CN206807294U

CN206807294U - Two-way DC DC converters and charger

Info

Publication number: CN206807294U
Application number: CN201720630918.3U
Authority: CN
Inventors: 曾赣生; 陈小佳
Original assignee: Shenzhen Delihe Energy Technology Co Ltd
Current assignee: Shenzhen Delihe Energy Technology Co Ltd
Priority date: 2017-06-01
Filing date: 2017-06-01
Publication date: 2017-12-26
Anticipated expiration: 2027-06-01

Abstract

The utility model discloses a kind of two-way DC DC converters and charger, the two-way DC DC converters include four road IGBT bridges, the first reactor, the second reactor, the first cathode power supply input/output terminal, the second cathode power supply input/output terminal, the negative electricity source, the first filter circuit, the second filter circuit and control panel, first IGBT bridges and the 2nd IGBT bridges are connected with the first cathode power supply input/output terminal respectively, and the first IGBT bridges are connected with the first reactor；2nd IGBT bridges are connected with the second reactor；First reactor is connected with the 3rd IGBT bridges；Second reactor is connected with the 4th IGBT bridges；3rd IGBT bridges and the 4th IGBT bridges are also connected with the second cathode power supply input/output terminal respectively；Controlled end of the control panel respectively with four road IGBT bridges is connected.The utility model solves in DC DC converters the problem of cost is higher, is unfavorable for transport.

Description

Bidirectional DC-DC converter and charger

Technical Field

The utility model relates to an electronic circuit technical field, in particular to two-way DC-DC converter and machine that charges.

Background

The bidirectional DC/DC converter can convert one kind of DC electric energy into another kind of DC electric energy, and mainly converts voltage and current. The method is widely applied to the fields of renewable energy sources, power systems, traffic, aerospace, computers, communication, household appliances, national defense and military industry, industrial control and the like. The bidirectional DC/DC can realize that the input of large voltage and small current is converted into small voltage and large current through a DC converter or the input of small voltage and large current is converted into large voltage and small current through a converter.

Most of the existing bidirectional DC/DC converters adopt a reactor with a large volume to perform voltage boosting or voltage reduction processing and then output, so as to ensure that large power is output to a power load, and correspondingly, a radiator needs to be adapted to avoid the danger that a direct-current power supply is scalded and burnt due to serious temperature rise. The reactor and the adaptive radiator are heavy in size, high in cost and not beneficial to transportation.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a two-way DC-DC converter and machine that charges aims at solving two-way DC-DC converter, and the radiator volume of reactor and adaptation is heavy, and the cost is higher, is unfavorable for the problem of transportation.

In order to achieve the above object, the present invention provides a bidirectional DC-DC converter, which comprises four IGBT bridges, a first reactor, a second reactor, a first positive power input/output end, a second positive power input/output end, a negative power end, a first filter circuit, a second filter circuit, and a control panel, wherein the first conduction ends of the first IGBT bridge and the second IGBT bridge in the four IGBT bridges are respectively connected to the first positive power input/output end, and the first IGBT bridge is connected to the first end of the first reactor; a second conduction end of the second IGBT bridge circuit is connected with a first end of the second reactor; the second end of the first reactor is connected with the first conducting end of a third IGBT bridge circuit in the four paths of IGBT bridge circuits; the second end of the second reactor is connected with the first conduction end of the fourth IGBT bridge circuit; second conduction ends of the third IGBT bridge circuit and the fourth IGBT bridge circuit are respectively connected with the input/output end of the second positive power supply; the control board is respectively connected with controlled ends of the four paths of IGBT bridge circuits; the first filter circuit is arranged between the first positive power supply input/output end and the negative power supply end in series; the second filter circuit is arranged between the second positive power supply input/output end and the negative power supply end in series; wherein,

and the control board is used for controlling the four paths of IGBT bridge circuits to work according to a control signal input by the upper computer.

