CN113451024B

CN113451024B - Stepless voltage regulating transformer

Info

Publication number: CN113451024B
Application number: CN202110707867.0A
Authority: CN
Inventors: 王晓兵; 周奇; 包正科
Original assignee: Jiangsu New Special Transformer Technology Corp ltd
Current assignee: Jiangsu New Special Transformer Technology Corp ltd
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2022-08-12
Anticipated expiration: 2041-06-24
Also published as: CN113451024A

Abstract

The invention relates to a stepless voltage regulating transformer, wherein an iron core comprises a main branch wound with a primary winding, a first branch wound with a secondary winding and a second branch for regulating voltage, wherein a stepless voltage regulating device is arranged in the second branch, and the magnetic flux passing through the first branch where the secondary winding is located is indirectly regulated by steplessly and continuously changing the magnetic flux area of the second branch, so that the output voltage of the secondary winding can be regulated steplessly, and particularly, the voltage can be regulated online in real time; meanwhile, magnetorheological liquid is filled around the adjusting part in the adjusting device, so that the problems of magnetic flux leakage and overlarge magnetic resistance caused by gaps can be reduced, the adjusting precision can be greatly improved, and the heat dissipation capacity of the gaps can be improved.

Description

Stepless voltage regulating transformer

Technical Field

The invention relates to the technical field of transformers, in particular to a rectifier transformer, and particularly relates to a transformer with a stepless voltage regulation function.

Background

The transformer is basic equipment for power transmission and distribution, and is widely applied to the fields of industry, agriculture, traffic and the like. The transformer is a device for changing alternating voltage by utilizing the far away of electromagnetic induction, main components are a primary coil, a secondary coil and an iron core, and the main functions of the transformer are as follows: voltage transformation, current transformation, impedance transformation, isolation, voltage stabilization, and the like.

The transformer consists of a closed core providing a flux path and two coil windings wound around the core, wherein the winding connected to the power source is the primary winding with N1 turns, and the other winding is connected to the load, the secondary winding with N2 turns. The primary winding is also called the primary winding, and the secondary winding is also called the secondary winding. When a sinusoidal alternating voltage U1 is applied across the primary winding, there is an alternating current I1 in the wire and an alternating magnetic flux φ 1 is generated, which passes through the primary winding and the secondary winding along the core to form a closed magnetic circuit, inducing a mutual inductance potential U2 in the secondary winding, and φ 1 also induces a self-inductance potential E1 on the primary winding, E1 in a direction opposite to the direction of the applied voltage U1 and in a similar magnitude, thereby limiting the magnitude of I1. In order to maintain the existence of the magnetic flux φ 1, a certain electric energy consumption is required, and the transformer itself has a certain loss, although the secondary is not connected with a load, a certain current still exists in the primary winding, and the current is called as 'no-load current'. If the secondary is connected with a load, the secondary winding generates current I2 and thus generates magnetic flux phi 2, the direction of phi 2 is opposite to phi 1, and the mutual cancellation effect is achieved, so that the total magnetic flux in the iron core is reduced, and the primary self-inductance voltage E1 is reduced, and as a result, I1 is increased, and the primary current is in close relation with the secondary load. When the secondary load current increases, I1 increases, phi 1 also increases, and the increasing part of phi 1 exactly supplements the part of the magnetic flux which is offset by phi 2 to keep the total magnetic flux in the iron core constant.

In various electrical devices, a transformer is used in a large amount to convert the voltage of a primary power supply into the voltage of a secondary power supply required by a subsequent device or circuit, and the voltage values of the primary voltages in the various electrical devices are various, such as 24V, 48V, 110V, 220V, 3000V, etc., while the voltage values of the secondary voltages are more complicated, so that in the design process of the electrical devices, a specific transformer needs to be selected according to the condition of a specific primary power supply and the condition of a secondary power supply of a specific electrical device, which makes the conditions of the input voltage and the output voltage of the transformer very complicated, and the specification of the transformer cannot be standardized. Although the existing transformer is provided with voltage regulating contacts, the voltage regulating contacts are several contacts led out from different positions of the secondary coil, and the voltages led out by the voltage regulating contacts are several discrete points, so that the specific voltage regulating requirements can be met, and the wide universality cannot be realized.

