CN207910685U - Tri-level half-bridge Sofe Switch convertor circuit, welding machine, electrolysis water power supply and charger - Google Patents

Tri-level half-bridge Sofe Switch convertor circuit, welding machine, electrolysis water power supply and charger Download PDF

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Publication number
CN207910685U
CN207910685U CN201820243972.7U CN201820243972U CN207910685U CN 207910685 U CN207910685 U CN 207910685U CN 201820243972 U CN201820243972 U CN 201820243972U CN 207910685 U CN207910685 U CN 207910685U
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circuit
switching tube
tri
bridge
level half
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张光先
李�昊
边乐民
张甫国
刘月
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SHANDONG AOTAI ELECTRIC CO Ltd
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SHANDONG AOTAI ELECTRIC CO Ltd
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

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Abstract

The utility model discloses a kind of tri-level half-bridge Sofe Switch convertor circuits, including inputting bleeder circuit, tri-level half-bridge inverter circuit, transformer and output circuit, the input bleeder circuit is in parallel with tri-level half-bridge inverter circuit, the tri-level half-bridge inverter circuit includes switching tube bridge arm circuit and switching tube clamp circuit, switching tube clamp circuit midpoint is connected with input bleeder circuit midpoint, the transformer primary side, pulsactor and capacitance series connection, one end is connected with switching tube bridge arm circuit midpoint after series connection, the other end is connected with input bleeder circuit midpoint, the transformer secondary is connected with output circuit.The utility model can make each switching tube be in Sofe Switch state when shutdown is connected by pulsactor and capacitance.

