformer has a high-voltage winding on the high-voltage side, and in order to meet the usage requirements of voltage regulation function on the high-voltage side, the three-system generator transformer is usually also equipped with a high-voltage regulating winding, which is part of the high-voltage regulating system.

[0038] More specifically, such as Figure 1As shown, due to the presence of a low-voltage system and the entire high-voltage system in a semi-crossing operation condition in this type of three-system generator transformer, in order to reduce the circulating current in the high-voltage system under this magnetic field asymmetry operation condition, the three-system generator transformer typically includes two high-voltage windings on the high-voltage side, namely the first high-voltage winding 3a and the second high-voltage winding 3b, and correspondingly includes two high-voltage regulating windings, namely the first high-voltage regulating winding 4a and the second high-voltage regulating winding 4b. The first high-voltage winding 3a and the second high-voltage winding 3b typically adopt an upper and lower two-part (two halves) structure design, and the upper and lower parts (i.e., the first high-voltage winding 3a and the second high-voltage winding 3b) are connected in parallel. The first high-voltage regulating winding 4a and the second high-voltage regulating winding 4b can also typically adopt an upper and lower two-part (two halves) structure design, and the upper and lower parts (i.e., the first high-voltage regulating winding 4a and the second high-voltage regulating winding 4b) are connected in parallel. The intermediate tap between the first high-voltage winding 3a and the second high-voltage winding 3b is led out through the beginning 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 together to the beginning end (first end) of the high-voltage regulating switch module 9. The tail end (second end) of the high-voltage regulating switch module 9 is led out through the tail end connector HE. By selecting or switching different connection positions through the high-voltage regulating switch module 9 (in particular, based on the tap selector provided in the high-voltage regulating switch module 9) and electrically connecting it with different regulating taps (tap connectors) of the first high-voltage regulating winding 4a or the second high-voltage regulating winding 4b, the required high-voltage regulating function can be achieved. As an example, Figure 1 The high-voltage regulating system in the diagram is shown as having 4 regulating stages with 5 (i.e., 4+1) regulating taps, but in practice, the number of regulating stages can be designed to be any integer greater than 1, depending on specific requirements.

[0039] Figure 2 It shows that it can be used Figure 1 The diagram shows a schematic electrical schematic of the high-voltage regulating switch module used in the high-voltage regulating system of the three-system generator transformer. Figure 2 As shown, the high-voltage regulating switch module 9 can adopt a traditional mechanical on-load tap changer known in the art, which has the advantages of simple structure and low cost. The specific structure, circuit composition and working principle of the mechanical on-load tap changer are known in the art, and only need to be selectively applied. Therefore, detailed descriptions related to it are omitted in this article.

[0040] Combination Figure 2 As can be seen, taking one of the high-voltage windings, namely the first high-voltage winding 3a, as an example, when the high-voltage regulating system in the generator transformer of the above three systems is working, the tail end of the first high-voltage winding 3a can be connected to... Figure 2The first switch connector K1 is connected to the first high-voltage regulating winding 4a. Through the selection or switching of different connection positions by the high-voltage regulating switch module 9 (especially based on the tap selector installed therein), different numbers of turns of the first high-voltage regulating winding 4a can be connected in series with the first high-voltage winding 3a, thus realizing the series connection of different numbers of turns of the high-voltage regulating winding. Then, through the relevant connectors or terminals of the high-voltage regulating switch module 9 (such as…),… Figure 2 By leading out the connector shown in the upper right corner, the required high-voltage regulation function can be successfully achieved.

[0041] It should be noted that, for the sake of simplicity, Figure 2 The electrical schematic shown is for illustrative purposes only. The number of taps (and corresponding tap selectors) of the high-voltage regulating winding shown are not identical to the actual number of taps. Figure 1 The number of voltage regulating taps in the high-voltage voltage regulating system shown is not entirely consistent. In fact, as mentioned earlier, the number of voltage regulating taps and the corresponding voltage regulating stages can be freely selected according to the actual situation.