Therefore, it is an urgent need in the art to provide a transformer with stepless voltage regulation function, so that the transformer has a continuously adjustable transformation ratio and outputs a continuously variable voltage to meet the requirements of different transformation, thereby providing wide versatility and applicability.

Disclosure of Invention

In order to solve the technical problem, the invention provides a stepless voltage regulating transformer, which comprises an iron core, a primary winding and a secondary winding, wherein the iron core comprises a main branch, a first branch and a second branch, a first end of the first branch and a first end of the second branch are connected to a first end of the main branch, a second end of the first branch and a second end of the second branch are connected to a second end of the main branch, the primary winding is wound on the main branch of the iron core, the secondary winding is wound on the first branch of the iron core, the second branch of the iron core is provided with a gap, the stepless voltage regulating transformer further comprises a voltage regulating device, the voltage regulating device is arranged in the gap, and at least one part of the voltage regulating device can move in the gap in a sliding manner.

Further, the pressure regulating device includes first magnetic conduction board and second magnetic conduction board, first magnetic conduction board, second magnetic conduction board set up respectively the both sides in clearance, and respectively with seamless ground fixed connection of second branch road, the pressure regulating device is still including hindering the magnetic plate, hinder the magnetic plate setting between first magnetic conduction board and second magnetic conduction board, and hinder the magnetic plate and enclose into a slip space with first magnetic conduction board, second magnetic conduction board, the at least part in slip space is located in the clearance.

Further, the pressure regulating device further comprises a sliding part, the sliding part comprises a piston and a piston rod, the piston and the piston rod are located in the sliding space, the piston rod is connected with the piston and can drive the piston to move in the sliding space in a sliding mode, and the piston at least covers the cross section of the second branch.

Further, the piston is composed of a first portion made of a ferromagnetic material and a second portion made of a diamagnetic material.

Further, the first portion is made of at least one of iron, nickel, cobalt, and the second portion is made of graphite or copper.

Further, the first portion and the second portion are arranged back and forth in the sliding direction of the piston, or the first portion and the second portion are arranged left and right with respect to the sliding direction of the piston.

Further, the pressure regulating device further comprises an actuator, wherein the actuator is connected with the piston rod and drives the piston to move in the sliding space in a sliding mode through the piston rod.

Furthermore, a magnetorheological fluid is arranged in the sliding space, and the magnetorheological fluid consists of magnetic particles, a base fluid and an additive.

Further, when the piston slides to overlap with the cross section of the second branch, the distance between the piston and the first magnetic conductive plate and the second magnetic conductive plate is less than 2mm, preferably less than 1 mm.

The voltage regulating device further comprises a controller and a secondary winding output voltage sensor, wherein the controller is connected with the actuator and the secondary winding output voltage sensor, can acquire data from the secondary winding output voltage sensor and sends instructions to the actuator.

The implementation of the invention has the following beneficial effects: according to the stepless voltage regulating transformer, the second branch circuit for stepless voltage regulation is arranged in the iron core, and the magnetic flux area of the second branch circuit is steplessly and continuously changed, so that the magnetic flux passing through the first branch circuit where the secondary winding is located is indirectly regulated, the output voltage of the secondary winding can be steplessly regulated, and particularly, online real-time voltage regulation can be carried out; meanwhile, magnetorheological liquid is filled around the adjusting part in the adjusting device, so that the problems of magnetic flux leakage and overlarge magnetic resistance caused by gaps can be reduced, the adjusting precision can be greatly improved, and the heat dissipation capacity of the gaps can be improved.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural view of a stepless voltage regulating transformer of the present invention.

Fig. 2 is a schematic view of the piston structure of the present invention.

Reference numerals: 1. a main branch; 2. a first branch; 3. a second branch circuit; 4. a primary winding; 5. a secondary winding; 6. a gap; 7. a first magnetic conductive plate; 8. a second magnetic conductive plate; 9. a magnetic resistance plate; 10. a piston; 11. a piston rod; 12. an actuator; 13. a secondary winding output voltage sensor; 14. a second portion; 15. a first portion.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without any inventive step, are within the scope of the present invention.