Preferably, the first IGBT bridge circuit includes a first IGBT upper bridge arm and a first IGBT lower bridge arm, gate electrodes of the first IGBT upper bridge arm and the first IGBT lower bridge arm are both connected to the control board, a collector of the first IGBT upper bridge arm is a first conducting end of the first IGBT bridge circuit, an emitter of the first IGBT upper bridge arm is connected to a collector of the first IGBT lower bridge arm, and a common end of the emitter of the first IGBT upper bridge arm and the collector of the first IGBT lower bridge arm is a second conducting end of the first IGBT bridge circuit; and the emitting electrode of the first IGBT lower bridge arm is connected with the negative electrode power supply end.

Preferably, the second IGBT bridge circuit includes a second IGBT upper bridge arm and a second IGBT lower bridge arm, gate electrodes of the second IGBT upper bridge arm and the second IGBT lower bridge arm are both connected to the control board, a collector of the second IGBT upper bridge arm is a first conducting end of the second IGBT bridge circuit, an emitter of the second IGBT upper bridge arm is connected to a collector of the second IGBT lower bridge arm, and a common end of the emitter of the second IGBT upper bridge arm and the collector of the second IGBT lower bridge arm is a second conducting end of the second IGBT bridge circuit; and the emitter of the second IGBT lower bridge arm is connected with the cathode power supply end.

Preferably, the third IGBT bridge circuit includes a third IGBT upper bridge arm and a third IGBT lower bridge arm, gate electrodes of the third IGBT upper bridge arm and the third IGBT lower bridge arm are both connected to the control board, a collector of the third IGBT upper bridge arm is a first conducting end of the third IGBT bridge circuit, an emitter of the third IGBT upper bridge arm is connected to a collector of the third IGBT lower bridge arm, and a common end of the emitter of the third IGBT upper bridge arm and the collector of the third IGBT lower bridge arm is a second conducting end of the third IGBT bridge circuit; and the emitter of the third IGBT lower bridge arm is connected with the cathode power supply end.

Preferably, the fourth IGBT bridge circuit includes a fourth IGBT upper bridge arm and a fourth IGBT lower bridge arm, gate electrodes of the fourth IGBT upper bridge arm and the fourth IGBT lower bridge arm are both connected to the control board, a collector of the fourth IGBT upper bridge arm is a first conducting end of the fourth IGBT bridge circuit, an emitter of the fourth IGBT upper bridge arm is connected to a collector of the fourth IGBT lower bridge arm, and a common end of the emitter of the fourth IGBT upper bridge arm and the collector of the fourth IGBT lower bridge arm is a second conducting end of the fourth IGBT bridge circuit; and the emitter of the fourth IGBT lower bridge arm is connected with the cathode power supply end.

Preferably, the first filter circuit of the bidirectional DC-DC converter includes a first resistor and a plurality of first capacitors, a first end of the first resistor is connected to the first positive power input/output end, and a second end of the first resistor is connected to the negative power end; a plurality of first capacitors are arranged in parallel with the first resistors;

the second filter circuit comprises a second resistor and a plurality of second capacitors, wherein a first end of the second resistor is connected with the input/output end of the second positive power supply, and a second end of the second resistor is connected with the negative power supply end; the second capacitors are arranged in parallel with the second resistors.

Preferably, the bidirectional DC-DC converter further includes a pre-charge circuit disposed in series between the first positive power supply input/output terminal and the first IGBT bridge and/or between the second positive power supply input/output terminal and the second IGBT bridge.

Preferably, the pre-charging circuit comprises a circuit breaker, a contactor and a third resistor, wherein the input end of the contactor is interconnected with the first positive power input/output end and the first input end of the circuit breaker, and the output end of the contactor is connected with the first end of the third resistor; the second end of the third resistor is connected with the first output end of the circuit breaker; and the second input end and the second output end of the circuit breaker are connected in series on the negative power supply end.

