Switching power supply circuit of series transformer
By designing a series transformer and a synchronous rectifier circuit, the problems of increased transformer size and cost were solved, achieving efficient production and low-cost switching power supply circuit design.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-23
- Publication Date
- 2026-03-27
AI Technical Summary
In the prior art, as the output power increases, the size of the transformer and the diameter of the secondary winding increase, leading to production difficulties and increased costs. At the same time, the use of synchronous rectifier MOSFETs increases the risk of component failure.
The primary coil is divided into two groups and the secondary coil into four groups. After being connected in parallel, each group of coils carries 1/4 of the rated current. Synchronous rectification circuit and full-bridge drive circuit are used to reduce current and losses.
By refining the secondary wire diameter of the transformer and reducing the operating frequency of the MOSFET, production efficiency was improved and costs were reduced, while the probability of MOSFET failure was also decreased.
Smart Images
Figure CN224054097U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to switching power supply technical field especially relates to a switching power supply circuit of series connection type transformer. BACKGROUND
[0002] High frequency transformer will be used in switching power supply, but with the increase of output power, the size of transformer will also increase.
[0003] In prior art, taking switching power supply circuit of full bridge drive as an example, in order to reduce the wire diameter of secondary coil, the secondary winding is usually changed into two groups of same winding, and in order to improve output efficiency, synchronous rectification MOS is used at secondary end to reduce loss.
[0004] But there are two problems in the above prior art, one is that with the increase of output power, or the output power is unchanged and the output voltage is reduced, the output current will increase, which requires the size of transformer and the wire diameter of secondary winding to increase, with the increase of wire diameter of secondary winding, the winding of transformer is more difficult, and the cost will also increase greatly; the other is that the synchronous rectification MOS used at secondary end needs to use larger current specification, or use parallel MOS, but this causes the production cost to rise, and also because of the difference of internal resistance of MOS tube, the IDS of each tube is different, and long time use will cause component failure. SUMMARY
[0005] Therefore, the utility model provides a switching power supply circuit of series connection type transformer.
[0006] The utility model discloses a switching power supply circuit of series connection type transformer, including: first primary coil T1A, second primary coil T2A, first secondary coil T1B1, second secondary coil T1B2, third secondary coil T2B1 and fourth secondary coil T2B2;
[0007] First secondary coil T1B1 and second secondary coil T1B2 are the induction winding of first primary coil T1A, and first primary coil T1A, first secondary coil T1B1 and second secondary coil T1B2 constitute first transformer;
[0008] Third secondary coil T2B1 and fourth secondary coil T2B2 are the induction winding of second primary coil T2A, and second primary coil T2A, third secondary coil T2B1 and fourth secondary coil T2B2 constitute second transformer;
[0009] First primary coil T1A and second primary coil T2A are in series connection;
[0010] The first secondary coil T1B1, the second secondary coil T1B2, the third secondary coil T2B1 and the fourth secondary coil T2B2 are respectively arranged in parallel after rectification.
[0011] As a preferred embodiment of the utility model, the wire diameter, the turn ratio and the inductance parameter of the first transformer and the second transformer correspond to the same respectively.
[0012] As a preferred embodiment of the utility model, the first primary coil T1A and the second primary coil T2A are connected with a primary drive circuit.
[0013] As a preferred embodiment of the utility model, the primary drive circuit is a primary full-bridge drive circuit.
[0014] The primary full-bridge drive circuit includes MOS tube Q8, MOS tube Q9, MOS tube Q10 and MOS tube Q11.
[0015] As a preferred embodiment of the utility model, the MOS tube Q8, the MOS tube Q9, the MOS tube Q10 and the MOS tube Q11 are all N channel MOS tubes.
[0016] As a preferred embodiment of the utility model, the G pole of the MOS tube Q10 is connected with G2 drive end, the S pole is grounded, and the D pole is connected with the S pole of the MOS tube Q9.
[0017] The G pole of the MOS tube Q9 is connected with G1 drive end, and the D pole is connected with HV interface and the D pole of the MOS tube Q11 simultaneously.
[0018] The G pole of the MOS tube Q11 is connected with G3 drive end, and the S pole is connected with the D pole of the MOS tube Q8.
[0019] The G pole of the MOS tube Q8 is connected with G4 drive end, and the S pole is grounded.