In order to solve the above problems, the present invention provides a stepless voltage regulating transformer, as shown in fig. 1, the stepless voltage regulating transformer includes an iron core, a primary winding 4 and a secondary winding 5, which are particularly low, the iron core is in a shape of a Chinese character ri, and the iron core includes three longitudinal branches, namely, a main branch 1, a first branch 2 and a second branch 3. The main branch 1 is located in the middle of the iron core, and the first branch 2 and the second branch 3 are located on two sides of the main branch 1. The first end of the first branch and the first end of the second branch are connected to the first end of the main branch, and the second end of the first branch and the second end of the second branch are connected to the second end of the main branch, so that the iron core in the shape of the Chinese character 'ri' is formed.

A primary winding 4 is wound on the main branch 1 and a secondary winding 5 is wound on the first branch 2. An input power supply is connected to the primary winding 4, the alternating input power supply being able to form an alternating magnetic field in the main branch 1 and a closed magnetic field via the first branch and the second branch by means of a magnetic flux flow path built up by the core. Preferably, the cross-sectional area of the main branch 1 is greater than the cross-sectional area of the first branch 2 and greater than the cross-sectional area of the second branch 3. The magnetic flux of the first branch 2 and the second branch 3 is approximately determined by the cross-sectional area of the first branch 2 and the second branch 3, or at least is the main influence factor.

When the alternating magnetic field flows through the first branch 2, the alternating magnetic field generates an induced electromotive force in the secondary winding 5, so that the secondary winding 5 outputs a voltage. By changing the number of turns of the primary winding 4 and the secondary winding 5, the transformation ratio of the input voltage to the output voltage can be adjusted. However, such an adjustment method is generally applicable only to the transformer assembly and design process, and once the transformer assembly is completed, it is difficult to change the transformation ratio by changing the number of winding turns of the primary winding 4 and the secondary winding 5.

In order to be able to steplessly adjust the magnetic flux flowing through the first branch 2, as shown in fig. 1, a gap 6 is provided in the second branch 3 of the core, i.e. the second branch 3 is discontinuous, being divided into two parts, between which the gap 6 is arranged. The width of the gap 6, i.e. the distance between the two parts, is typically set to be greater than 5cm, depending on the size of the transformer and the voltage. The gap at such a distance allows a large magnetic resistance between two opposite parts of the second branch 3, and the magnetic field is greatly hindered at the position of the gap, so that most of the magnetic flux flows through the first branch 2.

In order to be able to regulate the magnetic flux flowing through the second branch 3, a voltage regulating device is arranged in the gap 6 of the second branch 3, as shown in fig. 1. The pressure regulating device comprises a first magnetic conduction plate 7 and a second magnetic conduction plate 8, wherein the first magnetic conduction plate 7 and the second magnetic conduction plate 8 are respectively arranged on two sides of the gap 6 and respectively connected with two parts of the second branch 3 in a gapless mode, and particularly, a welding or fixing part connecting mode can be adopted. The first magnetic conductive plate 7 and the second magnetic conductive plate 8 are made of magnetic conductive materials, so that the magnetic field flowing through the second branch 3 can pass through the first magnetic conductive plate 7 and the second magnetic conductive plate 8, thereby forming a magnetic flux flow path. Further, the pressure regulating device further includes a magnetic resistance plate 9, the magnetic resistance plate 9 is made of diamagnetic materials, the magnetic resistance plate 9 is 4 pieces, and is arranged between the first magnetic conduction plate 7 and the second magnetic conduction plate 8, and the magnetic resistance plate 9, the first magnetic conduction plate 7 and the second magnetic conduction plate 8 enclose a sliding space, as shown in fig. 1, the sliding space is of a cubic structure. At least part of the sliding space is located in the gap 6, preferably the cross-sectional area of the sliding space is larger than the cross-sectional area of the gap 6 and can completely cover the cross-sectional area of the gap 6.

In the sliding space, a slider is provided. As shown in fig. 1, the slider comprises a piston 10 and a piston rod 11, the piston rod 11 is connected with the piston 10, and an actuator 12 is connected to the piston rod 11 and is capable of driving the piston rod 11 to move longitudinally, thereby driving the piston 10 to slide longitudinally in a sliding space. The piston 10 is completely accommodated in said sliding space, the cross-sectional area of the piston 10 being larger than the cross-sectional area of said second branch 3, so that the piston 10 is able to completely cover the cross-section of the second branch 3 when the piston 10 is slid to a certain position.