Preferably, the bidirectional DC-DC converter further includes a common mode magnetic loop, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor, the common mode magnetic loop is disposed around the lines of the first positive power input/output terminal and the negative power terminal;

the third capacitor is arranged between the input/output end of the first positive power supply and the ground in series; the fourth capacitor is arranged between the negative power supply end and the ground in series; the fifth capacitor is arranged between the second positive power supply input/output end and the ground in series; the sixth capacitor is arranged between the negative power supply end and the ground in series.

The utility model also provides a charger, which comprises the bidirectional DC-DC converter; the bidirectional DC-DC converter comprises four paths of IGBT bridges, a first reactor, a second reactor, a first positive power supply input/output end, a second positive power supply input/output end, the negative power supply end, a first filter circuit, a second filter circuit and a control panel, wherein first breakover ends of the first IGBT bridge and the second IGBT bridge in the four paths of IGBT bridges are respectively connected with the first positive power supply input/output end, and the first IGBT bridge is connected with a first end of the first reactor; a second conduction end of the second IGBT bridge circuit is connected with a first end of the second reactor; the second end of the first reactor is connected with the first conducting end of a third IGBT bridge circuit in the four paths of IGBT bridge circuits; the second end of the second reactor is connected with the first conduction end of the fourth IGBT bridge circuit; second conduction ends of the third IGBT bridge circuit and the fourth IGBT bridge circuit are respectively connected with the input/output end of the second positive power supply; the control board is respectively connected with controlled ends of the four paths of IGBT bridge circuits; the first filter circuit is arranged between the first positive power supply input/output end and the negative power supply end in series; the second filter circuit is arranged between the second positive power supply input/output end and the negative power supply end in series; wherein,

The utility model discloses a set up the same IGBT bridge circuit of four ways structure and the reactor that sets up with it and carry out the BOOST/reduce the price with the voltage of first positive power supply input/output end or second positive power supply input/output end input and handle the back output, each four ways IGBT bridge circuit structure is the same, and constitute two sets of parallelly connected BUCK return circuits/BOOST return circuits that set up, make the total electric current that flows through DC-DC converter equal to the sum of the electric current that flows through each BUCK return circuit/BOOST return circuit, so set up, in the DC-DC converter that needs to satisfy high-power output, when guaranteeing that every output voltage is unchangeable, shunt the electric current of DC-DC converter through two BUCK return circuits/BOOST return circuits, in order to reduce the electric current that flows through reactor in each BUCK return circuit/BOOST return circuit, and then the power of reactor, so set up, the phenomenon that the temperature of the DC-DC converter is seriously raised due to overhigh power of the reactor is avoided, and further the work load of the radiator can be reduced. Because two sets of BUCK loops/BOOST loops which are arranged in parallel, the first reactor and the second reactor are also equivalent to be connected in parallel, the parallel reactors can ensure the inductance value, and meanwhile, the flexibility of the layout of the power panel is improved by two small reactors, so that the size of the power panel is effectively reduced, and the size of the bidirectional DC-DC converter is reduced. The utility model provides a two-way DC-DC converter need adopt the big reactor of inductance energy storage to carry out the energy storage in order to guarantee powerful output, and the energy storage of reactor is directly proportional rather than the volume, has restricted the problem of the whole frivolous development of power supply unit DC-DC.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a schematic diagram of functional modules of the bidirectional DC-DC converter of the present invention applied to a charger;

fig. 2 is a schematic circuit diagram of an embodiment of the bidirectional DC-DC converter of fig. 1.

The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that, if directional indications (such as upper, lower, left, right, front and rear … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description relating to "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The utility model provides a two-way DC-DC converter.

Referring to fig. 1, in an embodiment of the present invention, the bidirectional DC-DC converter includes four IGBT bridges, a first reactor L1, a second reactor L2, a first positive power input/output terminal V1+, a second positive power input/output terminal V2+, the negative power source terminal V-, a first filter circuit 10, a second filter circuit 20, and a control board 30.