[0020] As a preferred embodiment of the utility model, the same name end of the first primary coil T1A is connected with the D pole of the MOS tube Q10 through a first filter circuit, and the different name end of the first primary coil T1A is connected with the same name end of the second primary coil T2A.
[0021] The different name end of the second primary coil T2A is connected with the D pole of the MOS tube Q8.
[0022] The D pole of the MOS tube Q9 is also connected with a second filter circuit.
[0023] As a preferred embodiment of the utility model, a secondary synchronous rectification circuit is further included.
[0024] The secondary synchronous rectification circuit comprises MOS tube Q12, MOS tube Q13, MOS tube Q14 and MOS tube Q15.
[0025] As a preferred embodiment of the utility model,
[0026] The G pole of the MOS tube Q13 is connected to the G1S drive end, the S pole is simultaneously connected to the negative pole of electrolytic capacitor CE12 and the ground, and the D pole is connected to the same name end of the first secondary coil T1B1.
[0027] The positive pole of the electrolytic capacitor CE12 is connected to the different name end of the first secondary coil T1B1.
[0028] The G pole of the MOS tube Q12 is connected to the G3S drive end, the S pole is simultaneously connected to the negative pole of electrolytic capacitor CE13 and the ground, and the D pole is connected to the different name end of the second secondary coil T1B2.
[0029] The positive pole of the electrolytic capacitor CE12 is connected to the same name end of the second secondary coil T1B2.
[0030] The different name end of the first secondary coil T1B1 is also connected to the same name end of the second secondary coil T1B2.
[0031] The G pole of the MOS tube Q15 is connected to the G3S drive end, the S pole is simultaneously connected to the negative pole of electrolytic capacitor CE14 and the ground, and the D pole is connected to the same name end of the third secondary coil T2B1.
[0032] The positive pole of the electrolytic capacitor CE14 is connected to the different name end of the third secondary coil T2B1.
[0033] The G pole of the MOS tube Q14 is connected to the G4S drive end, the S pole is simultaneously connected to the negative pole of electrolytic capacitor CE15 and the ground, and the D pole is connected to the different name end of the fourth secondary coil T2B2.
[0034] The positive pole of the electrolytic capacitor CE15 is connected to the same name end of the fourth secondary coil T2B2.
[0035] The different name end of the third secondary coil T2B1 is also connected to the same name end of the fourth secondary coil T2B2.
[0036] As a preferred embodiment of the utility model, the primary full-bridge drive circuit further comprises resistor R83, resistor R84, resistor R85 and resistor R86.
[0037] One end of the resistor R83 is grounded, and the other end is connected to the G1S drive end.
[0038] One end of the resistor R84 is grounded, and the other end is connected to the G3S drive end.
[0039] One end of the resistor R85 is grounded, and the other end is connected to the G4S driving end;
[0040] One end of the resistor R86 is grounded, and the other end is connected to the G2S driving end.
[0041] Compared with the prior art, the utility model has the following beneficial effects:
[0042] According to the technical scheme, when the first primary coil T1A and the second primary coil T2A have voltage passing through the respective magnetic cores, the respective two secondary windings are inducted, that is, the first secondary coil T1B1 and the second secondary coil T1B2, the third secondary coil T2B1 and the fourth secondary coil T2B2, each secondary coil only bears 1 / 4 rated current, according to P=I2R, the transformer secondary wire diameter at the time can use thinner copper wire, thereby improving the transformer production efficiency; meanwhile, the size of the transformer can use more common specifications, thereby reducing the cost. In addition, each secondary coil winding uses one MOS tube, which can reduce the probability of MOS tube damage. BRIEF DESCRIPTION OF DRAWINGS
[0043] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiment or the prior art description will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to the structure shown in the drawings without creative labor.
[0044] Figure 1 It is a circuit diagram of a series transformer switching power supply circuit of an embodiment of the utility model. DETAILED DESCRIPTION
[0045] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model, obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments, based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.
[0046] Embodiment:
[0047] As Figure 1The utility model discloses an embodiment provides a switch power supply circuit of series type transformer, comprising: first primary coil T1A, second primary coil T2A, first secondary coil T1B1, second secondary coil T1B2, third secondary coil T2B1 and fourth secondary coil T2B2,
[0048] First secondary coil T1B1 and second secondary coil T1B2 are the induction winding of first primary coil T1A, and first primary coil T1A, first secondary coil T1B1 and second secondary coil T1B2 constitute first transformer.
