Half-bridge synchronous rectifier

Abstract

The utility model discloses a half-bridge type synchronous rectifier, which comprises a box body, two secondary MOS (Metal Oxide Semiconductor) rectifying plates are arranged in the box body, the two secondary MOS rectifying plates are arranged in parallel, and each secondary MOS rectifying plate is electrically connected with an isolation transformer; the isolation transformer is electrically connected with one end of the IGBT half-bridge inversion module, the IGBT half-bridge inversion module is provided with an electrolytic capacitor, and the other end of the IGBT half-bridge inversion module is electrically connected with the three-phase rectifier bridge; the three-phase rectifier bridge and the IGBT half-bridge inversion module are arranged on one side of the isolation transformer; the three-phase rectifier bridge is electrically connected with the circuit breaker, the circuit breaker and the control panel are electrically connected and are both arranged in a protection plate on one side of the box body, and a PWM speed regulation fan is arranged below the control panel and is electrically connected with the control panel. By adopting the half-bridge synchronous rectifier, the transformer can be manufactured more simply, the equipment integration level is high, the operation is stable, and the temperature drift is small during working.

Description

Technical Field

[0001] The utility model relates to the technical field of rectifiers, in particular to a half-bridge synchronous rectifier. Background Art

[0002] In the prior art, with the maturity of high-frequency switching devices and application technologies, they are being used more and more widely, especially the rectifier power supply technology. High-frequency switching power supply equipment is increasingly recognized by various industries for its advantages such as small size, light weight, low production cost and easy standardized production. However, in some low-voltage industries, especially in electroplating industries or experimental power supplies, the DC voltage used is very low, often within DC12V. The primary phase-shifted full-bridge circuit is used, and the transformer is difficult to make and the cost is high; the secondary rectification uses a fast recovery diode, and the operating efficiency of the equipment will be very low, affecting the user's operating cost.

[0003] At present, the primary of high-frequency low-voltage electrolytic rectifier is mostly a phase-shifted full-bridge circuit. The voltage on the primary side of the transformer is relatively high, and the voltage required on the secondary side is very low and the current is very large. Therefore, the transformer primary-to-secondary ratio is large, the number of turns on the secondary side is small, and the transformer leakage inductance is difficult to control. The manufacturing is difficult and the cost is high. The secondary rectification circuit mostly uses fast recovery diodes as rectification devices, but the operating efficiency is extremely low because the output voltage of the equipment is very low. Summary of the invention

[0004] The utility model aims to provide a half-bridge synchronous rectifier, which can make the transformer production simpler, with high equipment integration, stable operation and small temperature drift during operation.

[0005] To achieve the above-mentioned purpose, the utility model provides a half-bridge synchronous rectifier, including a box body, wherein two secondary MOS rectifier plates are arranged in the box body, the two secondary MOS rectifier plates are arranged in parallel and each of the secondary MOS rectifier plates is electrically connected to an isolation transformer; the isolation transformer is electrically connected to one end of an IGBT half-bridge inverter module, an electrolytic capacitor is arranged on the IGBT half-bridge inverter module and the other end of the IGBT half-bridge inverter module is electrically connected to a three-phase rectifier bridge; the three-phase rectifier bridge and the IGBT half-bridge inverter module are both arranged on one side of the isolation transformer; the three-phase rectifier bridge is electrically connected to a circuit breaker, the circuit breaker is electrically connected to a control board and both are arranged in a protective plate on one side of the box body, and a PWM speed regulating fan is arranged below the control board and is electrically connected to the control board.

[0006] Preferably, the side of the box body opposite to the protective plate is a ventilation plate.

[0007] Preferably, the ventilation plate is provided with power terminals, a DC output negative pole and a DC output positive pole; the power terminals are electrically connected to the circuit breaker; the DC output negative pole and the DC output positive pole are electrically connected to the two secondary MOS rectifier boards respectively.

[0008] Preferably, the secondary MOS rectifier board is provided with a rectifier MOS tube and a drive voltage limiting protection MOS tube; the rectifier circuit composed of a number of the rectifier MOS tubes and the drive voltage limiting protection MOS tube are both arranged on a PCB board, the drive voltage limiting protection MOS tube is electrically connected to the rectifier circuit, and the isolation transformer is electrically connected to the drive voltage limiting protection MOS tube.

[0009] Preferably, an interlocking signal terminal, a status indicator light and a push-pull handle are installed on the protection plate; the interlocking signal terminal and the status indicator light are electrically connected to the control board respectively.

[0010] Preferably, an air inlet is provided on the protective plate, and a filter is provided on the outer side of the air inlet.

[0011] Preferably, the PWM speed-regulating fan is arranged opposite to the filter screen, and there are at least two PWM speed-regulating fans.

[0012] Preferably, the isolation transformer is located above the secondary MOS rectifier board, and the isolation transformer includes a transformer connection bar, a magnetic core is arranged on the transformer connection bar, and a winding is wound around the magnetic core.