First conduction ends of a first IGBT bridge circuit S1 and a second IGBT bridge circuit S2 in the four IGBT bridge circuits are respectively connected with the first positive power supply input/output end V1+, and a second conduction end of the first IGBT bridge circuit S1 is connected with a first end of the first reactor L1; a second conduction end of the second IGBT bridge circuit S2 is connected to a first end of the second reactor L2; the second end of the first reactor L1 is connected with the first conducting end of a third IGBT bridge circuit S3 in the four IGBT bridge circuits; the second end of the second reactor is connected with the first conduction end of the fourth IGBT bridge circuit; second conduction ends of the third IGBT bridge circuit S3 and the fourth IGBT bridge circuit S4 are respectively connected with the second positive power supply input/output end V2 +; the control board 30 is respectively connected with controlled ends of the four paths of IGBT bridge circuits; the first filter circuit 10 is serially connected between the first positive power input/output end V1+ and the negative power source end V-; the second filter circuit 20 is serially connected between the second positive power input/output end V2+ and the negative power source end V-; wherein,

and the control board 30 is used for controlling the four paths of IGBT bridge circuits to work according to a control signal input by an upper computer.

In this embodiment, the first filter circuit 10 and the second filter circuit 20 are used to filter out ripples in the input/output voltage. The control board 30 is provided with a DSP chip inside, is in communication connection with the upper computer through a communication interface, and works with four paths of IGBT bridges according to control signals input by the upper computer based on user requirements.

Specifically, in the step-down operation mode, the first positive power input/output terminal V1+ serves as an input terminal of the bidirectional DC-DC converter, the freewheeling diode and the reactor L1 in the upper arm of the first IGBT bridge S1 and the third IGBT bridge S3 constitute a BUCK circuit, the freewheeling diode and the reactor L2 in the upper arm of the second IGBT bridge S2 and the fourth IGBT bridge S4 constitute another BUCK circuit, and the second positive power input/output terminal V2+ serves as an output terminal of the bidirectional DC-DC converter, so that the current is transmitted from the first positive power input/output terminal V1+ to the second positive power input/output terminal V2+ in a step-down manner. Or the second positive power input/output end V2+ is used as the input end of the bidirectional DC-DC converter, the freewheeling diode in the upper arm of the third IGBT bridge S3, the first IGBT bridge S1 and the reactor L1 form a BUCK circuit, the freewheeling diode in the upper arm of the fourth IGBT bridge S4, the second IGBT bridge S2 and the reactor L2 form another BUCK circuit, and the first positive power input/output end V1+ is used as the output end of the bidirectional DC-DC converter; thereby realizing the step-down transmission of current from the second positive power supply input/output end V2+ to the first positive power supply input/output end V1 +.

In a BOOST working mode, the first positive power input/output end V1+ is used as an input end of the bidirectional DC-DC converter, the upper arm of the first IGBT bridge S1 is always conductive, the third IGBT bridge S3 and the reactor L1 constitute a BOOST circuit, the upper arm of the second IGBT bridge S1 is always conductive, the fourth IGBT bridge S4 and the reactor L2 constitute another BOOST circuit, and the second positive power input/output end V2+ is used as an output end of the bidirectional DC-DC converter, so that the current is boosted and transmitted from the first positive power input/output end V1+ to the second positive power input/output end V2 +. Or, the second positive power input/output end V2+ the input end of the bidirectional DC-DC converter, the upper arm of the third IGBT bridge S3 is always conducted, the first IGBT bridge S1 and the reactor L1 constitute a BOOST circuit, the upper arm of the fourth IGBT bridge S4 is always conducted, the second IGBT bridge S2 and the reactor L2 constitute another BOOST circuit, and the first positive power input/output terminal V1+ serves as the output terminal of the bidirectional DC-DC converter, thereby realizing the boosting transmission of current from the second positive power supply input/output terminal V2+ to the first positive power supply input/output terminal V1+, according to the arrangement, the input and output symmetrical topological structure realizes the bidirectional flow of energy in any voltage range, and compared with a single BUCK circuit and a single BOOST circuit, the bidirectional DC-DC converter is small in size and low in cost. Furthermore, the utility model discloses a BUCK, the BOOST circuit of sharing reactor L1, the design of L2 have realized that output voltage full range is adjustable.