[0042] Figure 3 schematically shown Figure 1 The diagram shows a typical core structure and related winding configuration of a three-system generator transformer. For example... Figure 3 As shown, the transformer core 11 adopts a shell structure including a central core column and two side yokes. The two low-voltage windings, the two high-voltage windings, and the two high-voltage regulating windings (collectively referred to as the transformer main windings W1) are all wound (or sleeved) on the central core column of the transformer core 11. No windings are wound on the two side yokes of the transformer core 11. They are only used to form the magnetic circuit of the transformer core 11. This type of core is also referred to in the art as a 1 / 2 type core.

[0043] As mentioned earlier, the traditional three-system generator transformer only has a voltage regulation function on the high-voltage side (i.e., it has a high-voltage regulating winding and is part of the high-voltage regulating system), which obviously cannot adapt to situations or operating conditions where there is a need for voltage regulation on both the high-voltage and low-voltage sides.

[0044] Recognizing the defects or deficiencies in the existing technologies, the inventors of this application have proposed a novel technical solution that provides a generator transformer with voltage regulation functions on both the high-voltage and low-voltage sides (i.e., the high-voltage system and the low-voltage system).

[0045] In particular, according to an exemplary embodiment of this application, a generator transformer with voltage regulation function on both the high-voltage side and the low-voltage side (i.e., the high-voltage system and the low-voltage system) is provided, which can... Figure 1It is an improvement on the traditional three-system generator-transformer shown.

[0046] The following is combined with Figures 4-7 A generator transformer according to an exemplary embodiment of this application is described in detail to provide a clear understanding of the basic principles and structural design aspects of this application. It should be noted that, for ease of description, Figures 4-7 The exemplary embodiment is described using a three-system generator transformer with two low-voltage systems and one high-voltage system as an example, but this application is obviously not limited thereto.

[0047] first, Figure 4 A schematic wiring diagram of a generator transformer according to an exemplary embodiment of this application is shown.

[0048] like Figure 4 As shown, with Figure 1 Similarly, the generator transformer includes two low-voltage windings on the low-voltage side: a first low-voltage winding and a second low-voltage winding. The first low-voltage winding includes, for example, an inner layer 1a and an outer layer 1b, which may have a double-layer structure. The second low-voltage winding includes, for example, an inner layer 2a and an outer layer 2b, which may have a double-layer structure. Furthermore, with... Figure 1 Similarly, the generator transformer includes two high-voltage windings on the high-voltage side, namely a first high-voltage winding 3a and a second high-voltage winding 3b, and correspondingly includes two high-voltage regulating windings, namely a first high-voltage regulating winding 4a and a second high-voltage regulating winding 4b. 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 be adopted with... Figure 1 The wiring method is exactly the same, therefore its wiring method is... Figure 4 The details are omitted and will not be elaborated upon further.

[0049] In traditional generator transformers, due to the generally large current in the low-voltage system, conventional designs often cannot select suitable switches to achieve voltage regulation on the low-voltage side. To solve this problem, according to the exemplary technical solution of this application, a low-voltage regulating system is added to the aforementioned three-system generator transformer, and the required low-voltage regulating function is achieved by means of the added regulating transformer through flux variation.

[0050] More specifically, such as Figure 4 As shown, corresponding to the two low-voltage windings (i.e., the first low-voltage winding including the inner layer 1a and the outer layer 1b of the first low-voltage winding, and the second low-voltage winding including the inner layer 2a and the outer layer 2b of the second low-voltage winding), Figure 4The generator transformer also includes two low-voltage regulating systems: a first low-voltage regulating system and a second low-voltage regulating system. The first low-voltage regulating system includes 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 8a. The second low-voltage regulating system includes 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 8b. The first low-voltage regulating winding 5a and the second low-voltage regulating winding 5b can respectively serve as… Figure 3 A portion of the transformer main winding W1 shown is wound around the central core post of the transformer core 11, and is connected to 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 6b, respectively. The first low-voltage excitation winding 7a and the second low-voltage excitation winding 7b can be wound around the added voltage regulating transformer core, and each can be electromagnetically coupled to the first low-voltage series winding 8a and the second low-voltage series winding 8b, which are also wound around the added voltage regulating transformer core. The first low-voltage series winding 8a and the second low-voltage series winding 8b can be connected in series with the first low-voltage winding and the second low-voltage winding, respectively.

