Split phase-shifting transformer

Abstract

The invention discloses a split phase-shifting transformer, and particularly relates to the field of transformers, the split phase-shifting transformer comprises an excitation winding, a phase modulation winding, a high-voltage winding, a voltage regulation winding, an iron core and an oil tank, the excitation winding, the phase modulation winding, the high-voltage winding and the voltage regulation winding are sequentially arranged on the iron core in a sleeving manner; the excitation winding, the phase modulation winding, the high-voltage winding, the voltage regulation winding and the iron core are all arranged in the oil tank. The phase shifting function is added on the basis of the step-up or step-down function of a traditional low-voltage split transformer, the newly-added requirement that a line needs power flow regulation and control is met, the phase-shifting transformer of the structure is of a single-transformer-body structure, the number of windings is small, wiring is easy, and compared with a multi-transformer combined structure achieving the same function, cost is low, occupied space is small, and cost is low. Compared with a phase-shifting voltage-regulating transformer with a double-transformer-body structure, the phase-shifting voltage-regulating transformer has the advantages that the structure of the phase-shifting voltage-regulating transformer is greatly simplified, the design and manufacturing difficulty is reduced, and the operation reliability of a system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and more particularly to a split phase-shifting transformer. Background Art

[0002] Currently, the phase-shifting transformer used to regulate power flow distribution and power flow in power systems usually only changes the phase angle of the voltage and does not have the function of stepping up or down. It is necessary to combine the phase-shifting transformer with a conventional transformer to make it have not only the phase-shifting function but also the step-up or step-down function of the conventional transformer.

[0003] However, the combination of phase-shifting transformers and conventional transformers requires a large number of transformers. When the number of transformers increases, more wiring is required, which makes the wiring complex and space-consuming, increases the floor space, and increases the investment in related lines and switches, resulting in extremely high costs, as well as poor operational reliability and maintainability due to the complexity of the system. Summary of the invention

[0004] A split phase-shifting transformer provided by the present invention aims to solve the following problem: the existing method of combining a phase-shifting transformer with a conventional transformer requires a large number of transformers. When the number of transformers increases, more wiring is required, resulting in complex wiring and space. The floor space is increased, and the investment in related lines and switches is increased, resulting in extremely high costs, as well as poor operational reliability and maintainability due to the complexity of the system.

[0005] To achieve the above object, the present invention provides the following technical solutions: a split phase-shifting transformer, comprising: an excitation winding, a phase-adjusting winding, a high-voltage winding, a voltage-regulating winding, an iron core and an oil tank, wherein the excitation winding, the phase-adjusting winding, the high-voltage winding and the voltage-regulating winding are sequentially sleeved and arranged on the iron core, and the excitation winding, the phase-adjusting winding, the high-voltage winding, the voltage-regulating winding and the iron core are all placed in the oil tank;

[0006] The transformer is a three-phase structure. Three excitation windings are connected end to end to form a triangle connection. Each excitation winding is connected in series with two phase-adjusting windings. The three vertices of the triangle connection are respectively connected to the phase-adjusting windings of different phases. The two phase-adjusting windings are respectively connected to corresponding phase-adjusting switches. The three line ends of the phase-adjusting windings are respectively connected to the three phases of the low voltage.

[0007] The high-voltage side of the oil tank is provided with three high-voltage outlet terminals, which are respectively connected to the three phases of the high voltage. The high-voltage and low-voltage sides of the oil tank are both provided with three low-voltage outlet terminals. The low-voltage outlet terminals on the high-voltage side are respectively connected to the three low-voltage phases on the high-voltage side, and the low-voltage outlet terminals on the low-voltage side are respectively connected to the three low-voltage phases on the low-voltage side.

[0008] In a preferred embodiment, the connection between the two low-voltage sides is a delta-connected symmetrical phase-shifting structure, and the two line ends on the low-voltage side are connected through a phase-modulating winding.

[0009] In a preferred embodiment, the three-phase high-voltage winding and the voltage regulating winding are connected in a star shape, a voltage regulating switch is connected in series between the high-voltage winding and the voltage regulating winding, the three line ends of the high-voltage winding are respectively connected to the three phases on the high-voltage side, a high-voltage neutral point is provided at the corner of the low-voltage side of the oil tank, and the high-voltage neutral point is connected to the zero phase.

[0010] In a preferred embodiment, the transformer low voltage is a double-split structure, and the connection group between the high and low voltages is Yd-d. The low voltage winding of the transformer is divided into two parts, each part is connected to the two line ends of the high voltage winding, forming a Yd connection, d indicates that there is a phase difference between the high voltage winding and the low voltage winding.

