TWI442420B - Can increase the leakage of the transformer structure - Google Patents

Description

Transformer structure that can increase leakage inductance

The invention relates to a transformer structure, in particular to a transformer structure which can increase leakage inductance.

The so-called leakage inductance, or Leakage inductance, means that when the coupling coefficient between the primary winding and the secondary winding in the transformer is less than 1, the partial winding of the transformer will not function as a transformer, and only a similar suppression will occur. The effect of the inductor, the inductor that does not have a transformer effect in this part, is called the leakage inductance.

In general, the leakage inductance of the transformer will cause the output voltage of the transformer to decrease, and the power cannot be completely converted, resulting in the loss of energy. Therefore, the early transformers are mostly unpleasant for the leakage inductance. However, the voltage drop characteristic of the current passing through can be used to make the transformer generate a large leakage inductance, and can be applied to a fluorescent lamp having a negative impedance characteristic, a neon lamp, and other current stabilizers of the discharge lamp, and a curved shape. Connected ballast, microwave oven vacuum tube stabilizer, etc.

In addition, the secondary winding is connected in parallel with the resonant capacitor, and the resonant inductance (LC resonance) is generated as a resonant transformer by the leakage inductance of the secondary side, and the resonant transformer can be applied to a fluorescent lamp electronic ballast, neon electronic Ballast, cold cathode tube inverter or Tesla coil.

On the other hand, in the power supply system of a new generation of electronic products, the transformer is mainly a transformer with a leakage inductance type. The current input to the power supply system first passes through the LC resonant circuit formed by the leakage inductance L inherent to the primary winding of the transformer and a capacitive element C. At the same time, a current that approximates a half sine wave will pass through the power field effect transistor switch. When the current is At zero, the switch will turn on, and after half a sine wave, the current will return to zero and the switch will turn off. The soft switch design with resonant circuit can reduce the loss of the switch and reduce the noise.

Therefore, how to increase the leakage inductance of the transformer has been the goal of various companies to actively develop.

In view of the above reasons, the Patent No. I291183 of the Republic of China discloses a transformer structure comprising a main stage winding, a primary winding, a winding frame module and a core group. The core assembly is disposed in the bobbin module, and the bobbin module includes a first winding component and a second winding component, wherein the first winding component is used for winding the main winding. The second winding component is for winding the secondary winding. Wherein, the first winding member and the second winding member have a first side plate, so that the main winding is separated from the secondary winding to increase leakage inductance and electrical safety distance. However, the technique of increasing the leakage inductance by adjusting the distance is bound to increase the volume of the overall transformer, which is contrary to the miniaturization of electronic devices.

In order to solve the above problem, the Patent No. I304674 of the Republic of China discloses a transformer and a lamp tube structure using the same, comprising a bobbin, a primary winding group, a secondary winding group, and a first magnetic Core, a second core. The bobbin has a through hole. The primary side winding group and the secondary side winding group are respectively wound on the winding frame. The first core is embedded in the through hole. The second core has a first end and a second end, respectively coupled to the first core. The second magnetic core further has a first protruding portion disposed between the first end and the second end, and the first protruding portion is disposed between the primary side winding group and the secondary side winding group, by the first The protrusion guides the magnetic field line to one side. However, the above structure is disposed on the side between the primary side winding group and the secondary side winding group, the guiding magnetic force is limited, the added leakage inductance value is also limited, and the structure thereof cannot adjust the appropriate leakage inductance value. At the application level, it is still insufficient.

Accordingly, the Republic of China No. M300858 discloses a transformer with adjustable leakage inductance, comprising a first core, a bobbin and a second core. The first core is placed in the bobbin. The second core includes a magnetic conductive component and a leakage sensing component The magnetic component covers one side of the bobbin and forms a closed magnetic circuit with the first core. The leakage sensing component is disposed on the magnetic guiding component and is movable relative to the magnetic guiding component to change the distance between the leakage sensing component and the bobbin for adjusting the leakage inductance of the leakage sensing component to the bobbin. However, the leakage sensing element described above is still disposed on one side of the bobbin. As in the patent No. I304674, the added leakage inductance is limited due to structural limitations, and the effect of effectively increasing the leakage inductance cannot be achieved.

In view of the above reasons, the patent of the Republic of China No. M336515 discloses a transformer. The transformer includes at least one high voltage coil, at least one low voltage coil, and at least one soft magnetic colloid. The soft magnetic gel system is disposed between the high voltage coil and the low voltage coil to increase the leakage inductance value. However, the above soft magnetic colloids must be molded once in the process. If different leakage inductance values are required, it is necessary to open different molds for design. Therefore, it is inconvenient and economical in the production process.

