CN208754260U - Electronic DC switch - Google Patents
Electronic DC switch Download PDFInfo
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- CN208754260U CN208754260U CN201821369039.0U CN201821369039U CN208754260U CN 208754260 U CN208754260 U CN 208754260U CN 201821369039 U CN201821369039 U CN 201821369039U CN 208754260 U CN208754260 U CN 208754260U
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Abstract
The utility model discloses a kind of electronic DC switch, and electronic DC switch includes: electrode input end, negative input, cathode output end, cathode output end, signal receiving end, and cathode output end is connect with negative input；The collector of first IGBT switch, the first IGBT switch is connect with electrode input end, and the emitter of the first IGBT switch is connect with cathode output end；First IGBT drive circuit, the input terminal of first IGBT drive circuit is connect with signal receiving end, the output end of first IGBT drive circuit is connect with the IGBT base stage switched, first IGBT drive circuit is opened or is disconnected for controlling the first IGBT switch according to the received control signal of signal receiving end；Absorbing circuit, absorbing circuit are parallel to the input terminal and output end of the first IGBT switch；Freewheeling circuit, freewheeling circuit are connected to the output end and cathode output end of the first IGBT switch.The utility model improves the electrical endurance of electronic DC switch under high voltage, high current.
Description
Technical field
The utility model relates to direct current field of switches, in particular to a kind of electronic DC switch.
Background technique
The dc switch in direct current electrical domain is applied at present, is generally divided into DC relay, D.C. contactor, DC load
Switch or dc circuit breaker.For the above dc switch in high voltage, current state incision deenergizing, electrical endurance is very
It is short, or even only several hundred times.
Utility model content
The main purpose of the utility model is to propose a kind of electronic DC switch, it is intended to improve electronic DC switch in high electricity
Electrical endurance in the state of pressure, high current.
To achieve the above object, the utility model proposes a kind of electronic DC switches, which is characterized in that the DC electronic
Switch includes:
Electrode input end, negative input, cathode output end, cathode output end, signal receiving end, the cathode output end
It is connect with the negative input；The signal receiving end is for receiving control signal；
The collector of first IGBT switch, the first IGBT switch is connect with the electrode input end, and described first
The emitter of IGBT switch is connect with the cathode output end；
The input terminal of first IGBT drive circuit, first IGBT drive circuit is connect with the signal receiving end, institute
The output end for stating the first IGBT drive circuit is connect with the IGBT base stage switched, the first IGBT drive circuit, is used for basis
The received control signal of signal receiving end controls the first IGBT switch and opens or disconnect；
Absorbing circuit, the absorbing circuit are parallel to the input terminal and output end of the first IGBT switch, the absorption
Circuit turns on and off the voltage that the moment is born for absorbing the first IGBT；
Freewheeling circuit, the freewheeling circuit are connected to the output end and the cathode output end of the first IGBT switch,
The freewheeling circuit is used to provide for the induced electromotive force that the load accessed on the cathode output end and cathode output end generates
It releases access.
Optionally, the absorbing circuit is RC absorbing circuit or RCD absorbing circuit.
Optionally, the RC absorbing circuit includes first resistor and first capacitor, the input terminal of the first resistor and institute
Electrode input end connection is stated, the output end of the first resistor and the input terminal of first capacitor are connected in series, the first capacitor
Output end connect with the cathode output end.
Optionally, the freewheeling circuit includes switch driving circuit and switching tube, the switching tube have the first connecting pin,
Second connection end and controlled end, first connecting pin are connect with the IGBT output end switched, the second connection end with
The cathode output end connection, the input terminal of the switch driving circuit are connect with the signal receiving end, the switch driving
The output end of circuit is connect with the controlled end of the switching tube；
The switch driving circuit, for according to the received control signal of the signal receiving end, control switch pipe to be opened
It opens or disconnects.
Optionally, the switching tube is the 2nd IGBT switch, the collector and described first of the 2nd IGBT switch
The emitter series connection of IGBT switch；The base stage of the 2nd IGBT switch is connect with the output end of the switch driving circuit, institute
The emitter for stating the 2nd IGBT switch is connect with the cathode output end；
Alternatively, the switching tube is metal-oxide-semiconductor, the source electrode of the metal-oxide-semiconductor is connect with the first IGBT emitter switched；
The metal-oxide-semiconductor drain electrode is connect with the cathode output end.