[0051] More specifically, for example, the first end of the first low-voltage regulating winding 5a is connected to the first end of the first low-voltage excitation winding, and the second end of the first low-voltage regulating winding 5a is connected to the 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 greater than the number of turns 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, and the second end of the first low-voltage winding is connected to the first end of the first low-voltage series winding 8a. The second end of the first low-voltage series winding 8a, i.e., the tail end AE1 (which can serve as the tail end of the first low-voltage regulating system), is connected to the other terminal of the external generator. This provides a current flow path from the first end of the first low-voltage winding into the first low-voltage winding, through the first low-voltage winding and the first low-voltage series winding 8a, and out from the second end of the first low-voltage series winding 8a.

[0052] Similarly, for example, the first end of the second low-voltage regulating winding 5b is connected to the first end of the second low-voltage excitation winding 7b, and the second end of the second low-voltage regulating winding 5b is connected to the 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 greater than the number of turns 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, and the second end of the second low-voltage winding is connected to the first end of the second low-voltage series winding 8b. The second end of the second low-voltage series winding 8b, i.e., the tail end AE2 (which can serve as the tail end of the second low-voltage regulating system), is connected to the other terminal of the other external generator. This provides a current flow path from the first end of the second low-voltage winding into the second low-voltage winding, through the second low-voltage winding, the second low-voltage series winding 8b, and out from the second end of the second low-voltage series winding 8b.

[0053] Figures 6A-6C The diagrams illustrate the points shown in the diagrams. Figure 4 The core structure and related winding configuration of the generator transformer shown provide a more intuitive understanding of its structural design.

[0054] from Figure 6A As can be seen, the first layer (i.e., the inner layer 1a) and the second layer (i.e., the outer layer 1b) of the first low-voltage winding are sleeved on the central core post of the transformer core 11 and located near the center core post. Figure 6A On the upper side of the transformer core 11, the first layer and the second layer of the first low-voltage winding are connected in series to form a first low-voltage system; the first layer (i.e., the inner layer 2a) and the second layer (i.e., the outer layer 2b) of the second low-voltage winding are sleeved on the central core post of the transformer core 11 and located near the central core post. Figure 6A On the lower side of the second low-voltage winding, the first and second layers are connected in series to realize the second low-voltage system.

[0055] from Figure 6B As can be seen, 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 sleeved on the central core column and, for example, can be located radially outside the first low-voltage winding and the second low-voltage winding, respectively. The upper half and the lower half of the high-voltage winding are connected in parallel to each other to realize the high-voltage system.

[0056] from Figure 6CAs can be seen, the upper half (i.e., the first high-voltage regulating winding 4a) and the lower half (i.e., the second high-voltage regulating winding 4b) of the high-voltage regulating winding are sleeved on the central core column and located on its radial outermost side. The upper half and the lower half of the high-voltage regulating winding are connected in parallel to realize the high-voltage regulating system. The upper half (i.e., the first low-voltage regulating winding 5a) and the lower half (i.e., the second low-voltage regulating winding 5b) of the low-voltage regulating winding are sleeved on the central core column and located on its radial outermost side. They are located above the upper half of the high-voltage regulating winding and below the lower half of the high-voltage regulating winding, respectively, along the central axis of the central core column. The upper half and the lower half of the low-voltage regulating winding are respectively connected to the first low-voltage regulating system and the second regulating system to realize the required low-voltage regulating function.

