CN201765917U

CN201765917U - High-power switching transformer

Info

Publication number: CN201765917U
Application number: CN2010202515828U
Authority: CN
Inventors: 张庆祥; 赵岩岩
Original assignee: QINGDAO AINUO INSTRUMENT CO Ltd
Current assignee: QINGDAO AINUO INSTRUMENT CO Ltd
Priority date: 2010-06-28
Filing date: 2010-06-28
Publication date: 2011-03-16
Anticipated expiration: 2020-06-28

Abstract

The utility model discloses a high-power switching transformer which comprises a magnetic core, a magnetic core skeleton and a coil wound on the magnetic core skeleton, wherein the coil comprises a primary coil and a secondary coil; an insulating layer is wrapped between the primary coil and the secondary coil; the primary coil is divided into two parts which are respectively positioned in the inner layer and the outer layer of the coil; and the secondary coil is clamped between the two parts of the primary coil. The switching transformer can support quite high working efficiency and meet the design requirements of a high-power switching power supply which is above 2KW. As the switching frequency of the transformer is improved, the needed magnetic core volume can become small, therefore, the size of the switching transformer can be greatly reduced, and the mounting layout of the switching transformer on a circuit board is convenient. The switching transformer has the advantages of high efficiency, small temperature rise and smaller generated electromagnetic interference, and when the switching transformer is applied to the circuit design of the high-power switching power supply, the control logic of the control loop of the high-power switching power supply can be ensured to be normal.

Description

A kind of high power switch transformer

Technical field

The utility model belongs to the transformer technology field, specifically, relates to a kind of switch transformer design that is applicable to high power switching power supply.

Background technology

We are referred to as high power switching power supply usually Switching Power Supply more than the 1KW.For present high power switching power supply, the switching frequency of its internal switch transformer is generally very low, usually less than 20KHz.Because the switching frequency of transformer is very low, therefore need the very wide control loop of design frequency band, cause the control problem of unstable thus easily.On the other hand,, therefore, cause the increase of power loss easily, cause the power supply superheating phenomenon because the switching frequency of transformer is lower.In addition, because this low-frequency switch transformer can produce serious electromagnetic interference EMI, therefore, cause the confusion of control loop control logic easily.

As everyone knows, under same power situation, the switching frequency of transformer is low more, and its needed core volume is just big more.Thereby cause the increase of switch transformer size.Generally, the switch transformer of power more than 1KW, when its operating frequency during less than 20KHz, since oversize, be difficult in the circuit board install.Therefore, how improving the switching frequency of high power switch transformer, to reduce the overall dimensions of transformer, make things convenient for the wires design of wiring board, is the subject matter that present Switching Power Supply manufacturing field needs to be resolved hurrily.

The utility model content

The utility model is in order to solve the existing problem that the switch transformer switching frequency is low, size is big, a kind of high power switch transformer of brand new is provided, be wound on the position relation of primary coil on the magnetic core skeleton and secondary coil by change, thereby improved the switching frequency of transformer, make that the size of transformer is reduced, temperature rise reduces.

In order to solve the problems of the technologies described above, the utility model is achieved by the following technical solutions:

A kind of high power switch transformer comprises magnetic core, magnetic core skeleton and is wound on coil on the magnetic core skeleton; Described coil comprises primary coil and secondary coil, is coated with insulating barrier between primary coil and the secondary coil; Wherein, described primary coil separated into two parts lays respectively at the internal layer and the skin of coil, and secondary coil is sandwiched between two parts primary coil.

Preferably, the coiling equal turn numbers of described two parts primary coil.

Further, described primary coil and secondary coil form by the stranded conductor system of twisting.

Wherein, described primary coil can be formed by 30 strands of leads system of twisting; Secondary coil can be formed by 20 strands of leads system of twisting.

Further again, between described primary coil and secondary coil, all be coated with dielectric layers, one deck screen and other dielectric layers successively.

In addition, can also coat one deck screen, to reduce the electromagnetic interference of switch transformer to external circuit in the outside of described coil.