The main object of the present invention is to provide a transformer structure with high leakage inductance, relatively small volume, and adjustable leakage inductance value according to requirements, thereby improving the practicability of the leakage inductance transformer.

To achieve the above object, the present invention provides a transformer structure capable of increasing leakage inductance, comprising a bobbin, a horizontal core group, and at least one vertical core. The bobbin includes a first winding portion, a second winding portion disposed coaxially with the first winding portion, and an interval disposed between the first winding portion and the second winding portion Section. The horizontal magnetic core group is disposed in the first winding portion and the second winding portion, and forms a first magnetic force passing through the spacing portion between the first winding portion and the second winding portion path. The vertical magnetic core is disposed in the spacing section perpendicular to an axial direction of the first winding portion and the second winding portion. The vertical magnetic core guides the magnetic lines of force on the first magnetic path to the one end of the horizontal magnetic core group and forms a second magnetic path, by guiding the magnetic lines of the first magnetic path to the first magnetic path The second magnetic path enhances the leakage inductance value.

Further, the spacer segment includes at least one magnetic core setting region disposed on the side of the first magnetic path and axially corresponding to the first winding portion and corresponding to each vertical magnetic core. .

Further, the transformer structure includes a plurality of vertical magnetic cores each having an arc-shaped structure, and being disposed adjacent to each other, the spacing portion is disposed between the first winding portion and the second winding portion.

Further, the perpendicular magnetic cores respectively comprise a connecting portion, and the connecting portions different from the perpendicular magnetic core are joined to each other such that the two perpendicular magnetic cores form a ring-shaped structure.

Further, the spacer segment includes at least one magnetic penetration region lacking the vertical magnetic core disposed on one side of the magnetic path.

Further, the spacer region corresponds to each of the vertical magnetic cores including at least one encapsulation portion enclosing the vertical magnetic core in the spacing region.

Further, the transformer structure capable of increasing leakage inductance further includes another vertical magnetic core disposed in the interval section perpendicular to an axial direction of the first winding portion and the second winding portion, and a setting An insulating portion between the two perpendicular magnetic cores.

Further, the transformer structure capable of increasing leakage inductance further includes a magnetic conductive frame extending from the horizontal magnetic core group and surrounding the first winding portion and the circumferential side of the second winding portion.

Further, the horizontal magnetic core group and the material of the magnetic conductive frame are ferrous salts.

The material of the magnetic conductive frame is selected from the group consisting of a silicon steel sheet, an iron sheet, and an iron powder core.

Further, the material of the horizontal core group is selected from the group consisting of a silicon steel sheet, an iron sheet, and an iron powder core.

Further, the material of the perpendicular magnetic core is a ferrous salt.

Therefore, in the present invention, the magnetic path is guided outward from the side periphery of the spacer section to the first winding portion by a vertical core disposed in the spacer section and vertically disposed on the horizontal core group. This increases the leakage inductance of the transformer. On the other hand, the perpendicular magnetic core of the present invention may be a material of a ferrous salt, thereby reducing the high thermal reaction caused by the eddy current loss.

10‧‧‧ Winding frame

11‧‧‧First winding department

111‧‧‧First Fixed Department

12‧‧‧Second winding department

121‧‧‧Second fixed department

20‧‧‧Vertical core

21, 21c‧‧‧ Connection Department

20a, 20b, 20c‧‧‧ vertical core

30‧‧‧Horizontal core group

40‧‧‧Magnetic framework

50‧‧‧Insulation

R‧‧‧ interval section

R1‧‧‧Magnetic core setting area

R2‧‧‧Packing Department

R3‧‧‧Magnetic penetration zone

L1‧‧‧First magnetic path

L2‧‧‧Second magnetic path

Figure 1 is a schematic exploded view of the first embodiment of the present invention.

Figure 2 is a cross-sectional view showing the structure of the first embodiment of the present invention.

Fig. 3 is a schematic view showing the magnetic path of the first embodiment of the present invention.

Figure 4 is a schematic cross-sectional view showing a second embodiment of the present invention.

Figure 5 is a schematic cross-sectional view showing a third embodiment of the present invention.

Figure 6 is a cross-sectional view showing a fourth embodiment of the present invention.