[0057] Therefore, it can be seen that the generator transformer according to this exemplary embodiment is... Figure 1 Based on the traditional three-system generator transformer shown, a first low-voltage regulating winding 5a and a second low-voltage regulating winding 5b are added to the outside of the central core column of the transformer core 11 to achieve the required low-voltage regulating function. Figure 6C As shown, 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 all wound in a cylindrical shape on the central core of the transformer core 11, 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. In other words, the first low-voltage regulating winding 5a and the second low-voltage regulating winding 5b preferably have the same radial height (i.e., the same radius) relative to the central axis of the central core, and can be wound along... Figure 6C The windings are arranged in the following order from top to bottom: first low-voltage regulating winding 5a, first high-voltage regulating winding 4a, second high-voltage regulating winding 4b, and second low-voltage regulating winding 5b.

[0058] like Figure 7 As shown, this is an example of the core structure of a voltage regulating transformer that can be used in the low-voltage voltage regulating system of the generator transformer of this application. Figure 4The low-voltage excitation windings (i.e., the first low-voltage excitation winding 7a and the second low-voltage excitation winding 7b) and the low-voltage series windings (i.e., the first low-voltage series winding 8a and the second low-voltage series winding 8b) of the two low-voltage regulating systems shown can be respectively sleeved on the core 12 of the regulating transformer. The core 12 of the regulating transformer can, for example, adopt a core-type structure including two core posts, wherein the first low-voltage excitation winding 7a and the first low-voltage series winding 8a together can serve as the first winding W2 of the regulating transformer and are sleeved on one core post of the regulating transformer core 12, and the second low-voltage excitation winding 7b and the second low-voltage series winding 8b together can serve as the second winding W3 of the regulating transformer and are sleeved on the other core post of the regulating transformer core 12. The aforementioned regulating transformer core 12 has only two core posts for winding; there is no yoke used only to form the magnetic circuit of the regulating transformer core 12 without winding any coils. This type of core is also referred to in the art as a 2 / 0 type core.

[0059] Figure 5 It shows that it can be used Figure 4 The diagram shows a schematic electrical schematic of the low-voltage regulating switch module used in the low-voltage regulating system of the generator transformer. Figure 2 Similarly, the low-voltage regulating switch module is also a conventional mechanical on-load tap changer known in the art, and its basic structure is the same as... Figure 2 They are largely the same; the main difference lies in... Figure 5 In the generator transformer according to the exemplary embodiment of this application, the first low-voltage regulating winding 5a and the first low-voltage regulating switch module 6a (taking the first low-voltage regulating winding 5a and the first low-voltage regulating switch module 6a as examples here, the working principle of the second low-voltage regulating winding 5b and the first low-voltage regulating switch module 6b is basically the same) are in operation. Figure 4 The first end (first end) of the first low-voltage excitation winding 7a shown can be connected to Figure 5 The second switch connector K2 is connected in the middle. Figure 4 The tail end (second end) of the first low-voltage excitation winding 7a shown can be connected to Figure 5 The lead-out connector (or terminal) shown above the first low-voltage regulating switch module 6a, indicated by the dashed box, is connected to the first low-voltage regulating winding 5a. By selecting or switching different connection positions through the first low-voltage regulating switch module 6a (in particular, based on the tap selector provided therein), the electrical connection with different taps (regulating taps) of the first low-voltage regulating winding 5a can be changed. This can change the effective number of turns (or working number of turns) of the first low-voltage regulating winding 5a, and thereby change the input voltage of the associated first low-voltage excitation winding 7a. The required low-voltage regulation function can be smoothly achieved by means of the voltage change of the first low-voltage series winding 8a connected in series with the first low-voltage winding.