[0013] Therefore, the utility model adopts the above-mentioned half-bridge synchronous rectifier to achieve the following beneficial effects:

[0014] (1) The primary inverter circuit adopts a half-bridge circuit to reduce the primary voltage of the transformer, reduce the transformer ratio, and make the transformer simpler to manufacture.

[0015] (2) The secondary rectification circuit uses a rectifier MOS tube and a driver voltage limiting protection MOS tube in parallel in each branch, all of which are integrated on a PCB board, which improves the equipment integration and ensures the stability of operation.

[0016] (3) The PWM speed-controlled fan is used for heat dissipation, which keeps the operating temperature of the equipment within a reasonable range and reduces the temperature drift of the equipment.

[0017] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the internal structure of a half-bridge synchronous rectifier embodiment of the utility model;

[0019] Figure 2It is a three-dimensional structural schematic diagram of an embodiment of a half-bridge synchronous rectifier of the utility model;

[0020] Figure 3 It is a rear view schematic diagram of an embodiment of a half-bridge synchronous rectifier of the utility model;

[0021] Figure 4 It is a top view schematic diagram of a half-bridge synchronous rectifier embodiment of the utility model;

[0022] Figure 5 It is a three-dimensional structural diagram of the secondary MOS rectifier board;

[0023] Figure 6 It is a three-dimensional structural diagram of the isolation transformer;

[0024] Figure 7 The utility model is a circuit diagram of a half-bridge synchronous rectifier embodiment.

[0025] Reference numerals

[0026] 1. Box; 2. Three-phase rectifier bridge; 3. Control board; 4. Secondary MOS rectifier board; 41. Rectifier MOS tube; 42. Drive voltage limiting protection MOS tube; 43. PCB board; 5. Isolation transformer; 51. Transformer connection bar; 52. Magnetic core; 53. Winding; 6. IGBT half-bridge inverter module; 61. Electrolytic capacitor; 7. PWM speed regulating fan; 8. Circuit breaker; 9. Power terminal; 10. DC output negative pole; 11. DC output positive pole; 12. Protective plate; 13. Ventilation plate; 14. Push-pull handle; 15. Interlocking signal terminal; 16. Status indicator light; 17. Filter. DETAILED DESCRIPTION

[0027] The technical solution of the utility model is further described below through the accompanying drawings and embodiments.

[0028] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" and the like mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0029] Example

[0030] like Figure 1 As shown, the utility model provides a half-bridge synchronous rectifier, including a box 1, in which two secondary MOS rectifier plates 4 are arranged, the two secondary MOS rectifier plates 4 are arranged in parallel, and each secondary MOS rectifier plate 4 is electrically connected to an isolation transformer 5, so that the isolation transformer 5 and the secondary MOS rectifier plate 4 are connected in two groups in parallel. Among them, the isolation transformer 5 is located above the secondary MOS rectifier plate 4, and the isolation transformer 5 includes a transformer connection row 51, and a magnetic core 52 is arranged on the transformer connection row 51, and a winding 53 is wound on the magnetic core 52.

[0031] The isolation transformer 5 is electrically connected to one end of the IGBT half-bridge inverter module 6, an electrolytic capacitor 61 is provided on the IGBT half-bridge inverter module 6, and the other end of the IGBT half-bridge inverter module 6 is electrically connected to the three-phase rectifier bridge 2. The three-phase rectifier bridge 2 and the IGBT half-bridge inverter module 6 are both arranged on one side of the isolation transformer 5, the three-phase rectifier bridge 2 is electrically connected to the circuit breaker 8, the circuit breaker 8 is electrically connected to the control board 3 and both are arranged in the protective plate 12 on one side of the box body 1, and a PWM speed regulating fan 7 is provided below the control board 3 and is electrically connected to the control board 3.

[0032] An interlocking signal terminal 15 , a status indicator light 16 and a push-pull handle 14 are installed on the protection plate 12 . The interlocking signal terminal 15 and the status indicator light 16 are electrically connected to the control board 3 , respectively.

[0033] The protective plate 12 is provided with an air inlet, and a filter 17 is provided outside the air inlet to filter impurities in the air and prevent the impurities from easily entering the interior of the box 1. The PWM speed regulating fan 7 is arranged opposite to the filter 17, and there are at least two PWM speed regulating fans 7, which can accelerate the circulation of gas and improve the heat dissipation effect of the rectifier.

[0034] The side of the box body 1 opposite to the protection plate 12 is a ventilation plate 13, and the ventilation plate 13 is provided with a power terminal 9, a DC output negative electrode 10, and a DC output positive electrode 11. The power terminal 9 is electrically connected to the circuit breaker 8, and the DC output negative electrode 10 and the DC output positive electrode 11 are electrically connected to the two secondary MOS rectifier boards 4 respectively.