[0011] In a preferred embodiment, the excitation winding is a single-branch end-outlet structure, which means that the excitation winding has only one line outgoing from the end of the winding and connected to the excitation power supply or control system.

[0012] In a preferred embodiment, the phase-modulating winding is a double U-shaped structure with upper and lower axial splits, which is used to control the phase difference of the current.

[0013] In a preferred embodiment, the high-voltage winding is a central outlet structure, and the wire of the high-voltage winding is outlet from the center of the winding, which is used to generate a magnetic field when the transformer is running.

[0014] In a preferred embodiment, the voltage regulating winding is a parallel structure of upper and lower branches, which is used to provide a larger current capacity and lower voltage fluctuation.

[0015] The beneficial effects of the present invention are:

[0016] The present invention solves the new demand for line flow control by adding a phase shifting function to the step-up or step-down function of a traditional low-voltage split transformer. The phase shifting transformer of this structure is a single-body structure with a small number of windings and simple wiring. It has lower cost and occupies less space than a combined structure of multiple transformers that achieve the same function. It does not require additional lines, switches or other additional devices. It is also much simpler than a double-body phase shifting and voltage regulating transformer, which reduces the difficulty of design and manufacturing and improves the reliability of system operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the top structure of the present invention.

[0018] Figure 2 It is a schematic diagram of the winding connection principle of the present invention.

[0019] Figure 3Schematic diagram of the winding arrangement of the present invention.

[0020] The accompanying drawings are marked as follows: 1. excitation winding; 2. phase-adjusting winding; 3. high-voltage winding; 4. voltage-regulating winding; 5. iron core; 6. high-voltage output terminal; 7. low-voltage output terminal; 8. high-voltage neutral point; 9. phase-adjusting switch; 10. voltage-regulating switch; 11. oil tank. DETAILED DESCRIPTION

[0021] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0022] Refer to the instruction manual Figures 1 to 3 A split phase-shifting transformer comprises: an excitation winding 1, a phase-adjusting winding 2, a high-voltage winding 3, a voltage-regulating winding 4, an iron core 5 and an oil tank 11, wherein the excitation winding 1, the phase-adjusting winding 2, the high-voltage winding 3, and the voltage-regulating winding 4 are sequentially sleeved and arranged on the iron core 5, and the excitation winding 1, the phase-adjusting winding 2, the high-voltage winding 3, the voltage-regulating winding 4 and the iron core 5 are all placed in the oil tank 11;

[0023] The transformer is a three-phase structure. Three excitation windings 1 are connected end to end to form a triangle connection. Each excitation winding 1 is connected in series with two phase-adjusting windings 2. The three vertices of the triangle connection are respectively connected to the phase-adjusting windings 2 of different phases. The two phase-adjusting windings 2 are respectively connected to corresponding phase-adjusting switches 9. The three line ends of the phase-adjusting windings 2 are respectively connected to the three phases of the low voltage.

[0024] The high-voltage three-phase includes phases A, B, and C, the high-voltage side low-voltage three-phase includes phases a1, b1, and c1, and the low-voltage side low-voltage three-phase includes phases a2, b2, and c2;

[0025] The high-voltage side of the oil tank 11 is provided with three high-voltage outlet terminals 6, which are respectively connected to the three phases of the high voltage. The high-voltage side and the low-voltage side of the oil tank 11 are both provided with three low-voltage outlet terminals 7. The low-voltage outlet terminals 7 on the high-voltage side are respectively connected to the three low-voltage phases on the high-voltage side, and the low-voltage outlet terminals 7 on the low-voltage side are respectively connected to the three low-voltage phases on the low-voltage side.

[0026] It should be noted that the transformer has a three-phase structure, each phase includes an excitation winding 1, two phase-adjusting windings 2, a high-voltage winding 3 and a voltage-adjusting winding 4, with a total of fifteen windings. The high-voltage three-phase includes phases A, B, and C, the high-voltage three-phase includes phases a1, b1, and c1, and the low-voltage three-phase includes phases a2, b2, and c2. By arranging the excitation winding 1 and the phase-adjusting winding 2 on the core, this layout can effectively reduce the magnetic resistance and improve the efficiency of the transformer. By placing the excitation winding 1 and the phase-adjusting winding 2 close to the core 5, the transfer path of the magnetic field is shorter, the magnetic resistance loss is reduced, and the energy transmission efficiency is improved. By connecting the three excitation windings 1 end to end to form a triangle connection, each excitation winding Group 1 connects two phase-adjusting windings 2 in series to realize the function of an autotransformer. The autotransformer can realize current conversion while converting voltage, thereby meeting the power transmission requirements under different load conditions. By connecting the line end of the phase-adjusting winding 2 to the low-voltage three-phase, the voltage on the low-voltage side can be regulated and controlled. The existence of the phase-adjusting winding 2 enables the transformer to adapt to the voltage requirements under different load conditions and provide a stable output voltage. The high-voltage side and the low-voltage side of the oil tank 11 are both provided with outlet terminals, which can facilitate the wiring and connection of the transformer. The high-voltage side outlet terminal is connected to the three-phase power supply on the high-voltage side, and the low-voltage side outlet terminal is connected to the load equipment on the low-voltage side, which simplifies the wiring process of the transformer and makes installation and maintenance more convenient.

