CN213151912U

CN213151912U - High-power phase-shifted full-bridge circuit based on twin-coil follow current inductor

Info

Publication number: CN213151912U
Application number: CN202021445779.5U
Authority: CN
Inventors: 王建廷; 杨俊锋; 肖科明; 邓鸿国; 覃辉龙
Original assignee: Shenzhen Lianming Power Co ltd
Current assignee: Shenzhen Lianming Power Supply Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2021-05-07
Anticipated expiration: 2030-07-21

Abstract

The utility model discloses a high-power phase-shifting full-bridge circuit based on twin coil afterflow inductance, wherein: the two ends of the secondary winding of the first transformer are respectively connected to the anode of the first diode and the anode of the second diode, the cathode of the first diode and the cathode of the second diode are both connected to the first end of the first coil, the two ends of the secondary winding of the second transformer are respectively connected to the anode of the third diode and the anode of the fourth diode, the cathode of the third diode and the cathode of the fourth diode are both connected to the first end of the second coil, the second end of the first coil and the second end of the second coil are connected with each other and then serve as the output end of the high-power phase-shifting full-bridge circuit, and the middle tap of the secondary winding of the first transformer and the middle tap of the secondary winding of the second transformer are connected with each other and then serve as the grounding end of the. The utility model discloses enable two transformer power distribution balanced, avoid transformer secondary winding current unbalance.

Description

High-power phase-shifted full-bridge circuit based on twin-coil follow current inductor

Technical Field

The utility model relates to a high-power phase-shifting full-bridge circuit especially relates to a high-power phase-shifting full-bridge circuit based on twin coil afterflow inductance.

Background

At present, in a common phase-shifted full-bridge circuit, a rectification/follow-current mode that a single transformer corresponds to a pair of output windings and a follow-current inductor is generally adopted for low power, and the problem of secondary current balance degree does not exist in the application mode. However, when the output power is large and limited by the volume of the equipment, the power output of a single transformer becomes insufficient, and as the volume of the transformer increases, the following problems are caused: first, the core utilization will be low; secondly, the coil in the transformer winding is not easy to radiate, the window area of the magnetic core is large, heat generated by the coil in the transformer winding needs to be conducted to the surface, and the heat in the coil is not easy to be transferred to the surface, so that the internal temperature is high; thirdly, the winding process of the transformer is relatively complex, the larger the coil is, the thicker the wire diameter is, and the more difficult the winding process and installation are.

In the prior art, a phase-shifted full-bridge circuit with the same power output can adopt a design mode of double transformers, so that the defects caused by a single-transformer mode can be avoided, please refer to fig. 1, fig. 2 and fig. 3, the leading and lagging bridge arms of the phase-shifted full-bridge circuit are formed by connecting primary windings T1A and T2A of two transformers T1 and T2 in series, a resonant inductor L1, a balance capacitor C1 and four MOSFETs on the bridge arms, and the problem of current imbalance is solved without changing the circuits of the primary part. The secondary windings of the transformers T1 and T2 are rectified by diodes D1, D2, D3 and D4 and then connected to the S end of a freewheeling inductor L2, and the tail end F of the freewheeling inductor L2 is filtered by capacitors E1, E2 and E3 and then connected to the electric equipment. Based on the circuit principle, the two-transformer mode adopted in the industry at present is to connect the primary windings of two transformers in series, connect the secondary windings in parallel, and follow current through the same inductor after rectification, and the wiring mode solves the problems of heat dissipation and winding of the transformers, but brings the phenomenon of unbalanced current of the secondary windings of the transformers. However, in the application of the dual-transformer phase-shifted full bridge, the unbalanced current of the secondary winding of the transformer can cause uneven power distribution of the two transformers; the temperature rise of the transformer generates difference; and the turn-off spikes of the rectifier diodes are not uniform.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model lies in, to prior art not enough, provide one kind and enable two transformer power distribution balanced, avoid transformer secondary winding unbalanced current based on the high-power phase-shifting full-bridge circuit of twin coil afterflow inductance.

In order to solve the technical problem, the utility model adopts the following technical scheme.

A high-power phase-shifting full-bridge circuit based on a double-coil follow current inductor comprises a full-bridge input circuit, a first transformer, a second transformer, a first diode, a second diode, a third diode, a fourth diode and a follow current inductor, wherein the follow current inductor comprises a magnetic ring, and a first coil and a second coil wound on the magnetic ring, the first end of a primary winding of the first transformer and the second end of a primary winding of the second transformer are respectively connected with the output end of the full-bridge input circuit, the second end of the primary winding of the first transformer and the first end of the primary winding of the second transformer are mutually connected, the two ends of a secondary winding of the first transformer are respectively connected with the anode of the first diode and the anode of the second diode, and the cathode of the first diode and the cathode of the second diode are both connected with the first end of the first coil, the both ends of second transformer secondary winding connect respectively in the positive pole of third diode with the positive pole of fourth diode, the negative pole of third diode with the negative pole of fourth diode all connect in the first end of second coil, the second end of first coil with regard as behind the second end interconnect of second coil the output of high-power phase-shifting full-bridge circuit, the center tap of first transformer secondary winding with regard as behind the center tap interconnect of second transformer secondary winding the earthing terminal of high-power phase-shifting full-bridge circuit output side.