[0060] Incidentally, similar toFigure 2 , Figure 5 The electrical schematic shown is also only illustrative, illustrating the number of taps on the low-voltage regulating winding (and the corresponding number of tap selectors) and Figure 4 The number of voltage regulating taps in the low-voltage regulating system shown is not illustrative and does not correspond exactly. In fact, the number of low-voltage regulating taps and the corresponding voltage regulating stages can be freely selected according to actual conditions.

[0061] Furthermore, the low-voltage regulation function of the generator transformer in this application can be achieved by means of the following method:

[0062] According to this application, for example, it can be Figure 4 The number of turns in each low-voltage regulating winding is set to N times the minimum number of turns in the low-voltage series winding (i.e., the so-called calculated number of turns or designed number of turns) required to achieve a predetermined low-voltage regulation purpose (e.g., a predetermined regulation ratio or degree), where theoretically N is an integer greater than 1. In other words, in this application, for example, the ratio of the number of turns in each low-voltage regulating winding to the minimum number of turns in the low-voltage series winding required to achieve the predetermined low-voltage regulation purpose can be set to N:1. Furthermore, taking the first low-voltage excitation winding 7a and the first low-voltage series winding 8a as examples, assuming the number of turns in the first low-voltage excitation winding 7a is T1 and the number of turns in the first low-voltage series winding 8a is T2, the first low-voltage excitation winding 7a and the first low-voltage series winding 8a can be designed such that the number of turns in the first low-voltage excitation winding 7a and the number of turns in the first low-voltage series winding 8a satisfy the following relationship: T1 / T2 = N, where N is an integer greater than 1. In the exemplary embodiments of this application, N can be equal to 6, for example, but is obviously not limited to this. In this case, according to the principle of electromagnetic induction, Figure 4 The current in the low-voltage regulating winding shown can be reduced by N times, while its voltage increases by N times. Furthermore, by connecting the low-voltage regulating winding wound on the transformer core to the low-voltage excitation winding, which is part of the low-voltage regulating system, via a low-voltage regulating switch module, and setting the ratio of the number of turns in the low-voltage excitation winding to the number of turns in the low-voltage series winding to be N times (i.e., the ratio of the number of turns in the low-voltage excitation winding to the number of turns in the low-voltage series winding is also set to N:1), the voltage of the low-voltage series winding can be reduced by N times relative to the low-voltage excitation winding, while its current increases by N times. Figure 4The low-voltage current is consistent with that of the low-voltage winding, thus enabling reliable connection of the low-voltage series winding in a simple manner. Furthermore, under the control of the low-voltage regulating switch module, by changing the number of turns connected to the low-voltage regulating winding, the voltage input across the low-voltage excitation winding can be altered. This induces different magnetic fluxes in the core magnetic circuit of the newly added voltage regulating transformer, correspondingly inducing different voltage values ​​in the low-voltage series winding. This voltage is then connected in series with the low-voltage winding in the transformer's main circuit, allowing for convenient adjustment of the low-voltage voltage. This enables the smooth realization of the required low-voltage regulation function through a variable magnetic flux method.

[0063] Therefore, this application, without significantly altering the structure of existing generator transformers, provides the required variable flux function by adding a voltage regulating transformer. It introduces relevant low-voltage regulating windings, low-voltage regulating switch modules, low-voltage excitation windings, and low-voltage series windings into the corresponding low-voltage systems as needed. Under the control of the low-voltage regulating switch module, different tap voltages can be selectively extracted from the low-voltage regulating windings. Then, through the electromagnetic coupling between the corresponding low-voltage excitation windings and low-voltage series windings, different voltage values ​​are obtained in the low-voltage series windings and connected in series with the corresponding low-voltage windings. This allows for the smooth realization of the required low-voltage regulation function through variable flux. In other words, this application ingeniously and reliably and conveniently achieves the required low-voltage regulation function through variable flux, thereby providing a generator transformer with voltage regulation functions on both the low-voltage side and the high-voltage side. Furthermore, this application has advantages such as simple structure, ease of use, and low manufacturing cost.