[0027] Furthermore, the connection between the two sides of the low voltage is a delta-connected symmetrical phase-shifting structure, and the two line ends on the low voltage side are connected through the phase-modulating winding 2.

[0028] It should be noted that the connection between the two sides of the low voltage is a delta-connected symmetrical phase-shifting structure, which changes the phase difference between the two voltages through the phase-adjusting switch 9, balances the phase voltage and current on the low voltage side, thereby reducing the imbalance of the phase current and avoiding adverse effects on the transformer and the load due to the imbalance of the phase current.

[0029] Furthermore, the three-phase high-voltage winding 3 and the voltage regulating winding 4 are star-connected for load regulation, a voltage regulating switch 10 is connected in series between the high-voltage winding 3 and the voltage regulating winding 4, the three line ends of the high-voltage winding 3 are respectively connected to the three phases on the high-voltage side, and a high-voltage neutral point 8 is provided at the low-voltage side corner of the oil tank 11, and the high-voltage neutral point 8 is connected to the zero phase.

[0030] It should be noted that by connecting the three-phase high-voltage winding 3 and the voltage regulating winding 4 in a star shape, the high-voltage side voltage can be regulated. The star connection connects the neutral point of the high-voltage winding with the voltage regulating winding 4, so that the transformer can provide different voltage output options to adapt to the voltage requirements under different load conditions. The series connection of the voltage regulating switch 10 between the high-voltage winding 3 and the voltage regulating winding 4 plays a role in regulating the voltage. By opening or closing the voltage regulating switch 10, the series connection mode of the windings can be changed, thereby achieving adjustment of the output voltage. This flexibility enables the transformer to adapt to different load changes and provide a stable output voltage. By connecting the high-voltage neutral point 8 to the zero phase, a neutral point connection under symmetrical load and asymmetrical load can be provided, which can balance the voltage on the high-voltage side and provide insulation protection to the ground. At the same time, the setting of the high-voltage neutral point also helps to control voltage stability and fault protection.

[0031] Furthermore, the low voltage of the transformer is a double-split structure, and the connection group between the high and low voltages is Yd-d. The low voltage winding of the transformer is divided into two parts, each part is connected to the two line ends of the high voltage winding 3, forming a Yd connection. d indicates that there is a phase difference between the high voltage winding 3 and the low voltage winding. The high and low voltage transformation ratio and the amplitude of the voltage can be changed by the voltage regulating switch 10.

[0032] It should be noted that Y indicates that the high-voltage side is a star connection, and d indicates that the low-voltage side is a three-phase four-wire system, which is used to connect the star connection on the high-voltage side with the three-phase four-wire system on the low-voltage side. In the Yd-d connection group, the star connection on the high-voltage side is usually achieved by connecting the neutral point of the voltage regulating transformer to the ground, while the three-phase four-wire system on the low-voltage side usually consists of a three-phase power supply and a neutral wire, which is used to supply power to various load devices.

[0033] Furthermore, the excitation winding 1 is a single-branch end-outlet structure, which means that the excitation winding 1 has only one line outgoing from the end of the winding and connected to the excitation power supply or control system.

[0034] It should be noted that since the excitation winding 1 is a single branch, the current only needs to flow through one path, and the distribution and direction of the current are relatively simple and clear, easy to control and monitor, and the single-branch structure can reduce the length and volume of the excitation winding 1, making the overall structure of the equipment more compact and space-saving.

[0035] Furthermore, the phase-modulating winding 2 is a double U-shaped structure split axially up and down, which is used to control the phase difference of the current.

[0036] It should be noted that the upper and lower axial split structure can provide a more uniform magnetic field distribution, making the output voltage of the power equipment more stable and reliable, and the use of a double U-shaped structure can reduce the magnetic resistance of the magnetic circuit and improve the efficiency of the excitation winding 1 in generating a magnetic field.