Coiling for convenience, described two parts primary coil is drawn lead-in wire terminal and leading-out terminal respectively, and is in series by external wire.

Further again, the secondary coil that is sandwiched between two parts primary coil can be one group, also can be two groups; When two groups of secondary coils of coiling, should be coated with insulating barrier between two groups of secondary coils.

Further, it is two-layer that every group of secondary coil all can turn to, and is coated with insulating barrier between the two-layer secondary coil.

Compared with prior art, advantage of the present utility model and good effect are: switch transformer of the present utility model passes through the coiling at twice of its primary coil, and at the middle coiling secondary coil of the primary coil of twice coiling, the switch transformer of Xing Chenging not only can satisfy the designing requirement of the above high power switching power supply of 2KW thus, and can support very high operating frequency.Because the switching frequency of transformer improves, so its needed core volume can diminish, and can reduce the size of switch transformer so greatly, makes things convenient for its mounting arrangement in the circuit board.Switch transformer efficient height of the present utility model, temperature rise are little, and the electromagnetic interference that is produced is less, is applied in the circuit design of high power switching power supply, can guarantee that the control logic of its control loop is normal.

After reading the detailed description of the utility model execution mode in conjunction with the accompanying drawings, other characteristics of the present utility model and advantage will become clearer.

Description of drawings

Fig. 1 is the circuit theory diagrams of the switch transformer that proposes of the utility model;

Fig. 2 is the coil winding schematic diagram of the switch transformer that proposes of the utility model;

Fig. 3 is the pin schematic diagram of switch transformer shown in Figure 2.

Embodiment

Below in conjunction with accompanying drawing embodiment of the present utility model is done explanation in further detail.

Embodiment one, and the switch transformer of present embodiment comprises magnetic core, magnetic core skeleton 10 and be wound on chief components such as coil on the magnetic core skeleton 10 that wherein, the coil that is wound on the magnetic core skeleton comprises primary coil and secondary coil two parts.In order to improve the switching frequency of transformer, present embodiment is wound on the primary coil separated into two parts on the magnetic core skeleton at twice, and secondary coil is wound between two parts primary coil, and coats screen 5 between primary coil and secondary coil, as shown in Figure 2.Be internal layer and the skin that primary coil is positioned at whole winding, its

exit difference

1,3,2,4 is in conjunction with Fig. 1, shown in Figure 2.Wherein, 1,3 lead-in wire terminal and the leading-out terminals that are respectively the internal layer primary coil; 2,4 lead-in wire terminal and the leading-out terminals that are respectively outer primary coil; Two parts primary coil can be together in series by external wire, as shown in Figure 1 after transformer is welded on the circuit board.Secondary coil is positioned at the mid portion of whole winding, promptly is clipped between two parts primary coil, can coiling one group, also can coiling two groups, and Fig. 2 is the coiling position view of two groups of secondary coils of coiling.Wherein, 9,8 are respectively the lead-in wire terminal and the leading-out terminal of first group of secondary coil, in conjunction with Fig. 1, shown in Figure 2; 7,6 lead-in wire terminal and the leading-out terminals that are respectively second group of secondary coil; Two groups of secondary coils are isolated by insulating barrier 17.In the present embodiment, described secondary coil can turn to one deck on magnetic core skeleton 10, also can turn to two-layer.Two-layer as if turning to, then between two-layer secondary coil, need to add a layer insulating 16,18, to realize isolation, as shown in Figure 2.

In order to realize better isolating between primary coil and the secondary coil, present embodiment preferably all coats dielectric layers 12,14 successively between two groups of primary coils and secondary coil; One deck screen 5 and other dielectric layers 13,15, as shown in Figure 2.Certainly, described insulating barrier 12,14,13,15 also can be provided with one deck or more multi-layered, and present embodiment is not limited in above giving an example.