[0035] The secondary MOS rectifier board 4 is provided with a rectifier MOS tube 41 and a drive voltage limiting protection MOS tube 42. The rectifier circuit composed of a plurality of rectifier MOS tubes 41 and the drive voltage limiting protection MOS tube 42 are both provided on a PCB board 43. The drive voltage limiting protection MOS tube 42 is electrically connected to the rectifier circuit, and the isolation transformer 5 is electrically connected to the drive voltage limiting protection MOS tube 42. The on-off control of the rectifier MOS tube 41 can be directly completed without adding other circuits, which greatly improves the integration of the equipment and the current sharing effect of the rectifier MOS tube 41, making the equipment more stable in operation.

[0036] During use:

[0037] The AC signal enters the circuit breaker 8 through the power terminal 9 provided on one side of the box 1, and is rectified into a DC voltage through the three-phase rectifier bridge 2 to achieve AC / DC conversion. It is then converted into a high-frequency AC square wave voltage through the IGBT half-bridge inverter circuit of the IGBT half-bridge inverter module 6. The secondary rectification circuit of the isolation transformer 5 and the secondary MOS rectifier board 4 adopts two groups in parallel. After each group of transformers is isolated, the secondary side adopts multiple rectifier MOS tubes 41 in parallel to rectify and output a DC voltage.

[0038] Among them, the two isolation transformers 5 are connected in parallel in the primary and in parallel in the secondary after rectification, so that the secondary current of a single isolation transformer 5 is reduced, and the difficulty of making the transformer is reduced. At the same time, due to the increase of the secondary rectification branch, the number of the single branch secondary rectification MOS tube 41 can be reduced, and the current sharing effect of the rectification MOS tube 41 is improved.

[0039] The heat dissipation of the equipment adopts PWM speed regulating fan 7 to automatically adjust the fan speed according to the operating temperature and output current, so that the equipment always operates in a reasonable temperature range and reduces the temperature drift problem caused by excessive temperature changes.

[0040] Therefore, the utility model adopts the above-mentioned half-bridge synchronous rectifier, which can make the transformer production simpler, with high equipment integration, stable operation and small temperature drift during operation.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that they can still modify or replace the technical solution of the utility model with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the utility model.

Claims

1. A half-bridge synchronous rectifier, comprising a housing, characterized in that: Two secondary MOS rectifier plates are arranged in the box, the two secondary MOS rectifier plates are arranged in parallel and each of the secondary MOS rectifier plates is electrically connected to an isolation transformer; the isolation transformer is electrically connected to one end of the IGBT half-bridge inverter module, the IGBT half-bridge inverter module is provided with an electrolytic capacitor and the other end of the IGBT half-bridge inverter module is electrically connected to the three-phase rectifier bridge; the three-phase rectifier bridge and the IGBT half-bridge inverter module are both arranged on one side of the isolation transformer; the three-phase rectifier bridge is electrically connected to the circuit breaker, the circuit breaker is electrically connected to the control board and both are arranged in the protective plate on one side of the box, and a PWM speed regulating fan is arranged below the control board and is electrically connected to the control board.

2. A half-bridge synchronous rectifier according to claim 1, characterized in that: A side of the box body opposite to the protective plate is a ventilation plate.

3. A half-bridge synchronous rectifier according to claim 2, characterized in that: The ventilation plate is provided with a power connection terminal, a DC output negative electrode and a DC output positive electrode; the power connection terminal is electrically connected to the circuit breaker; the DC output negative electrode and the DC output positive electrode are electrically connected to the two secondary MOS rectifier boards respectively.

4. A half-bridge synchronous rectifier according to claim 1, characterized in that: The secondary MOS rectifier board is provided with a rectifier MOS tube and a drive voltage limiting protection MOS tube; the rectifier circuit composed of a number of the rectifier MOS tubes and the drive voltage limiting protection MOS tube are both arranged on a PCB board, the drive voltage limiting protection MOS tube is electrically connected to the rectifier circuit, and the isolation transformer is electrically connected to the drive voltage limiting protection MOS tube.

5. A half-bridge synchronous rectifier according to claim 1, characterized in that: The protection plate is provided with an interlocking signal terminal, a status indicator light and a push-pull handle; the interlocking signal terminal and the status indicator light are electrically connected to the control board respectively.

6. A half-bridge synchronous rectifier according to claim 1, characterized in that: The protective plate is provided with an air inlet, and a filter is provided on the outer side of the air inlet.

7. A half-bridge synchronous rectifier according to claim 6, characterized in that: The PWM speed regulating fan is arranged opposite to the filter screen, and there are at least two PWM speed regulating fans.

8. A half-bridge synchronous rectifier according to claim 1, characterized in that: The isolation transformer is located above the secondary MOS rectifier board. The isolation transformer comprises a transformer connection bar. A magnetic core is arranged on the transformer connection bar. A winding is wound around the magnetic core.

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