Description

Tri-level half-bridge Sofe Switch convertor circuit, welding machine, electrolysis water power supply and charger
Technical field
The utility model is related to DC-AC-DC convertor circuits fields, and in particular to a kind of tri-level half-bridge Sofe Switch change galvanic electricity Road, welding machine, electrolysis water power supply and charger.
Background technology
Two traditional level convertor circuits, have many advantages, such as that topological structure is simple, easily controllable, are widely used in various In DC-AC-DC convertor circuits.But there is also switching tube pressure voltages to require height for two level convertor circuits, and switch stress is big, frequency The problems such as difficult is promoted, occasion is inputted in high voltage, receives larger limitation.Three-level inverter circuit bears electricity due to switching tube Pressure value is the half of two level inverter circuits, and switch stress is small, it is easier to realize high frequency, in the case where high voltage inputs occasion, and application It is with the obvious advantage.
Conventional tri-level half-bridge inversion topological mostly uses the on-off mode of hard switching, and switching loss is larger, limits switch The further promotion of frequency.Although Chinese patent 102255548A uses the topological form of Sofe Switch, but each switching tube is closing It is hard shutdown when disconnected, is merely able to realize that no-voltage conducting, Sofe Switch effect are poor.
Utility model content
In order to solve the above-mentioned technical problem, the utility model provides a kind of tri-level half-bridge Sofe Switch convertor circuit, should Circuit can make each switching tube be in Sofe Switch state when shutdown is connected, and provide mechanical, electrical using the weldering of foregoing circuit Xie Shui electricity Yuan and charger.
To achieve the goals above, the technical solution of the utility model is as follows:
A kind of tri-level half-bridge Sofe Switch convertor circuit, including input bleeder circuit, tri-level half-bridge inverter circuit, transformation Device, pulsactor, capacitance and output circuit, the input bleeder circuit is in parallel with tri-level half-bridge inverter circuit, described Tri-level half-bridge inverter circuit includes switching tube bridge arm circuit and switching tube clamp circuit, switching tube clamp circuit midpoint with Input bleeder circuit midpoint to be connected, the transformer primary side, pulsactor and capacitance series connection, after series connection one end with it is described Switching tube bridge arm circuit midpoint is connected, and the other end is connected with input bleeder circuit midpoint, the transformer secondary and output circuit It is connected.
Further, the input bleeder circuit includes 2 input capacitances, and the input capacitance is connected in series with.
Further, the switching tube bridge arm circuit includes bridge under bridge arm circuit and switching tube on the switching tube being connected in series with Arm circuit, switching tube clamp circuit one end are connected with bridge arm midpoint on switching tube, the other end and switching tube lower bridge arm midpoint It is connected.
Further, the switching tube bridge arm circuit includes 4 switching tubes for carrying anti-paralleled diode, the switching tube It is sequentially connected in series, both the above switching tube forms bridge arm on switching tube, and following two switching tube forms switching tube lower bridge arm.
Further, the switching tube clamp circuit includes 2 clamp diodes, and the clamp diode is connected in series with.
Further, each switching tube both ends of the tri-level half-bridge inverter circuit are parallel with capacitance respectively.
Further, the clamp circuit both ends have been arranged in parallel striding capacitance.
A kind of welding machine, including any tri-level half-bridge Sofe Switch convertor circuit as described above.
A kind of electrolysis water power supply, including any tri-level half-bridge Sofe Switch convertor circuit as described above.
A kind of charger, including any tri-level half-bridge Sofe Switch convertor circuit as described above.
Compared with prior art, the utility model has the beneficial effects that:
The utility model provides a kind of tri-level half-bridge Sofe Switch convertor circuit, and each switching tube can be made to be turned off in conducting When be in Sofe Switch state;
The utility model can be by input capacitance voltage clamping using the partial switch pipe of tri-level half-bridge inverter circuit Characteristic, the effect of each switching tube dynamic electric voltage clamper is realized by control method, meanwhile, coordinate pulsactor and capacitance Realize the effect of Sofe Switch.
Description of the drawings
The accompanying drawings which form a part of this application are used for providing further understanding of the present application, and the application's shows Meaning property embodiment and its explanation do not constitute the improper restriction to the application for explaining the application.
Fig. 1 is a kind of tri-level half-bridge Sofe Switch convertor circuit typical topology schematic diagram of the utility model;
Fig. 2 is the circuit diagram of the utility model embodiment 2;
Fig. 3 is the circuit diagram of the utility model embodiment 3;
Fig. 4 is each switching tube on, off sequence diagram of the utility model;
Fig. 5 is 1 stage of operating mode equivalent circuit and current loop figure under the utility model typical topology;