The detailed description and technical contents of the present invention will now be described with reference to the following drawings: Referring to FIG. 1 and FIG. 2, FIG. 1 is a structural exploded view and a schematic cross-sectional view of the structure, as shown in the figure: A transformer structure capable of increasing leakage inductance, comprising a bobbin 10, a horizontal core group 30 passing through the bobbin 10, and two disposed on the bobbin 10 and vertically disposed on the horizontal core group 30 vertical core 20. The bobbin 10 has a first winding portion 11 formed with a first magnetic path L1 (as shown in FIG. 3), and a pair of the first winding portion 11 is disposed in front of the first winding portion 11 for the first magnetic path A second winding portion 12 through which L1 passes, and a spacing portion R provided between the first winding portion 11 and the second winding portion 12 for the first magnetic path L1 to pass. The spacing section R includes a core setting area R1 disposed on the first magnetic path L1. The two perpendicular magnetic cores 20 are assembled to the magnetic core setting region R1 in a manner of being clamped up and down, and guide magnetic lines of force on the first magnetic path L1 to the horizontal magnetic core group 30 near the first winding portion 11 One end, the two perpendicular magnetic cores 20 have an arc-shaped structure, respectively The spacing section R is disposed to surround the first winding portion 11 and the second winding portion 12 . In the process, the present invention can adjust the required leakage inductance value by increasing or decreasing the number of the vertical cores 20.

The two perpendicular magnetic cores 20 are coupled to each other for fixing to the bobbin 10. The vertical magnetic cores 20 respectively include a connecting portion 21, and the connecting portions 21 of the perpendicular magnetic core 20 can be mutually coupled to each other. The vertical magnetic core 20 is formed into a ring-shaped structure, and the two vertical magnetic cores 20 are respectively placed on the first and second fixing portions 111 and 121 of the first and second winding portions 11 and 12 respectively. (as shown in Figure 3). The connecting portions 21 are combined with each other in a gluing manner, or in a combination of any application mechanical concepts such as fastening, fitting, and the like, which are not limited in this embodiment, and will be described first. The material of the vertical core 20 can be a silicon steel sheet, an iron sheet, and an iron powder core or other metal having a high magnetic permeability. In the present embodiment, the perpendicular magnetic core 20 is made of an iron powder core doped with a ferrous salt (ferrate) material, thereby reducing the high thermal effect caused by the eddy current loss.

In order to increase the magnetic permeability of the transformer of the present invention, the present invention employs a double E-shaped metal sheet to combine the bobbin 10 including the horizontal magnetic flux passing through the first winding portion 11 and the second winding portion 12. The core group 30 and a magnetic conductive frame 40 extending from the horizontal core group 30 and surrounding the first winding portion 11 and the second winding portion 12 on the circumferential side. The material of the horizontal magnetic core group 30 and the magnetic conductive frame 40 may be a silicon steel sheet or an iron piece, or may be the same iron mixed with ferrous salt as the first and second annular magnetic conductive sheets 21 and 22. The powder core, thereby avoiding the high thermal effect caused by the eddy current loss.

Referring to FIG. 3, it is a schematic diagram of a magnetic path according to a first embodiment of the present invention. As shown in the figure, after the first winding portion 11 receives an AC voltage source, a plurality of first magnetic paths are formed. L1, and by the horizontal core group 30 passing through the first winding portion 11 and the second winding portion 12, electromagnetic coupling induction is generated, thereby generating an induced current. The two perpendicular cores 20 are disposed on the circumferential side of the first magnetic path L1, and the two perpendicular cores 20 respectively apply magnetic lines of force in the first magnetic path L1 on the horizontal core group 30 to the horizontal magnetic field. Core group The direction of one end of the first winding portion 11 is guided to form a second magnetic path L2, so that part of the magnetic lines of force do not pass through the second winding portion 12, thereby generating leakage flux, and further increasing The leakage inductance allows the transformer structure of the present invention to increase the leakage inductance value without increasing the distance between the first winding portion 11 and the second winding portion 12, thereby providing a small size and a high leakage inductance.

Referring to FIG. 4, it is a schematic cross-sectional view of a second embodiment of the present invention. As shown in the figure, the transformer of the present embodiment is different from the transformer of the first embodiment in the design of the vertical magnetic core, and the rest are the same. The part will not be described again.

In the embodiment, the vertical core 20a includes two perpendicular cores 20a respectively disposed on the first fixing portion 111 and the second fixing portion 121. The vertical magnetic core 20a can be divided into two upper and lower pieces, and the first fixing portion 111 and the second fixing portion 121 are respectively sandwiched from upper and lower sides, thereby fixing the two perpendicular magnetic cores 20a to the first First, the second fixing portions 111, 121. An insulating portion 50 is interposed between the two perpendicular magnetic cores 20a, and the required leakage inductance value is adjusted by replacing the insulating portion 50 having a different thickness.

Please refer to FIG. 5, which is a cross-sectional view of a third embodiment of the present invention. As shown in the figure, the transformer of the embodiment differs from the transformer of the first embodiment in the design of the vertical core, and the rest are the same. The part will not be described again.

In this embodiment, the outer diameter of the two perpendicular magnetic cores 20b is slightly smaller than the outer diameters of the partitions of the first and second winding portions 11, 12 on both sides, thereby forming an embedding for plastic injection molding. a region, wherein the plastic is surrounded by the first and second winding portions 11 and 12 and the circumferential side of the vertical core 20b by injection molding to form a package portion R2 enclosing the vertical core 20b. Thereby, the vertical core 20b is fixed.