Preferably, when the piston 10 is completely slid out, i.e. in the leftmost position as shown in fig. 1, the cross section of the piston 10 does not overlap with the cross section of the second branch 3; when the piston 10 is slid into a certain position, the projection of the cross section of the second branch 3 onto the piston 10 is completely received by the piston 10.

As for the distance between the piston 10 and the first magnetic conductive plate 7 and the second magnetic conductive plate 8, the smaller the distance, the better; however, in order to ensure that the piston 10 can slide smoothly in the sliding space, the distance between the piston 10 and the first and second magnetic conductive plates 7 and 8 is set to be less than 2mm, preferably less than 1 mm.

At least part of said piston 10 is made of magnetically permeable material, preferably ferromagnetic material, whereby the piston 10 is able to constitute a magnetic flux path with said second branch 3 when the piston 10 is slid into overlapping relation with said second branch 3; the larger the area of overlap, the larger the area of the flux path. By adjusting the overlapping area of the piston 10 and the second branch 3, the magnetic flux area of the second branch 3 can be adjusted, and the change of the magnetic flux area of the second branch 3 further affects the magnetic flux flowing through the first branch 2, thereby changing the output voltage of the secondary winding.

In order to be able to regulate the output voltage of the secondary winding more precisely and precisely, as shown in fig. 2, the piston 10 is composed of a first part 15 and a second part 14, the first part 15 being made of a ferromagnetic material and the second part 14 being made of a diamagnetic material. By such an arrangement, the adjustment of the magnetic conductive area of the piston 10 during the adjustment process is more accurate, and thus the adjustment of the magnetic conductive area of the second branch 3 is also more accurate. As shown in fig. 2, the first portion 15 and the second portion 14 are arranged in a front-rear direction in the sliding direction of the piston 10, the first portion 15 and the second portion 14 may be arranged in a front-rear direction and each have only one, and the first portion 15 and the second portion 14 may be arranged in a plurality of front-rear direction and spaced apart from each other. Alternatively, the first portion 15 and the second portion 14 may be arranged in the left-right direction with respect to the sliding direction of the piston 10, the first portion 15 and the second portion 14 may each have only one and be arranged in the left-right direction, and the first portion 15 and the second portion 14 may have a plurality and be arranged in the left-right direction at intervals.

Further, the first portion 15 is made of at least one of iron, nickel, and cobalt, and the second portion 14 is made of graphite or copper.

Further, in order to automatically and intelligently adjust the piston 10, a controller and a secondary winding output voltage sensor 13 are provided, wherein the controller is connected with the actuator 12 and the secondary winding output voltage sensor 13, can acquire data from the secondary winding output voltage sensor 13 and send instructions to the actuator 12 to adjust the position of the piston 10. The controller adopts a PID control mode, can receive a desired output voltage value input by an operator, controls the actuator 12 to adjust the position of the piston 10, obtains a real-time value of the secondary winding output voltage sensor 13, takes the secondary winding output voltage output in real time as feedback, and takes the difference value between the two values as an adjustment quantity compared with the desired output voltage value input by the operator, and further controls the actuator 12 to adjust the position of the piston 10, so as to finally obtain the desired secondary winding output voltage value. In this way, an automatic and intelligent control and regulation can be established, and also a remote stepless regulation of the voltage can be achieved, or the desired value of the secondary winding output voltage can be transmitted to the controller locally by means of an input device such as a push button.

Further, the controller is also provided with an alarm module, and the alarm module is connected with the piston displacement limit sensor and can sense the maximum and minimum moving positions of the piston 10. When the piston 10 moves to the maximum or minimum position and still cannot meet the input expected secondary winding output voltage, the alarm module sends out warning information to remind an operator that the input expected voltage value cannot be met.