Fig. 6 is 2 stage of operating mode equivalent circuit and current loop figure under the utility model typical topology;
Fig. 7 is 3 stage of operating mode equivalent circuit and current loop figure under the utility model typical topology;
Fig. 8 is 4 stage of operating mode equivalent circuit and current loop figure under the utility model typical topology;
Fig. 9 is 5 stage of operating mode equivalent circuit and current loop figure under the utility model typical topology.
Specific implementation mode
The utility model is described further with specific embodiment below in conjunction with the accompanying drawings.
It is noted that following detailed description is all illustrative, it is intended to provide further instruction to the application.Unless another It indicates, all technical and scientific terms used herein has usual with the application person of an ordinary skill in the technical field The identical meanings of understanding.
It should be noted that term used herein above is merely to describe specific implementation mode, and be not intended to restricted root According to the illustrative embodiments of the application.As used herein, unless the context clearly indicates otherwise, otherwise singulative It is also intended to include plural form, additionally, it should be understood that, when in the present specification using term "comprising" and/or " packet Include " when, indicate existing characteristics, step, operation, device, component and/or combination thereof.
In the present invention, term for example "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", The orientation or positional relationship of the instructions such as " side ", "bottom" is to be based on the orientation or positional relationship shown in the drawings, only to facilitate chatting The relative for stating each component of the utility model or component structure relationship and determination, not refer in particular in the utility model either component or Element should not be understood as limiting the present invention.
In the utility model, term such as " affixed ", " connected ", " connection " shall be understood in a broad sense, and expression can be fixed Connection, can also be to be integrally connected or be detachably connected;It can be directly connected, the indirect phase of intermediary can also be passed through Even.Related scientific research for this field or technical staff can determine above-mentioned term in the present invention as the case may be Concrete meaning, should not be understood as limiting the present invention.
As background technology is introduced, conventional tri-level half-bridge inversion topological exists in the prior art and mostly uses hard switching On-off mode, switching loss is larger, the problem of limiting the further promotion of switching frequency, in order to which the technology for solving as above is asked Topic, this application provides a kind of tri-level half-bridge Sofe Switch convertor circuit, which can make each switching tube when shutdown is connected It is in Sofe Switch state.
As shown in Figure 1, a kind of tri-level half-bridge Sofe Switch convertor circuit, including input bleeder circuit, tri-level half-bridge are inverse It is inverse to become circuit, transformer T, pulsactor Lx, capacitance Cx and output circuit, the input bleeder circuit and tri-level half-bridge Become circuit in parallel, the tri-level half-bridge inverter circuit includes switching tube bridge arm circuit and switching tube clamp circuit, the switch Pipe clamp circuit midpoint is connected with input bleeder circuit midpoint O, the transformer primary side, pulsactor Lx and capacitance Cx strings Connection, one end is connected with switching tube bridge arm circuit midpoint A after series connection, and the other end is connected with input bleeder circuit midpoint O, institute Transformer T pairs side is stated with output circuit to be connected.
Embodiment one:
The input bleeder circuit includes input capacitance C1 and input capacitance C2, the input capacitance C1 and input capacitance C2 It is connected in series with.
The tri-level half-bridge inverter circuit includes two pole switching tube Q1~Q4 and clamper with anti-paralleled diode Pipe D1 and D2, the switching tube Q1~Q4 are sequentially connected in series, and form switching tube bridge arm circuit, wherein switching tube Q1 and switching tube Q2 groups At bridge arm circuit on switching tube, switching tube Q3 and switching tube Q4 form switching tube lower bridge arm circuit, the clamp diode D1 and D2 is connected in series with, and forms switching tube clamp circuit, switching tube clamp circuit one end (i.e. the cathode of D1) and bridge on switching tube Arm midpoint is connected, and the other end (i.e. the anode of D2) is connected with switching tube lower bridge arm midpoint.
The pulsactor Lx carries out air-gap-free assembly using the magnetic cores such as ferrite, amorphous, and in low current, inductance value is very Greatly, as electric current increases, magnetic core saturation, inductance value becomes very little.
The specific control mode of the tri-level half-bridge Sofe Switch convertor circuit is:Switching tube Q1 and Q4 is complementary conducting, Switching tube Q2 and Q3 is complementary is connected;Switching tube Q1 and Q4 carry out PWM modulation, and Q2 and Q3 are without PWM modulation;Switching tube Q1 and Q2 is in same PWM cycle turn-on and turn-off, wherein Q1 is turned off in advance, Q2 lag shutdowns;Switching tube Q3 and Q4 was at another PWM weeks Phase turn-on and turn-off, wherein Q4 is turned off in advance, Q3 lag shutdowns;Specific on, off sequential such as Fig. 4 of switching tube Q1~Q4 It is shown.The utility model can be realized each switching tube using Q1 and Q4 by the characteristic of input capacitance C1 or C2 voltage clamping The effect of dynamic electric voltage clamper, meanwhile, coordinate pulsactor Lx and capacitance Cx to realize the effect of Sofe Switch.