In a preferred embodiment, the first IGBT bridge S1 includes a first IGBT upper leg S1H and a first IGBT lower leg S1L, a gate of the first IGBT upper leg S1H and a gate of the first IGBT lower leg S1L are both connected to the control board 30, a collector of the first IGBT upper leg S1H is a first conducting end of the first IGBT bridge S1, an emitter of the first IGBT upper leg S1H is connected to a collector of the first IGBT lower leg S1L, and a common end of the emitter of the first IGBT upper leg S1H and the collector of the first IGBT lower leg S1L is a second conducting end of the first IGBT bridge S1; and the emitter of the first IGBT lower bridge arm S1L is connected with the negative electrode power supply end V-.

In this embodiment, the first IGBT upper arm S1H and the first IGBT lower arm S1L are provided with antiparallel diodes, and are arranged in this way. The first IGBT upper bridge arm S1H and the first IGBT lower bridge arm S1L can realize the switching function and have the function of a freewheeling diode, so that the size of the DC-DC converter circuit board is further reduced, and the cost is reduced.

In a preferred embodiment, the second IGBT bridge S2 includes a second IGBT upper leg S2H and a second IGBT lower leg S2L, a gate of the second IGBT upper leg S2H and a gate of the second IGBT lower leg S2L are both connected to the control board 30, a collector of the second IGBT upper leg S2H is a first conducting end of the second IGBT bridge S2, an emitter of the second IGBT upper leg S2H is connected to a collector of the second IGBT lower leg S2L, and a common end of the emitter of the second IGBT upper leg S2H and the collector of the second IGBT lower leg S2L is a second conducting end of the second IGBT bridge S2; and the emitter of the second IGBT lower bridge arm S2L is connected with the negative electrode power supply end V-.

In this embodiment, the second IGBT upper arm S2H and the second IGBT lower arm S2L are provided with antiparallel diodes, and are arranged in this way. The second IGBT upper bridge arm S2H and the second IGBT lower bridge arm S2L can realize the switching function and have the function of a freewheeling diode, so that the size of the DC-DC converter circuit board is further reduced, and the cost is reduced.

In a preferred embodiment, the third IGBT bridge S3 includes a third IGBT upper arm S3H and a third IGBT lower arm S3L, gates of the third IGBT upper arm S3H and the third IGBT lower arm S3L are both connected to the control board 30, a collector of the third IGBT upper arm S3H is a first conducting end of the third IGBT bridge S3, an emitter of the third IGBT upper arm S3H is connected to a collector of the third IGBT lower arm S3L, and a common end of the emitter of the third IGBT upper arm S3H and the collector of the third IGBT lower arm S3L is a second conducting end of the third IGBT bridge S3; and the emitter of the third IGBT lower bridge arm S3L is connected with the negative electrode power supply end V-.

In this embodiment, the third IGBT upper arm S3H and the third IGBT lower arm S3L are provided with antiparallel diodes, and are arranged in this way. The third IGBT upper bridge arm S3H and the third IGBT lower bridge arm S3L can realize the switching function and have the function of a freewheeling diode, so that the size of the DC-DC converter circuit board is further reduced, and the cost is reduced.