[0064] The above description, primarily using a three-system generator transformer as an example, exemplifies the technical solution of this application. Obviously, as mentioned above, the embodiments and related descriptions should be understood as exemplary and not constituting a limitation of this application. For example, the technical solution of this application (especially the low-voltage regulating system and its working principle) can 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 types of transformers with similar low-voltage regulating requirements. Furthermore, this application is not only applicable to single-phase generator transformers but also to three-phase generator transformers. In addition, this application can be advantageously applied to generator transformers powered by wind turbines, but it is clearly not limited thereto.

[0065] Furthermore, in the above exemplary embodiment, the core of the voltage regulating transformer in the low-voltage regulating system adopts an integral core structure. As a variation or alternative, the core of the voltage regulating transformer can also be divided into two independent core structures. For example, the voltage regulating transformer core includes a first core and a second core, which are independent of each other. The first core adopts a shell structure including a central core post and two side yokes. The first low-voltage excitation winding and the first low-voltage series winding are both wound on the central core post of the first core. The second core adopts a shell structure including a central core post and two side yokes. The second low-voltage excitation winding and the second low-voltage series winding are both wound on the central core post of the second core. By means of this, different voltage excitations can be achieved through two independent magnetic circuits, resulting in different output voltages, thereby enabling asynchronous low-voltage regulation of the two low-voltage systems.

[0066] Furthermore, it is understood that, for the sake of brevity, the specification and accompanying drawings of this application focus on describing or illustrating the improvements or improvements of this application, while omitting or simplifying the structure and related descriptions of other parts. Regarding the specific structure, connection relationships, and other details of these omitted parts, those skilled in the art can make appropriate selections based on existing knowledge in the field and specific applications, and will not be elaborated upon here.

[0067] In summary, this application relates to generator transformers, and particularly provides a generator transformer with voltage regulation functions on both the high-voltage and low-voltage sides. It includes a low-voltage regulating winding, a low-voltage regulating switch module, a low-voltage excitation winding, a low-voltage series winding, and a corresponding regulating transformer. This application adds a regulating transformer to an existing generator transformer to provide the required flux-changing function, and accordingly introduces the associated low-voltage regulating winding, low-voltage regulating switch module, low-voltage excitation winding, and low-voltage series winding. Thus, under the control of the corresponding switch module, the required low-voltage regulation function can be smoothly achieved through flux-changing. This provides a generator transformer with voltage regulation functions on both the high-voltage and low-voltage sides in a simple and reliable manner, and significantly improves the power quality stability and other performance characteristics of the power system.

[0068] It should be noted again that the above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A generator transformer, comprising: Transformer core (11); A low-voltage winding is wound around the transformer core (11), and the low-voltage winding is connected to an external generator to receive power input from the external generator; The voltage of the high-voltage winding wound around the transformer core (11) is increased by electromagnetic induction and output from the high-voltage winding. The high-voltage regulating winding wound around the transformer core (11); and The high voltage regulating switch module (9) is connected in series with the high voltage regulating winding. The generator transformer is characterized in that it further includes 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. The regulating transformer includes a regulating transformer core (12). The low-voltage regulating winding is wound around the transformer core (11). The low-voltage excitation winding is wound around the regulating transformer core (12) and serves as the input winding of the regulating transformer. The low-voltage series winding is wound around the regulating transformer core (12) and serves as the output winding of the regulating transformer. The first end of the low-voltage regulating winding is connected to the first end of the low-voltage excitation winding. The second end of the low-voltage regulating winding is connected to the second end of the low-voltage excitation winding via the low-voltage regulating switch module. The number of turns of the low-voltage excitation winding is greater than the number of turns of the low-voltage series winding. The first end of the low-voltage winding is connected to one terminal of the external generator. The second end of the low-voltage winding is connected to the first end of the low-voltage series winding. The second end of the low-voltage series winding is connected to the other terminal of the external generator, thereby providing a current flow path from the first end of the low-voltage winding into the low-voltage winding, through the low-voltage winding and the low-voltage series winding, and out from the second end of the low-voltage series winding.