Embodiment two:
As shown in Fig. 2, the embodiments of the present invention two are the tri-level half-bridge Sofe Switch convertor circuit in embodiment one On the basis of, shunt capacitance is distinguished at each switching tube both ends of tri-level half-bridge inverter circuit bridge arm, for further reducing The turn-off power loss of switching tube.
The circuit other structures and circuit operation principle of the present embodiment are identical as embodiment one, and details are not described herein.
Embodiment three:
As shown in figure 3, the embodiments of the present invention three are the tri-level half-bridge Sofe Switch convertor circuit in embodiment one On the basis of, in the both ends parallel connection striding capacitance Cs1 of switching tube clamp circuit, to realize the one-to-one of upper and lower bridge arm switching tube Pressure is changed, under the premise of using more simple control mode, realizes switching tube dynamic electric voltage clamper, but answering for circuit can be increased Miscellaneous degree.
The circuit other structures and circuit operation principle of the present embodiment are identical as embodiment one, and details are not described herein.
In specific implementation, operating mode of the utility model in half of PWM cycle is as follows:
Operating mode 1
As shown in figure 5, switching tube Q1, Q2 are in the conduction state, current path is O → C1 → Q1 → Q2 → Lx → T → Cx → O, it is assumed that pulsactor has been saturated in this stage, and the influence to circuit can be ignored, and Lo is sufficiently large, can be equivalent to constant-current source And conversion to primary current is Ix, this stage work principle is equivalent to constant-current source and charges to Cx, and the voltage linear on Cx rises.
Operating mode 2
As shown in fig. 6, Q1 is turned off, Q2 is held on, and the junction capacity or shunt capacitance of Q1 is primary side current of transformer Ix's The lower charging of effect, voltage gradually rise, and Q1 realizes zero voltage turn-off, meanwhile, Q3, Q4 both end voltage continuously decrease, when Q1 voltages When being increased to C1 voltages, D1 conductings, circuit enters operating mode 3.
Operating mode 3
As shown in fig. 7, diode D1 is connected with switching tube Q2, current path is O → D1 → Q2 → Lx → T → Cx → O, secondary Side rectifier diode D5, D6 conducting, by transformer short-circuit, circuit equivalent is the LC oscillating circuits being made of Lx, Cx, due to circuit The presence of parasitic inductance and transformer leakage inductance, electric current will not disappear at once in circuit, but under Cx barrier effects, in circuit Electric current is constantly being decayed, and when the small saturation current value to Lx of electric current, Lx participates in work, and Lx is pulsactor, once it exits full It will be increased to, inductance value very big, the electric current in circuit decays to zero substantially at this time.
Operating mode 4
As shown in figure 8, switching tube Q2 shutdowns, diode D1 conductings, when Q2 is turned off, the electric current flowed through in circuit is full for Lx And electric current, electric current very little, Q2 can be equivalent to zero-current switching, Q2 junction capacity charges under the action of Ix, and voltage is gradual It increases, Q3, Q4 both end voltage continuously decrease, and when Q2 is increased to C2 voltages, Q3, Q4 anti-paralleled diode conducting, circuit enter Operating mode 5.
Operating mode 5
As shown in figure 9, Q3, Q4 anti-paralleled diode are connected, loop current will be 0 rapidly under the action of busbar voltage, After certain dead time, Q3, Q4 conducting, due to the presence of pulsactor, loop current very little, Q3, Q4 can be equivalent For zero current turning-on.
The working condition of other half of PWM cycle is symmetrical.
All switching tubes are can be seen that from above switching process, and the effect that Sofe Switch can be realized when shutdown is being connected Fruit.
A kind of tri-level half-bridge Sofe Switch convertor circuit disclosed by the utility model is in welding machine, electrolysis water power supply or charger It can be applied in equal specific products.
The foregoing is merely the preferred embodiments of the application, are not intended to limit this application, for the skill of this field For art personnel, the application can have various modifications and variations.Within the spirit and principles of this application, any made by repair Change, equivalent replacement, improvement etc., should be included within the protection domain of the application.
It is above-mentioned although specific embodiments of the present invention are described with reference to the accompanying drawings, but not to this practicality newly The limitation of type protection domain, those skilled in the art should understand that, based on the technical solution of the present invention, ability Field technique personnel need not make the creative labor the various modifications or changes that can be made still in the protection model of the utility model Within enclosing.