Please refer to FIG. 6 for a cross-sectional view of a fourth embodiment of the present invention. As shown in the figure, the transformer of the embodiment differs from the transformer of the first embodiment in the design of the vertical core, and the rest are the same. The part will not be described again.

In this embodiment, the three vertical cores 20c are included, and the vertical cores 20c each include a connecting portion 21c and are combined with each other to form an annular structure, and the interval portion R is first. The magnetic path L1 side includes at least one magnetic penetration region R3 lacking the vertical magnetic core 20c, thereby adjusting the magnetic lines of force passing through the second winding group 12. Therefore, in this embodiment, the number of the vertical cores 20c can be adjusted in accordance with the requirements of the process, thereby controlling the required leakage inductance value.

In summary, the present invention guides the magnetic path outward from the side periphery of the spacing section back to the first winding by a vertical core disposed in the spacing section and vertically disposed on the horizontal core group. To increase the leakage inductance of the transformer. In addition, the present invention can adjust the required leakage inductance value by adjusting the number of vertical cores to create a magnetic penetration region for the magnetic flux to penetrate between the vertical cores or by adjusting the thickness of the vertical core. On the other hand, the perpendicular magnetic core of the present invention may be a material of a ferrous salt, thereby reducing the high thermal reaction caused by the eddy current loss.

The present invention has been described in detail above, but the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Variations and modifications are still within the scope of the patents of the present invention.

10‧‧‧ Winding frame

11‧‧‧First winding department

12‧‧‧Second winding department

20‧‧‧Vertical core

21‧‧‧Connecting Department

30‧‧‧Horizontal core group

40‧‧‧Magnetic framework

R‧‧‧ interval section

Claims (12)

A transformer structure capable of increasing leakage inductance, comprising: a bobbin comprising a first winding portion, a second winding portion disposed coaxially with the first winding portion, and a first winding disposed on the first winding a spacing section between the line portion and the second winding portion; a horizontal core group penetrating in the first winding portion and the second winding portion and in the first winding portion and the first Forming a first magnetic path passing through the spacing section between the two winding portions; and at least one perpendicular magnetic core, the vertical spacing of the first winding portion and the second winding portion is annularly disposed in the spacing region And surrounding the winding frame, the vertical magnetic core guiding the magnetic lines of force on the first magnetic path to the horizontal core group adjacent to one end of the first winding portion and forming a second magnetic path A magnetic field line of a magnetic path leads to the second magnetic path to increase the leakage inductance value. The transformer structure of claim 1, wherein the spacer section includes at least one axis surrounding the first winding portion and the second winding portion on a side of the first magnetic path. A magnetic core setting area is provided to and corresponding to each vertical core. The transformer structure according to claim 2, wherein the transformer structure comprises a plurality of vertical magnetic cores, wherein the vertical magnetic cores are respectively arranged in an arc shape, and are arranged adjacent to each other to surround the interval portion. Between the first winding portion and the second winding portion. The transformer structure for increasing leakage inductance according to claim 3, wherein the vertical magnetic cores respectively comprise a connecting portion, and the connecting portions of the perpendicular magnetic cores are joined to each other to form a ring-shaped structure. . The transformer structure of claim 3, wherein the spacer segment comprises at least one magnetic penetration region lacking the vertical core disposed on a side of the first magnetic path. A transformer structure capable of increasing leakage inductance according to claim 1, wherein the spacer region corresponds to each of the vertical cores including at least one encapsulation portion enclosing the vertical core in the spacer region. The transformer structure capable of increasing leakage inductance according to claim 1, further comprising another one in which the first winding portion and the second winding portion are perpendicularly disposed in the spacing portion. a vertical core, and an insulating portion disposed between the two perpendicular cores. The transformer structure for increasing leakage inductance according to claim 1, further comprising a magnetic conductive frame extending from the horizontal magnetic core group and surrounding the first winding portion and the second winding portion . The transformer structure capable of increasing leakage inductance according to claim 8, wherein the horizontal core group and the material of the magnetic conductive frame are ferrous salts. The transformer structure for increasing leakage inductance according to claim 8 is characterized in that the material of the magnetic conductive frame is selected from the group consisting of a silicon steel sheet, an iron sheet, and an iron powder core. The transformer structure capable of increasing leakage inductance according to claim 1, wherein the material of the horizontal core group is selected from the group consisting of a silicon steel sheet, an iron sheet, and an iron powder core. The transformer structure capable of increasing leakage inductance according to claim 1, wherein the material of the vertical core is a ferrous salt.