[0049] Third secondary coil T2B1 and fourth secondary coil T2B2 are the induction winding of second primary coil T2A, and second primary coil T2A, third secondary coil T2B1 and fourth secondary coil T2B2 constitute second transformer.
[0050] First primary coil T1A and second primary coil T2A are in series.
[0051] First secondary coil T1B1, second secondary coil T1B2, third secondary coil T2B1 and fourth secondary coil T2B2 are arranged in parallel after rectification.
[0052] The utility model discloses an embodiment through above-mentioned technical scheme's setting, when first primary coil T1A and second primary coil T2A have voltage through, through respective magnetic core, induction to respective two secondary windings, respectively first secondary coil T1B1 and second secondary coil T1B2, third secondary coil T2B1 and fourth secondary coil T2B2, above-mentioned every secondary coil only bears 1 / 4 rated current, according to P=I 2 R, the transformer secondary line diameter of this time can use thinner copper wire, thereby improves transformer production efficiency, and the size of transformer can use more commonly used specification and model, thereby reduces its cost.
[0053] As a preferred embodiment of the utility model, the wire diameter, the number of turns and the inductance parameters of the first transformer and the second transformer correspond to the same, respectively. Specifically, the wire diameter and the number of turns of the first primary coil T1A and the second primary coil T2A are the same; the wire diameter and the number of turns of the first secondary coil T1B1, the second secondary coil T1B2, the third secondary coil T2B1 and the fourth secondary coil T2B2 are the same; and the magnetic cores and the like used by the first transformer and the second transformer are the same.
[0054] As a preferred embodiment of the utility model, the first primary coil T1A and the second primary coil T2A are connected to a primary driving circuit. The primary driving circuit can be a half-bridge drive or a full-bridge drive. In the utility model, a full-bridge driving circuit is preferably used as the primary driving circuit in the circuit.
[0055] As a preferred embodiment of the utility model, the primary drive circuit is a primary full-bridge drive circuit.
[0056] The primary full-bridge drive circuit includes MOS tube Q8, MOS tube Q9, MOS tube Q10 and MOS tube Q11.
[0057] As a preferred embodiment of the utility model, the MOS tube Q8, MOS tube Q9, MOS tube Q10 and MOS tube Q11 are all N channel MOS tubes.
[0058] Wherein, MOS tube Q8, MOS tube Q9, MOS tube Q10 and MOS tube Q11 are all G pole drive, D pole high level.
[0059] As a preferred embodiment of the utility model, the G pole of MOS tube Q10 is connected with G2 drive end, S pole is grounded, and D pole is connected with the S pole of MOS tube Q9.
[0060] The G pole of MOS tube Q9 is connected with G1 drive end, and D pole is connected with HV interface and the D pole of MOS tube Q11 simultaneously.
[0061] The G pole of MOS tube Q11 is connected with G3 drive end, and S pole is connected with the D pole of MOS tube Q8.
[0062] The G pole of MOS tube Q8 is connected with G4 drive end, and S pole is grounded.
[0063] G1 drive end, G2 drive end, G3 drive end, G4 drive end input the output signal of full-bridge drive.
[0064] As a preferred embodiment of the utility model, the same name end of first primary coil T1A is connected with the D pole of MOS tube Q10 through first filter circuit, and the different name end of first primary coil T1A is connected with the same name end of second primary coil T2A.
[0065] The different name end of second primary coil T2A is connected with the D pole of MOS tube Q8.
[0066] The D pole of MOS tube Q9 is also connected with second filter circuit.
[0067] Wherein, the first filter circuit includes capacitor C42 and capacitor C43, one end of capacitor C42 and one end of capacitor C43 are both connected with the same name end of first primary coil T1A, and the other end of capacitor C42 and the other end of capacitor C43 are both connected with the D pole of MOS tube Q10.
[0068] The second filter circuit comprises a capacitor C44 and a capacitor C45, one end of the capacitor C44 and one end of the capacitor C45 are connected to the D pole of the MOS tube Q9, and the other end of the capacitor C44 and the other end of the capacitor C45 are grounded.
[0069] As a preferred embodiment of the utility model, the secondary synchronous rectification circuit is further included.
[0070] The secondary synchronous rectification circuit comprises a MOS tube Q12, a MOS tube Q13, a MOS tube Q14 and a MOS tube Q15.
[0071] The MOS tube Q12, the MOS tube Q13, the MOS tube Q14 and the MOS tube Q15 are all G pole driven and D pole high level.