Claims (10)

1. a kind of tri-level half-bridge Sofe Switch convertor circuit, it is characterised in that:Including input bleeder circuit, tri-level half-bridge inversion Circuit, transformer and output circuit, the input bleeder circuit is in parallel with tri-level half-bridge inverter circuit, the tri-level half-bridge Inverter circuit includes switching tube bridge arm circuit and switching tube clamp circuit, and switching tube clamp circuit midpoint and input partial pressure are electric Road midpoint is connected, the transformer primary side, pulsactor and capacitance series connection, one end and the switching tube bridge arm after series connection Circuit midpoint is connected, and the other end is connected with input bleeder circuit midpoint, and the transformer secondary is connected with output circuit.
2. a kind of tri-level half-bridge Sofe Switch convertor circuit as described in claim 1, which is characterized in that the input partial pressure electricity Road includes 2 input capacitances, and the input capacitance is connected in series with.
3. a kind of tri-level half-bridge Sofe Switch convertor circuit as described in claim 1, which is characterized in that the switching tube bridge arm Circuit includes bridge arm circuit and switching tube lower bridge arm circuit on the switching tube being connected in series with, switching tube clamp circuit one end with Bridge arm midpoint is connected on switching tube, and the other end is connected with switching tube lower bridge arm midpoint.
4. a kind of tri-level half-bridge Sofe Switch convertor circuit as claimed in claim 3, which is characterized in that the switching tube bridge arm Circuit includes 4 switching tubes for carrying anti-paralleled diode, and the switching tube is sequentially connected in series, both the above switching tube composition switch Bridge arm on pipe, following two switching tube form switching tube lower bridge arm.
5. a kind of tri-level half-bridge Sofe Switch convertor circuit as claimed in claim 3, which is characterized in that the switching tube clamper Circuit includes 2 clamp diodes, and the clamp diode is connected in series with.
6. a kind of tri-level half-bridge Sofe Switch convertor circuit as claimed in claim 3, which is characterized in that the switching tube bridge arm Circuit includes 4 switching tubes for carrying anti-paralleled diode, and each switching tube both ends are parallel with capacitance respectively, and the switching tube is successively Series connection, both the above switching tube form bridge arm on switching tube, and following two switching tube forms switching tube lower bridge arm.
7. a kind of tri-level half-bridge Sofe Switch convertor circuit as claimed in claim 3, which is characterized in that the switching tube clamper Circuit includes 2 clamp diodes, and the clamp diode is connected in series with, and switching tube clamp circuit both ends have been arranged in parallel Striding capacitance.
8. a kind of welding machine includes a kind of tri-level half-bridge Sofe Switch convertor circuit as described in claim 1-7 is any.
9. a kind of electrolysis water power supply includes a kind of tri-level half-bridge Sofe Switch convertor circuit as described in claim 1-7 is any.
10. a kind of charger includes a kind of tri-level half-bridge Sofe Switch convertor circuit as described in claim 1-7 is any.
CN201820243972.7U 2018-02-09 2018-02-09 Tri-level half-bridge Sofe Switch convertor circuit, welding machine, electrolysis water power supply and charger Active CN207910685U (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109361323A (en) * 2018-11-14 2019-02-19 厦门科华恒盛股份有限公司 I type three-level soft switch circuit and corresponding three-phase translation circuit and converter plant
CN110474550A (en) * 2019-08-21 2019-11-19 阳光电源股份有限公司 A kind of striding capacitance type NPC three-level topology
CN112994499A (en) * 2021-03-02 2021-06-18 济宁奥太电气有限公司 Three-level half-bridge soft switch converter circuit, control system and control method thereof

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109361323A (en) * 2018-11-14 2019-02-19 厦门科华恒盛股份有限公司 I type three-level soft switch circuit and corresponding three-phase translation circuit and converter plant
CN109361323B (en) * 2018-11-14 2020-05-15 科华恒盛股份有限公司 I-type three-level soft switching circuit and corresponding three-phase conversion circuit and converter
CN110474550A (en) * 2019-08-21 2019-11-19 阳光电源股份有限公司 A kind of striding capacitance type NPC three-level topology
CN112994499A (en) * 2021-03-02 2021-06-18 济宁奥太电气有限公司 Three-level half-bridge soft switch converter circuit, control system and control method thereof
CN112994499B (en) * 2021-03-02 2022-03-29 济宁奥太电气有限公司 Three-level half-bridge soft switch converter circuit, control system and control method thereof

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