In a preferred embodiment, the fourth IGBT bridge S4 includes a fourth IGBT upper leg S4H and a fourth IGBT lower leg S4L, gates of the fourth IGBT upper leg S4H and the fourth IGBT lower leg S4L are both connected to the control board 30, a collector of the fourth IGBT upper leg S4H is a first conducting end of the second IGBT bridge, an emitter of the fourth IGBT upper leg S4H is connected to a collector of the fourth IGBT lower leg S4L, and a common end of the emitter of the fourth IGBT upper leg S4H and the collector of the fourth IGBT lower leg S4L is a second conducting end of the fourth IGBT bridge S4; and the emitter of the fourth IGBT lower bridge arm S4L is connected with the negative electrode power supply end V-.

In this embodiment, the fourth IGBT upper leg S4H and the fourth IGBT leg S4L are provided with antiparallel diodes, and are arranged in this way. The fourth IGBT upper bridge arm S4H and the fourth IGBT lower bridge arm S4L can realize the switching function and have the function of a freewheeling diode, so that the size of the DC-DC converter circuit board is further reduced, and the cost is reduced.

In a preferred embodiment, the first filter circuit 10 includes a first resistor R1 and a plurality of first capacitors C1, a first end of the first resistor R1 is connected to the first positive power input/output terminal V1+, and a second end of the first resistor R1 is connected to the negative power terminal V —; the first capacitors C1 are connected in parallel with the first resistor R1.

In this embodiment, a plurality of first capacitors C1 that are arranged in parallel are used for filtering the ripple in the first positive power supply input/output end V1+ input power supply, and a plurality of first capacitors are connected in parallel, can charge or discharge simultaneously, have increased instantaneous discharge power, have reduced charge time. The first resistor R1 is a bleeder resistor for discharging the electric energy stored in the plurality of first capacitors C1 when the bidirectional DC-DC converter stops working.

In a preferred embodiment, the second filter circuit 20 includes a second resistor R2 and a plurality of second capacitors C2, a first end of the second resistor R2 is connected to the second positive power input/output terminal V2+, and a second end of the second resistor R2 is connected to the negative power terminal V —; the second capacitors C2 are connected in parallel with the second resistor R2.

In this embodiment, a plurality of second electric capacity C2 that set up in parallel are used for filtering the ripple among the second positive power supply input/output end V2+ input power supply, and a plurality of second holds parallelly connected each other, can charge or discharge simultaneously, has increased instantaneous discharge power, has reduced charge time. The second resistor R2 is a bleeder resistor for discharging the electric energy stored in the plurality of second capacitors C2 when the bidirectional DC-DC converter stops working.

In a preferred embodiment, the bidirectional DC-DC converter further comprises a pre-charge circuit 40, the pre-charge circuit 40 being arranged in series between the first positive power supply input/output terminal V1+ and the first IGBT bridge S1 and/or between the second positive power supply input/output terminal V2+ and the second IGBT bridge S2.

In this embodiment, it can be understood that, the DC-DC converter of the present invention is an input and output symmetrical topology, and the pre-charging circuit 40 can be disposed between the first positive power input/output terminal V1+ and the first IGBT bridge S1, between the second positive power input/output terminal V2+ and the second IGBT bridge S2, or between the first positive power input/output terminal V1+ and the first IGBT bridge S1 and between the second positive power input/output terminal V2+ and the second IGBT bridge S2. The present embodiment is described by taking an example in which the precharge circuit 40 is disposed between the first positive power input/output terminal V1+ and the first IGBT bridge S1. When the bidirectional DC-DC converter outputs electric power from the first positive power supply input/output terminal V1+ to the second positive power supply input/output terminal V2+, the current output to the first IGBT bridge S1 is slowly increased by the precharge circuit 40, reducing the impact of the large-current first IGBT bridge S1.

Further, in the above embodiment, the pre-charging circuit includes a breaker QF1, a contactor KM1 and a third resistor R3, an input terminal of the contactor KM1 is interconnected with the first positive power input/output terminal V1+ and the first input terminal of the breaker QF1, and an output terminal of the contactor KM1 is connected with the first terminal of the third resistor R3; a second end of the third resistor R3 is connected with a first output end of the breaker QF 1; and a second input end and a second output end of the breaker QF1 are connected in series on the negative power supply end V-.