Optionally, the freewheeling circuit is diode, the transmitting of the anode of the diode and the first IGBT switch
Pole connection, the cathode of the diode are connect with the cathode output end.
Optionally, the electronic DC switch further includes master switch, the master switch be connected to the electrode input end with
Between the collector of the first IGBT switch.
Optionally, the electronic DC switch further includes being attached on the first IGBT switch, and for described the
First radiator of one IGBT switch heat dissipation；The electronic DC switch further includes being attached in the first resistor, and be used for
The second radiator to radiate to the first resistor.
Optionally, thermistor temperature-sensitive original part is also connected on the radiator.
Optionally, the electronic DC switch further include: voltage sensor, the voltage sensor are parallel to the direct current
The input terminal and output end of electronic switch, the voltage sensor are also connect with the control terminal；Current sensor, the electric current
Sensor series connect the output end and cathode output end of the first IGBT switch, the current sensor also with the control
End connection processed.
In technical solutions of the utility model, by changing common dc switch, it is substituted for and is opened by the IGBT of drive control
It closes, using IGBT switching characteristic, satisfaction works normally under high voltage, high current.It is on the one hand equipped with simultaneously with IGBT switch simultaneously
The absorbing circuit of connection, absorbs IGBT and turns on and off the voltage that the moment is born, and is on the other hand equipped with concatenated with IGBT switch
Freewheeling circuit, the induced electromotive force for loading generation provide access of releasing, and the circuit for passing through freewheeling circuit and load composition is done work
It consumes, to guarantee under the environment such as high pressure, IGBT switch will not cause over-voltage because of unexpected disconnection and damage, to improve
The electrical endurance of IGBT.
Detailed description of the invention
In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only
It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor
Under, the structure that can also be shown according to these attached drawings obtains other attached drawings.
Fig. 1 is the circuit diagram of the utility model room electronic DC switch.
Drawing reference numeral explanation:
| Electrical number | Title | Electrical number | Title |
| Vs | Power supply | ST | First IGBT switch |
| Rd | Resistance | Cd | Capacitor |
| SL | Switching tube | RL | Load |
| V | Voltage sensor | A | Current sensor |
| SW | Master switch |
The embodiments will be further described with reference to the accompanying drawings for the realization, functional characteristics and advantage of the utility model aim.
Specific embodiment
The following will be combined with the drawings in the embodiments of the present invention, carries out the technical scheme in the embodiment of the utility model
Clearly and completely describing, it is clear that described embodiment is only a part of the embodiment of the utility model, rather than all
Embodiment.Based on the embodiments of the present invention, those of ordinary skill in the art are not making creative work premise
Under every other embodiment obtained, fall within the protection scope of the utility model.
It is to be appreciated that if related in the utility model embodiment directionality instruction (such as upper and lower, left and right, it is preceding,
Afterwards ...), then directionality instruction is only used for explaining opposite between each component under a certain particular pose (as shown in the picture)
Positional relationship, motion conditions etc., if the particular pose changes, directionality instruction is also correspondingly changed correspondingly.
In addition, if relating to the description of " first ", " second " etc. in the utility model embodiment, " first ", " the
Two " etc. description is used for description purposes only, and is not understood to indicate or imply its relative importance or is implicitly indicated meaning
The quantity of the technical characteristic shown." first " is defined as a result, the feature of " second " can explicitly or implicitly include at least one
A this feature.It in addition, the technical solution between each embodiment can be combined with each other, but must be with ordinary skill
Based on personnel can be realized, this technical side will be understood that when the combination of technical solution appearance is conflicting or cannot achieve
The combination of case is not present, also not within the protection scope of the requires of the utility model.