2. The generator transformer according to claim 1, characterized in that, The low-voltage regulating switch module is a mechanical on-load tap changer. The low-voltage regulating winding is provided with multiple taps. The mechanical on-load tap changer is provided with a tap selector. During the operation of the generator transformer, based on the switching of the tap selector between different connection positions, the tap selector is connected to one of the multiple taps, thereby changing the effective number of turns of the low-voltage regulating winding.

3. The generator transformer according to claim 1, characterized in that, The transformer core adopts a shell structure including a central core column and two side yokes. The low-voltage winding, the high-voltage winding, the high-voltage regulating winding and the low-voltage regulating winding are all wound on the central core column of the transformer core.

4. The generator transformer according to claim 3, characterized in that, Both the high-voltage regulating winding and the low-voltage regulating winding are wound in a cylindrical shape around the central core of the transformer core, and the high-voltage regulating winding and the low-voltage regulating winding have the same cylindrical radius relative to the central axis of the central core.

5. The generator transformer according to any one of claims 1 to 4, characterized in that, The low-voltage winding includes a first low-voltage winding and a second low-voltage winding. The generator transformer correspondingly includes a first low-voltage regulating winding (5a), a first low-voltage regulating switch module (6a), a first low-voltage excitation 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 excitation winding (7b), and a second low-voltage series winding (8b). The first end of the first low-voltage regulating winding (5a) is connected to the first end of the first low-voltage excitation winding (7a). The second end of the first low-voltage regulating winding (5a) is connected to the 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 greater than the number of turns of the first low-voltage series winding (8a). The first end of the first low-voltage winding is connected to one terminal of the 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). The second end of the first low-voltage series winding (8a) is connected to the other terminal of the external generator. This provides a current flow path from the first end of the first low-voltage winding into the first low-voltage winding, through the first low-voltage winding and the first low-voltage series winding (8a), and out from the second end of the first low-voltage series winding (8a). The first end of the second low-voltage regulating winding (5b) is connected to the first end of the second low-voltage excitation winding (7b). The second end of the second low-voltage regulating winding (5b) is connected to the 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 greater than the number of turns 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). The second end of the second low-voltage series winding (8b) is connected to another terminal of the other external generator. This provides a current flow path from the first end of the second low-voltage winding into the second low-voltage winding, through the second low-voltage winding and the second low-voltage series winding (8b), and out of the second end of the second low-voltage series winding (8b).

6. The generator transformer according to claim 5, characterized in that, The core (12) of the voltage regulating transformer adopts a core structure including two core columns. The first low-voltage excitation winding (7a) and the first low-voltage series winding (8a) are both wound on one core column of the voltage regulating transformer core (12), and the second low-voltage excitation winding (7b) and the second low-voltage series winding (8b) are both wound on the other core column of the voltage regulating transformer core (12).

7. The generator transformer according to claim 5, characterized in that, The voltage regulating transformer core (12) includes 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 including a central core column and two side yokes. The first low-voltage excitation winding (7a) and the first low-voltage series winding (8a) are both wound on the central core column of the first core. The second core adopts a shell structure including a central core column and two side yokes. The second low-voltage excitation winding (7b) and the second low-voltage series winding (8b) are both wound on the central core column of the second core.

8. The generator transformer according to any one of claims 1 to 4, characterized in that, Assuming 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, then the number of turns of the low-voltage excitation winding and the number of turns of the low-voltage series winding satisfy the following relationship: T1 / T2 = N, where N is an integer greater than 1.

9. The generator transformer according to claim 8, characterized in that, N equals 6.

10. The generator transformer according to any one of claims 1 to 4, characterized in that, The generator transformer is either a single-phase generator transformer or a three-phase generator transformer.

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