In this embodiment, the third resistor R3 is a voltage-resistant high-power resistor, and when the bidirectional DC-DC converter outputs electric energy from the first positive power supply input/output terminal V1+ to the second positive power supply input/output terminal V2+, the contactor KM1 is closed, the breaker QF1 is opened, and the current slowly rises and is output under the action of the third resistor R3, thereby playing a role in protection. When the bidirectional DC-DC converter finishes the pre-charging, the contactor KM1 in the pre-charging circuit 40 is opened; the breaker QF1 is on. When the current in the loop is rapidly increased due to abnormal conditions such as short circuit and the like in the bidirectional DC-DC converter, the circuit breaker QF1 is automatically disconnected, so that the bidirectional DC-DC converter is prevented from being burnt due to overlarge current.

In a preferred embodiment, the bidirectional DC-DC converter further includes a common mode magnetic loop L3, and the common mode magnetic loop L3 is looped on the line of the first positive power input/output terminal V1+ and the negative power terminal V-.

In this embodiment, a common mode choke coil is formed by passing the lines of the first positive power input/output terminal V1+ and the negative power source terminal V-through a common mode magnetic loop L3, so as to suppress the effect of common mode noise.

In a preferred embodiment, the bidirectional DC-DC converter further includes a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5 and a sixth capacitor C6, the third capacitor C3 is disposed in series between the first positive power input/output terminal V1+ and ground; the fourth capacitor C4 is arranged between the negative power supply end V-and the ground in series; the fifth capacitor C5 is serially connected between the second positive power input/output end V2+ and the ground; the sixth capacitor C6 is arranged between the negative power supply terminal V-and the ground in series.

In this embodiment, the capacitors C3, C4, C5, and C6 are safety capacitors for filtering noise in the input power.

The utility model also provides a machine charges, the machine charges includes as above two-way DC-DC converter. The detailed structure of the bidirectional DC-DC converter can refer to the above embodiments, and is not described herein; it can be understood that, because the utility model discloses the machine that charges has used above-mentioned two-way DC-DC converter, consequently, the utility model discloses the embodiment that charges includes all technical scheme of the whole embodiments of above-mentioned two-way DC-DC converter, and the technological effect that reaches is also identical, no longer gives details here.

The above only be the preferred embodiment of the utility model discloses a not consequently restriction the utility model discloses a patent range, all are in the utility model discloses a conceive, utilize the equivalent structure transform of what the content was done in the description and the attached drawing, or direct/indirect application all is included in other relevant technical field the utility model discloses a patent protection within range.

Claims

1. A bidirectional DC-DC converter is characterized by comprising four paths of IGBT bridges, a first reactor, a second reactor, a first positive power input/output end, a second positive power input/output end, a negative power supply end, a first filter circuit, a second filter circuit and a control panel, wherein first conduction ends of the first IGBT bridge and the second IGBT bridge in the four paths of IGBT bridges are respectively connected with the first positive power input/output end, and a second conduction end of the first IGBT bridge is connected with a first end of the first reactor; a second conduction end of the second IGBT bridge circuit is connected with a first end of the second reactor; the second end of the first reactor is connected with the first conducting end of a third IGBT bridge circuit in the four paths of IGBT bridge circuits; the second end of the second reactor is connected with the first conduction end of the fourth IGBT bridge circuit; second conduction ends of the third IGBT bridge circuit and the fourth IGBT bridge circuit are respectively connected with the input/output end of the second positive power supply; the control board is respectively connected with controlled ends of the four paths of IGBT bridge circuits; the first filter circuit is arranged between the first positive power supply input/output end and the negative power supply end in series; the second filter circuit is arranged between the second positive power supply input/output end and the negative power supply end in series; wherein,