Preferably, the first coil and the second coil are respectively wound on the left half part and the right half part of the magnetic ring.

Preferably, the first end of the first coil and the first end of the second coil are both led out from one side of the magnetic ring, and the second end of the first coil and the second end of the second coil are both led out from the other side of the magnetic ring.

Preferably, three capacitors connected in parallel are connected between the output end and the ground end of the high-power phase-shifted full bridge circuit.

Preferably, all three capacitors are electrolytic capacitors.

Preferably, the magnetic ring is a single magnetic ring body or consists of a plurality of magnetic ring bodies which are sequentially stacked.

The utility model discloses an in high-power phase-shifting full bridge circuit based on twin coil afterflow inductance, the afterflow inductance contains two independent first coils and second coil, carries out corresponding change with the method of connecing of afterflow inductance simultaneously, in the circuit course of operation, because first transformer, each winding of second transformer is the same with the name end order, thereby guaranteed first diode, third diode switch on/off simultaneously, second diode, fourth diode switch on/off simultaneously, first coil and second coil rectification/afterflow in the afterflow inductance simultaneously borrow by this first coil and the magnetic balance among the second coil course of operation and restrain the current mutation of any one in two coils, and then reach first transformer, the balanced purpose of second transformer secondary winding current, make two transformer power distribution balanced, effectively avoided two transformers to produce difference and diode turn-off the inconsistent condition of spike because of the temperature rise The application requirements are better met.

Drawings

FIG. 1 is a schematic diagram of a high power phase-shifted full bridge circuit in the prior art;

FIG. 2 is a schematic diagram of a freewheeling inductor in a conventional high-power phase-shifted full-bridge circuit;

FIG. 3 is a schematic diagram of a winding manner of a follow current inductor in a conventional high-power phase-shifted full-bridge circuit;

FIG. 4 is a schematic diagram of a high-power phase-shifted full-bridge circuit based on a twin-coil freewheeling inductor according to the present invention;

FIG. 5 is a schematic diagram of the follow current inductor in the high-power phase-shifted full-bridge circuit of the present invention;

fig. 6 is a schematic diagram of the winding mode of the follow current inductor in the high-power phase-shifted full-bridge circuit of the present invention.

Detailed Description

The present invention will be described in more detail with reference to the accompanying drawings and examples.

The utility model discloses a high-power phase-shifting full-bridge circuit based on twin coil freewheeling inductor, combine fig. 4 to fig. 6 to show, it includes full-bridge input circuit 1, first transformer T1, second transformer T2, first diode D1, second diode D2, third diode D3, fourth diode D4 and freewheeling inductor L2, freewheeling inductor L2 is including magnetic ring L2-3 and coiling in first coil L2-1 and second coil L2-2 on magnetic ring L2-3, the first end of first transformer T1 primary winding and the second end of second transformer T2 primary winding connect respectively in the output of full-bridge input circuit 1, the second end of first transformer T1 primary winding and the first end interconnect of second transformer T2 primary winding, the both ends of first transformer T1 secondary winding connect respectively in the positive pole of first diode D1 and the positive pole 2 of second diode D2, the cathode of the first diode D1 and the cathode of the second diode D2 are both connected to the first end of the first coil L2-1, two ends of the secondary winding of the second transformer T2 are respectively connected to the anode of the third diode D3 and the anode of the fourth diode D4, the cathode of the third diode D3 and the cathode of the fourth diode D4 are both connected to the first end of the second coil L2-2, the second end of the first coil L2-1 and the second end of the second coil L2-2 are connected to each other and then serve as the output end of the high-power phase-shift full bridge circuit, and the center tap of the secondary winding of the first transformer T1 and the center tap of the secondary winding of the second transformer T2 are connected to each other and then serve as the ground end of the output side of the high-power phase-shift full bridge circuit.

In the above circuit, the freewheeling inductor L2 includes two independent first and second coils L2-1 and L2-2, and the connection of the freewheeling inductor L2 is changed accordingly, in the working process of the circuit, because the same-name ends of the windings of the first and second transformers T1 and T2 are in the same order, it is ensured that the first and third diodes D1 and D3 are turned on/off at the same time, the second and fourth diodes D2 and D4 are turned on/off at the same time, the first and second coils L2-1 and L2-2 in the freewheeling inductor L2 rectify/freewheel at the same time, the current abrupt change of any one of the two coils is suppressed by the magnetic balance in the working process of the first and second coils L2-1 and L2-2, and the purpose of current balance of the secondary windings of the first and second transformers T1 and T2 is achieved, the power distribution of the two transformers is balanced, the conditions that the two transformers are different due to temperature rise and the turn-off peaks of the diodes are inconsistent are effectively avoided, and the application requirements are well met.