In order to further reduce the problems of magnetic resistance and magnetic flux leakage of the air gap of the gap 6 and to improve the adjustment accuracy, the invention proposes that a magnetorheological fluid consisting of magnetic particles, a base fluid and an additive is arranged in the sliding space. The piston 10 is wrapped by the magnetorheological fluid in the sliding space, so that the magnetorheological fluid can be filled in the gap between the piston 10 and the first magnetic conduction plate 7 and the second magnetic conduction plate 8, the gap between the piston 10 and the first magnetic conduction plate 7 and the second magnetic conduction plate 8 has better magnetic conduction capability and performance, and the magnetic resistance in the region is smaller. Under normal conditions, the heating condition at the position of the gap 6 is relatively serious, the existing transformer usually needs to face the heat dissipation problem of the heating, and due to the existence of the magnetorheological liquid, the transformer can play a good cooling effect on the heat dissipation, and can dissipate the heat through other positions of the first magnetic conduction plate 7, the second magnetic conduction plate 8 and the magnetic resistance plate 9, so that the heat dissipation capability of the gap 6 can be greatly improved.

For the performance of the magnetorheological fluid, the size and concentration of the magnetic particles can be set to be smaller and lower, so that the magnetorheological fluid only changes to be higher in viscosity and cannot be solidified under the action of the magnetic field flowing through the second branch 3, and the resistance of the piston 10 moving in the sliding space cannot be too large.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A stepless voltage regulating transformer comprises an iron core, a primary winding and a secondary winding, wherein the iron core comprises a main branch, a first branch and a second branch, the first end of the first branch and the first end of the second branch are connected to the first end of the main branch, the second end of the first branch and the second end of the second branch are connected to the second end of the main branch, the primary winding is wound on the main branch of the iron core, the secondary winding is wound on the first branch of the iron core, the second branch of the iron core is provided with a gap, the stepless voltage regulating transformer further comprises a voltage regulating device, the voltage regulating device is arranged in the gap, and at least one part of the voltage regulating device can slidably move in the gap;

the pressure regulating device comprises a first magnetic conduction plate and a second magnetic conduction plate, the first magnetic conduction plate and the second magnetic conduction plate are respectively arranged on two sides of the gap and are respectively fixedly connected with the second branch in a gapless manner, the pressure regulating device further comprises a magnetic resistance plate, the magnetic resistance plate is arranged between the first magnetic conduction plate and the second magnetic conduction plate, the magnetic resistance plate, the first magnetic conduction plate and the second magnetic conduction plate enclose a sliding space, and at least part of the sliding space is positioned in the gap;

the pressure regulating device further comprises a sliding piece, the sliding piece comprises a piston and a piston rod, the piston and the piston rod are located in the sliding space, the piston rod is connected with the piston and can drive the piston to move in the sliding space in a sliding mode, and the piston at least covers the cross section of the second branch;

the magnetorheological fluid is arranged in the sliding space and consists of magnetic particles, base fluid and additives, and the magnetorheological fluid is used for filling a gap between the piston and the first magnetic conduction plate and a gap between the piston and the second magnetic conduction plate.

2. The step-less voltage regulating transformer of claim 1, wherein the piston is comprised of a first portion and a second portion, the first portion being made of a ferromagnetic material and the second portion being made of a diamagnetic material.

3. The step-less voltage regulating transformer of claim 2, wherein the first portion is made of at least one of iron, nickel, and cobalt, and the second portion is made of graphite or copper.

4. The stepless voltage regulating transformer according to claim 2, wherein the first part and the second part are arranged back and forth in the sliding direction of the piston, or the first part and the second part are arranged left and right with respect to the sliding direction of the piston.

5. The step-less voltage regulating transformer according to any one of claims 1 to 4, wherein the voltage regulating device further comprises an actuator connected to the piston rod and driving the piston to move slidingly in the sliding space through the piston rod.

6. The step-less voltage regulating transformer of claim 1, wherein when the piston slides to overlap the cross section of the second branch, the spacing between the piston and the first and second magnetically permeable plates is less than 2 mm.

7. The stepless voltage regulating transformer of claim 5, wherein the voltage regulating device further comprises a controller and a secondary winding output voltage sensor, wherein the controller is connected with the actuator and the secondary winding output voltage sensor and can acquire data from the secondary winding output voltage sensor and send instructions to the actuator.