[0072] As a preferred embodiment of the utility model,
[0073] The G pole of the MOS tube Q13 is connected to the G2S driving end, the S pole is connected to the negative pole of an electrolytic capacitor CE12 and the ground at the same time, and the D pole is connected to the same name end of the first secondary coil T1B1.
[0074] The positive pole of the electrolytic capacitor CE12 is connected to the different name end of the first secondary coil T1B1.
[0075] The G pole of the MOS tube Q12 is connected to the G1S driving end, the S pole is connected to the negative pole of an electrolytic capacitor CE13 and the ground at the same time, and the D pole is connected to the different name end of the second secondary coil T1B2.
[0076] The positive pole of the electrolytic capacitor CE12 is connected to the same name end of the second secondary coil T1B2.
[0077] The different name end of the first secondary coil T1B1 is further connected to the same name end of the second secondary coil T1B2.
[0078] The G pole of the MOS tube Q15 is connected to the G3S driving end, the S pole is connected to the negative pole of an electrolytic capacitor CE14 and the ground at the same time, and the D pole is connected to the same name end of the third secondary coil T2B1.
[0079] The positive pole of the electrolytic capacitor CE14 is connected to the different name end of the third secondary coil T2B1.
[0080] The G pole of the MOS tube Q14 is connected to the G4S driving end, the S pole is connected to the negative pole of an electrolytic capacitor CE15 and the ground at the same time, and the D pole is connected to the different name end of the fourth secondary coil T2B2.
[0081] The positive pole of the electrolytic capacitor CE15 is connected to the same name end of the fourth secondary coil T2B2.
[0082] The opposite end of the third secondary coil T2B1 is also connected to the same end of the fourth secondary coil T2B2.
[0083] As a preferred embodiment of the utility model, the primary full-bridge drive circuit further comprises resistors R83, R84, R85 and R86;
[0084] One end of the resistor R83 is grounded, and the other end is connected to the G1S drive end;
[0085] One end of the resistor R84 is grounded, and the other end is connected to the G3S drive end;
[0086] One end of the resistor R85 is grounded, and the other end is connected to the G4S drive end;
[0087] One end of the resistor R86 is grounded, and the other end is connected to the G2S drive end.
[0088] Through the above technical solution, each secondary coil induces voltage and passes through synchronous rectification, then passes through electrolytic capacitors CE12, CE13, CE14 and CE15, thereby outputting DC constant voltage. Each secondary coil winding uses one MOS tube, which can reduce the probability of MOS tube damage.
[0089] Compared with the prior art, the utility model has the following beneficial effects:
[0090] In the embodiment of the utility model, when the first primary coil T1A and the second primary coil T2A have voltage passing through, the voltage passes through the respective magnetic cores and induces two secondary windings, i.e. the first secondary coil T1B1 and the second secondary coil T1B2, the third secondary coil T2B1 and the fourth secondary coil T2B2. Each secondary coil induces voltage and passes through synchronous rectification, then passes through electrolytic capacitors CE12, CE13, CE14 and CE15, thereby outputting DC constant voltage. In the above process, each secondary coil only bears 1 / 4 of the rated current. According to P=I²R, the transformer secondary line diameter can use thinner copper wire, thereby improving the transformer production efficiency; at the same time, the size of the transformer can use more common specifications, thereby reducing the cost. In addition, each secondary coil winding uses one MOS tube, which can reduce the probability of MOS tube damage.
[0091] The above merely describes preferred embodiments of the present utility model patent, but the protection scope of the present utility model patent is not limited thereto, and any person skilled in the art, within the scope disclosed by the present utility model patent, can make equivalent replacements or changes to the technical scheme and the utility model concept of the present utility model patent, and all of them belong to the protection scope of the present utility model patent.
Claims
1. A switching power supply circuit of a series type transformer, characterized by comprising: Comprise: The first primary coil T1A, the second primary coil T2A, the first secondary coil T1B1, the second secondary coil T1B2, the third secondary coil T2B1 and the fourth secondary coil T2B2; The first secondary coil T1B1 and the second secondary coil T1B2 are the induced winding of the first primary coil T1A, and the first primary coil T1A, the first secondary coil T1B1 and the second secondary coil T1B2 constitute a first transformer; The third secondary coil T2B1 and the fourth secondary coil T2B2 are the induced winding of the second primary coil T2A, and the second primary coil T2A, the third secondary coil T2B1 and the fourth secondary coil T2B2 constitute a second transformer; The first primary coil T1A and the second primary coil T2A are connected in series; The first secondary coil T1B1, the second secondary coil T1B2, the third secondary coil T2B1 and the fourth secondary coil T2B2 are respectively arranged in parallel after rectification.