2. The bi-directional DC-DC converter of claim 1 wherein the first IGBT bridge comprises a first IGBT upper leg and a first IGBT lower leg, the gates of the first IGBT upper leg and the first IGBT lower leg are both connected to the control board, the collector of the first IGBT upper leg is a first conducting end of the first IGBT bridge, the emitter of the first IGBT upper leg is connected to the collector of the first IGBT lower leg, and the common end of the emitter of the first IGBT upper leg and the collector of the first IGBT lower leg is a second conducting end of the first IGBT bridge; and the emitting electrode of the first IGBT lower bridge arm is connected with the negative electrode power supply end.

3. The bi-directional DC-DC converter of claim 1 wherein the second IGBT bridge comprises a second IGBT upper leg and a second IGBT lower leg, the gates of the second IGBT upper leg and the second IGBT lower leg are both connected to the control board, the collector of the second IGBT upper leg is a first conducting end of the second IGBT bridge, the emitter of the second IGBT upper leg is connected to the collector of the second IGBT lower leg, and the common end of the emitter of the second IGBT upper leg and the collector of the second IGBT lower leg is the second conducting end of the second IGBT bridge; and the emitter of the second IGBT lower bridge arm is connected with the cathode power supply end.

4. The bi-directional DC-DC converter of claim 1 wherein the third IGBT bridge comprises a third IGBT upper leg and a third IGBT lower leg, the gate electrodes of the third IGBT upper leg and the third IGBT lower leg are both connected to the control board, the collector of the third IGBT upper leg is a first conducting end of the third IGBT bridge, the emitter of the third IGBT upper leg is connected to the collector of the third IGBT lower leg, and the common end of the emitter of the third IGBT upper leg and the collector of the third IGBT lower leg is a second conducting end of the third IGBT bridge; and the emitter of the third IGBT lower bridge arm is connected with the cathode power supply end.

5. The bi-directional DC-DC converter of claim 1 wherein the fourth IGBT bridge comprises a fourth IGBT upper leg and a fourth IGBT lower leg, the gates of the fourth IGBT upper leg and the fourth IGBT lower leg are both connected to the control board, the collector of the fourth IGBT upper leg is a first conducting end of the fourth IGBT bridge, the emitter of the fourth IGBT upper leg is connected to the collector of the fourth IGBT lower leg, and the common end of the emitter of the fourth IGBT upper leg and the collector of the fourth IGBT lower leg is a second conducting end of the fourth IGBT bridge; and the emitter of the fourth IGBT lower bridge arm is connected with the cathode power supply end.

6. The bidirectional DC-DC converter of claim 1, wherein the first filter circuit comprises a first resistor and a plurality of first capacitors, a first terminal of the first resistor being connected to the first positive power input/output terminal, a second terminal of the first resistor being connected to the negative power source terminal; a plurality of first capacitors are arranged in parallel with the first resistors;

7. The bidirectional DC-DC converter of claim 1, further comprising a pre-charge circuit disposed in series between the first positive power supply input/output terminal and the first IGBT bridge and/or between the second positive power supply input/output terminal and the second IGBT bridge.

8. The bidirectional DC-DC converter of claim 7, wherein the pre-charge circuit includes a circuit breaker, a contactor, and a third resistor, an input of the contactor being interconnected with the first positive power input/output terminal and the first input of the circuit breaker, an output of the contactor being connected with a first terminal of the third resistor; the second end of the third resistor is connected with the first output end of the circuit breaker; and the second input end and the second output end of the circuit breaker are connected in series on the negative power supply end.

9. The bidirectional DC-DC converter of claim 1, further comprising a common mode magnetic loop, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor, wherein the common mode magnetic loop is disposed around the first positive power input/output terminal and the negative power terminal;

10. A charger characterized in that it comprises a bidirectional DC-DC converter according to any one of claims 1 to 9.