Referring to fig. 2 and 3, in a conventional winding manner of a follow current inductor, the requirement for the through flow of a wire diameter is high due to high output power, and n wires need to be wound in parallel for 360 degrees, which increases the difficulty in the winding process and the installation on a PCB.

In view of the above, referring to fig. 5 and 6, in the present invention, the first coil L2-1 and the second coil L2-2 are respectively wound around the left half and the right half of the magnetic ring L2-3.

That is to say, in this embodiment, the freewheeling inductor L2 divides the coil winding into two windings, that is, the first coil L2-1 and the second coil L2-2, each coil winding is reduced from the conventional n to n/2, and the wire diameter of each coil winding is also reduced by half, and a single coil winding is wound by 180 degrees along the magnetic ring, so that the difficulty of the inductor in the winding process is greatly reduced, and the assembly work with the PCB is facilitated.

In order to facilitate wire connection and coil terminal identification, in this embodiment, the first end of the first coil L2-1 and the first end of the second coil L2-2 are both led out from one side of the magnetic ring L2-3, and the second end of the first coil L2-1 and the second end of the second coil L2-2 are both led out from the other side of the magnetic ring L2-3.

In order to perform the output side filtering function, in this embodiment, three capacitors E1, E2, and E3 connected in parallel are connected between the output end and the ground end of the high-power phase-shifted full-bridge circuit. Further, the three capacitors E1, E2, and E3 are all electrolytic capacitors.

In practical application, according to application requirements, the magnetic ring L2-3 may be a single magnetic ring body, or may be composed of a plurality of magnetic ring bodies stacked in sequence.

The above is only the embodiment of the present invention, and is not intended to limit the present invention, and all modifications, equivalent replacements or improvements made within the technical scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-power phase-shifting full-bridge circuit based on a dual-coil freewheeling inductor is characterized by comprising a full-bridge input circuit (1), a first transformer (T1), a second transformer (T2), a first diode (D1), a second diode (D2), a third diode (D3), a fourth diode (D4) and a freewheeling inductor (L2), wherein the freewheeling inductor (L2) comprises a magnetic ring (L2-3), a first coil (L2-1) and a second coil (L2-2) which are wound on the magnetic ring (L2-3), a first end of a primary winding of the first transformer (T1) and a second end of a primary winding of the second transformer (T2) are respectively connected to an output end of the full-bridge input circuit (1), a second end of the primary winding of the first transformer (T1) and a first end of a primary winding of the second transformer (T2) are connected with each other, two ends of a secondary winding of the first transformer (T1) are respectively connected to an anode of the first diode (D1) and an anode of the second diode (D2), a cathode of the first diode (D1) and a cathode of the second diode (D2) are both connected to a first end of the first coil (L2-1), two ends of a secondary winding of the second transformer (T2) are respectively connected to an anode of the third diode (D3) and an anode of the fourth diode (D4), a cathode of the third diode (D3) and a cathode of the fourth diode (D4) are both connected to a first end of the second coil (L2-2), a second end of the first coil (L2-1) and a second end of the second coil (L2-2) are connected to each other to serve as an output end of the high power circuit, a middle tap of the secondary winding of the first transformer (T1) and a secondary winding of the second transformer (T2) are connected to each other to serve as an output end of the high power circuit, and a phase shift circuit is connected to the second diode (T2) And the middle taps of the group are connected with each other and then are used as the grounding end of the output side of the high-power phase-shifted full-bridge circuit.

2. The high-power phase-shifted full-bridge circuit based on the dual-coil freewheeling inductor according to claim 1, wherein the first coil (L2-1) and the second coil (L2-2) are respectively wound around the left half and the right half of the magnetic ring (L2-3).

3. The high-power phase-shifted full-bridge circuit based on the dual-coil freewheeling inductor according to claim 2, wherein the first end of the first coil (L2-1) and the first end of the second coil (L2-2) are both led out from one side of the magnetic ring (L2-3), and the second end of the first coil (L2-1) and the second end of the second coil (L2-2) are both led out from the other side of the magnetic ring (L2-3).

4. High-power phase-shifted full-bridge circuit based on dual-coil freewheeling inductor according to claim 1, characterized in that three capacitors (E1, E2, E3) are connected in parallel between the output terminal and the ground terminal of the high-power phase-shifted full-bridge circuit.

5. The high-power phase-shifted full-bridge circuit based on the dual-coil freewheeling inductor according to claim 4, characterized in that the three capacitors (E1, E2, E3) are all electrolytic capacitors.

6. The high-power phase-shifted full-bridge circuit based on the dual-coil freewheeling inductor as claimed in claim 1, wherein the magnetic ring (L2-3) is a single magnetic ring body or is composed of a plurality of magnetic ring bodies stacked in sequence.