2. The switching power supply circuit of a series type transformer according to claim 1, characterized by The wire diameter, turn ratio and inductance parameters of the first transformer and the second transformer correspond to each other.
3. The switching power supply circuit of a serial type transformer according to claim 1, characterized by The first primary coil T1A and the second primary coil T2A are connected to a primary driving circuit.
4. The switching power supply circuit of a serial type transformer according to claim 3, characterized by The primary driving circuit is a primary full-bridge driving circuit; The primary full-bridge driving circuit comprises MOS tubes Q8, Q9, Q10 and Q11.
5. The switching power supply circuit of a series type transformer according to claim 4, characterized by The MOS tubes Q8, Q9, Q10 and Q11 are all N-channel MOS tubes.
6. The switching power supply circuit of the series transformer according to claim 5, wherein The G pole of the MOS tube Q10 is connected to the G2 driving end, the S pole is grounded, and the D pole is connected to the S pole of the MOS tube Q9; The G pole of the MOS tube Q9 is connected to the G1 driving end, and the D pole is connected to the HV interface and the D pole of the MOS tube Q11 at the same time; The G pole of the MOS tube Q11 is connected to the G3 driving end, and the S pole is connected to the D pole of the MOS tube Q8; The G pole of the MOS tube Q8 is connected to the G4 driving end, and the S pole is grounded.
7. The switching power supply circuit of the series transformer according to claim 6, wherein The same name end of the first primary coil T1A is connected to the D pole of the MOS tube Q10 through a first filter circuit, and the opposite name end of the first primary coil T1A is connected to the same name end of the second primary coil T2A; The opposite name end of the second primary coil T2A is connected to the D pole of the MOS tube Q8; The D pole of the MOS tube Q9 is also connected to a second filter circuit.
8. The switching power supply circuit of a serial type transformer according to claim 4, characterized by It also comprises a secondary synchronous rectification circuit; The secondary synchronous rectification circuit comprises MOS tubes Q12, Q13, Q14 and Q15.
9. The switching power supply circuit of the series transformer according to claim 8, wherein The G pole of the MOS tube Q13 is connected to the G2S driving end, the S pole is connected to the negative pole of the electrolytic capacitor CE12 and grounded at the same time, and the D pole is connected to the same name end of the first secondary coil T1B1; The positive pole of the electrolytic capacitor CE12 is connected to the opposite name end of the first secondary coil T1B1; The G pole of the MOS tube Q12 is connected to the G1S driving end, the S pole is connected to the negative pole of the electrolytic capacitor CE13 and the ground, and the D pole is connected to the opposite-phase end of the second secondary coil T1B2; The positive pole of the electrolytic capacitor CE12 is connected to the same-phase end of the second secondary coil T1B2; The opposite-phase end of the first secondary coil T1B1 is also connected to the same-phase end of the second secondary coil T1B2; The G pole of the MOS tube Q15 is connected to the G3S driving end, the S pole is connected to the negative pole of the electrolytic capacitor CE14 and the ground, and the D pole is connected to the same-phase end of the third secondary coil T2B1; The positive pole of the electrolytic capacitor CE14 is connected to the opposite-phase end of the third secondary coil T2B1; The G pole of the MOS tube Q14 is connected to the G4S driving end, the S pole is connected to the negative pole of the electrolytic capacitor CE15 and the ground, and the D pole is connected to the opposite-phase end of the fourth secondary coil T2B2; The positive pole of the electrolytic capacitor CE15 is connected to the same-phase end of the fourth secondary coil T2B2; The opposite-phase end of the third secondary coil T2B1 is also connected to the same-phase end of the fourth secondary coil T2B2.
10. The switching power supply circuit of a series type transformer according to claim 9, wherein The primary full-bridge driving circuit further comprises resistors R83, R84, R85 and R86; One end of the resistor R83 is grounded, and the other end is connected to the G1S driving end; One end of the resistor R84 is grounded, and the other end is connected to the G3S driving end; One end of the resistor R85 is grounded, and the other end is connected to the G4S driving end; One end of the resistor R86 is grounded, and the other end is connected to the G2S driving end.