[0037] Furthermore, the high-voltage winding 3 is a central lead-out structure, and the wires of the high-voltage winding 3 are led out from the center of the winding, so as to generate a magnetic field when the transformer is running.

[0038] It should be noted that the middle outgoing line structure can achieve balanced voltage distribution of the high-voltage winding 3, reduce the impact of voltage imbalance on equipment and systems, and the middle outgoing line structure can reduce the length and symmetry differences of the winding, reduce the possibility of damped oscillation, and improve the stability and working efficiency of the equipment.

[0039] Furthermore, the voltage regulating winding 4 is a parallel structure of upper and lower branches, which is used to provide a larger current capacity and lower voltage fluctuation.

[0040] It should be noted that the parallel structure of the upper and lower branches can achieve balanced distribution of current in the voltage regulating winding 4, reduce the impact of current imbalance on the equipment, and the parallel structure can increase the capacity of the voltage regulating winding 4, improve the power adjustment range of the equipment, and also increase the flexibility and adaptability of the winding to meet the voltage regulation requirements under different load conditions.

[0041] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A split phase-shifting transformer, characterized in that: include: An excitation winding (1), a phase-adjusting winding (2), a high-voltage winding (3), a voltage-regulating winding (4), an iron core (5), and an oil tank (11); the excitation winding (1), the phase-adjusting winding (2), the high-voltage winding (3), and the voltage-regulating winding (4) are sequentially sleeved and arranged on the iron core (5); and the excitation winding (1), the phase-adjusting winding (2), the high-voltage winding (3), the voltage-regulating winding (4), and the iron core (5) are all placed in the oil tank (11); The transformer has a three-phase structure, three excitation windings (1) are connected end to end to form a triangle connection, each excitation winding (1) is connected in series with two phase-adjusting windings (2), three vertices of the triangle connection are respectively connected to phase-adjusting windings (2) of different phases, the two phase-adjusting windings (2) are respectively connected to corresponding phase-adjusting switches (9), and three line ends of the phase-adjusting windings (2) are respectively connected to low-voltage three-phase; The high-voltage side of the oil tank (11) is provided with three high-voltage outlet terminals (6), and the high-voltage outlet terminals (6) are respectively connected to the three phases of the high voltage. The high-voltage side and the low-voltage side of the oil tank (11) are both provided with three low-voltage outlet terminals (7), and the low-voltage outlet terminals (7) on the high-voltage side are respectively connected to the three phases of the low voltage on the high-voltage side, and the low-voltage outlet terminals (7) on the low-voltage side are respectively connected to the three phases of the low voltage on the low-voltage side. The connection between the two sides of the low voltage is a delta-connected symmetrical phase-shifting structure, and the two line ends on the low-voltage side are connected via a phase-adjusting winding (2).

2. A split phase-shifting transformer according to claim 1, characterized in that: The three-phase high-voltage winding (3) and the voltage regulating winding (4) are connected in a star-shaped manner, a voltage regulating switch (10) is connected in series between the high-voltage winding (3) and the voltage regulating winding (4), three line ends of the high-voltage winding (3) are respectively connected to the three phases on the high-voltage side, a high-voltage neutral point (8) is provided at the low-voltage side corner of the oil tank (11), and the high-voltage neutral point (8) is connected to the zero phase.

3. A split phase-shifting transformer according to claim 1, characterized in that: The transformer low voltage has a double split structure, and the connection group between the high and low voltages is Yd-d. The transformer low voltage winding is divided into two parts, each part is connected to the two line ends of the high voltage winding (3), forming a Yd connection, d indicates that there is a phase difference between the high voltage winding (3) and the low voltage winding.

4. A split phase-shifting transformer according to claim 1, characterized in that: The excitation winding (1) is a single-branch end-out structure, which means that the excitation winding (1) has only one line outgoing from the end of the winding and connected to the excitation power supply or control system.

5. A split phase-shifting transformer according to claim 1, characterized in that: The phase-adjusting winding (2) is a double U-shaped structure split axially up and down, and is used to control the phase difference of the current.

6. A split phase-shifting transformer according to claim 1, characterized in that: The high-voltage winding (3) is a center-outlet structure, and the conductor of the high-voltage winding (3) is outlet from the center of the winding, and is used to generate a magnetic field when the transformer is running.

7. A split phase-shifting transformer according to claim 1, characterized in that: The voltage regulating winding (4) is a structure of upper and lower branches connected in parallel, and is used to provide a larger current capacity and a lower voltage fluctuation.

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