In the present embodiment, the magnetic core of switch transformer preferably adopts the horizontal magnetic core of the EE70B of Ferrite Material, and primary coil and secondary coil are preferably full on magnetic core skeleton 10, to reduce power loss.Wherein, the coiling number of turn that lays respectively at internal layer and outer field two groups of primary coils preferably equates, promptly when the coiling primary coil, half primary coil of coiling on magnetic core skeleton 10 earlier coats dielectric layers 12, one deck screen 5 and dielectric layers 13 in addition then; The coiling secondary coil then coats dielectric layers 15, one deck screen 5 and other dielectric layers 14 more again; Last again half primary coil in addition is wound on the magnetic core skeleton 10, and coats screen at its outermost layer, to reduce EMI, so, can guarantee two groups of primary coils all can on magnetic core skeleton 10, realize expiring around.

In the present embodiment, after described primary coil and secondary coil preferably adopt the multiply thin wire to twist to make one heavy gauge wire, on magnetic core skeleton 10, carry out coiling again.As a kind of embodiment, the thin wire that it is 0.36mm that described primary coil can the adopt 30 strands of diameters system of twisting forms; The thin wire that it is 0.36mm that secondary coil can the adopt 20 strands of diameters system of twisting forms.

Owing to can't add barricade, present embodiment all installs insulating tape or insulating sleeve 11 additional on the lead-in wire terminal of primary coil and secondary coil and leading-out terminal, as shown in Figure 2, and to guarantee electric clearance and creepage distance.

Fig. 3 is the lead-in wire terminal and the Pin locations schematic diagram of leading-out terminal on magnetic core skeleton 10 of two parts primary coil and two groups of secondary coils, its two groups of secondary winding can connect (promptly 7 pin connect 8 pin) improve output voltage, also can (promptly 7 pin connect 9 pin, and 6 pin connect 8 pin) in parallel improve output current.

The switch transformer switching frequency height of present embodiment, size are little; under the air blast cooling condition; even at full load; its temperature rise also is no more than 40 ℃; therefore; can satisfy the main loop design of high-frequency bridge switch power supply or semi-bridge switching voltage regulator well, reduce electromagnetic interference, guarantee the normal of circuit controls logic the switch power control loop.

Should be noted that; above-mentioned explanation is not to be to restriction of the present utility model; the utility model also is not limited in above-mentioned giving an example; variation, remodeling, interpolation or replacement that those skilled in the art are made in essential scope of the present utility model also should belong to protection range of the present utility model.

Claims

1. high power switch transformer comprises magnetic core, magnetic core skeleton and is wound on coil on the magnetic core skeleton; Described coil comprises primary coil and secondary coil, is coated with insulating barrier between primary coil and the secondary coil; It is characterized in that: described primary coil separated into two parts, lay respectively at the internal layer and the skin of coil, secondary coil is sandwiched between two parts primary coil.

2. high power switch transformer according to claim 1 is characterized in that: the coiling equal turn numbers of described two parts primary coil.

3. high power switch transformer according to claim 2 is characterized in that: described primary coil and secondary coil form by the stranded conductor system of twisting.

4. high power switch transformer according to claim 3 is characterized in that: described primary coil is formed by 30 strands of leads system of twisting; Secondary coil is formed by 20 strands of leads system of twisting.

5. high power switch transformer according to claim 1 is characterized in that: all be coated with dielectric layers, one deck screen and other dielectric layers between described primary coil and secondary coil successively.

6. high power switch transformer according to claim 1 is characterized in that: the external packets at described coil is covered with screen.

7. high power switch transformer according to claim 1 is characterized in that: described two parts primary coil is drawn lead-in wire terminal and leading-out terminal respectively, and is in series by external wire.

8. according to each described high power switch transformer in the claim 1 to 7, it is characterized in that: described secondary coil is one group, turns to two-layerly, is coated with insulating barrier between the two-layer secondary coil.

9. according to each described high power switch transformer in the claim 1 to 7, it is characterized in that: described secondary coil is two groups, is coated with insulating barrier between two groups of secondary coils.

10. high power switch transformer according to claim 9 is characterized in that: described two groups of secondary coils all turn to two-layer, are coated with insulating barrier between the two-layer secondary coil.