The utility model proposes a kind of electronic DC switches, referring to Fig.1, in an embodiment of the utility model, described straight
Galvanic electricity sub switch includes:
The electronic DC switch includes:
Electrode input end, negative input, cathode output end, cathode output end, signal receiving end, the cathode output end
It is connect with the negative input；The signal receiving end is for receiving control signal；
The collector of first IGBT switch, the first IGBT switch is connect with the electrode input end, and described first
The emitter of IGBT switch is connect with the cathode output end；
The input terminal of first IGBT drive circuit, first IGBT drive circuit is connect with the signal receiving end, institute
The output end for stating the first IGBT drive circuit is connect with the IGBT base stage switched, the first IGBT drive circuit, is used for basis
The received control signal of signal receiving end controls the first IGBT switch and opens or disconnect；
Absorbing circuit, the absorbing circuit are parallel to the input terminal and output end of the first IGBT switch, the absorption
Circuit turns on and off the voltage that the moment is born for absorbing the first IGBT；
Freewheeling circuit, the freewheeling circuit are connected to the output end and the cathode output end of the first IGBT switch,
The freewheeling circuit is used to provide for the induced electromotive force that the load accessed on the cathode output end and cathode output end generates
It releases access.
The electronic DC switch, can not be in height by switching off original common DC relay, D.C. contactor etc.
The electronic switch for stablizing, fast implementing circuit disconnection under voltage or high current state, is changed to the IGBT electronic cutting by drive control
It closes, guarantees the stability in the service life of the fast cut-off circuit and electronic switch of circuit under high voltage or high current state.Meanwhile
One in parallel absorbs the first IGBR electricity by absorbing circuit that resistance RD and capacitor CD are composed in series on IGBR electronic switch
The voltage that sub switch ST is opened or born when turning off.Simultaneously in the output end and the cathode output end of the first IGBT switch
The induction electric of generation is loaded when the first IGBT switchs the quick disconnecting circuit under the states such as high voltage equipped with freewheeling circuit
Gesture provides access of releasing, so that protection the first IGBT switch will not be damaged because of over-voltage, thus guarantee its electrical service life,
So that its electrical endurance can be significantly improved compared with ordinary electronic switch.
In the present embodiment, the absorbing circuit is RC absorbing circuit or RCD absorbing circuit, selects RC absorbing circuit here
It is illustrated as the present embodiment, wherein the RC absorbing circuit includes first resistor and first capacitor, the first resistor
Input terminal is connect with the electrode input end, and the output end of the first resistor and the input terminal of first capacitor are connected in series, institute
The output end for stating first capacitor is connect with the cathode output end.The value of Rd, Cd cope with various target electricity by simulation calculation
Operating condition is flowed, the other high-power alloy sheet resistance of ohm level can be selected in the resistance Rd, and it is other that microfarad range can be selected in the capacitor Cd
Thin-film capacitor.
Because RC absorbing circuit or RCD absorbing circuit are far from the technology for being known to the skilled person common sense, here
Just no longer it is further elaborated.
In the present embodiment, the freewheeling circuit includes switch driving circuit and switching tube, and the switching tube has first to connect
End, second connection end and controlled end are connect, first connecting pin is connect with the IGBT output end switched, second connection
End is connect with the cathode output end, and the input terminal of the switch driving circuit is connect with the signal receiving end, the switch
The output end of driving circuit is connect with the controlled end of the switching tube；The switch driving circuit, for being connect according to the signal
The received control signal of receiving end, the unlatching or disconnection of control switch pipe.Freewheeling circuit is for being connected in parallel on load both ends, when flowing through
When current vanishes in load, the induced electromotive force offer for loading generation is released access, clump and protect other originals in circuit
The safety of part.
In the present embodiment, switching tube is the 2nd IGBT switch, the collector and described first of the 2nd IGBT switch
The emitter series connection of IGBT switch；The base stage of the 2nd IGBT switch is connect with the output end of the switch driving circuit, institute
The emitter for stating the 2nd IGBT switch is connect with the cathode output end；
Alternatively, the switching tube is metal-oxide-semiconductor, the source electrode of the metal-oxide-semiconductor is connect with the first IGBT emitter switched；
The metal-oxide-semiconductor drain electrode is connect with the cathode output end.For the stability for guaranteeing freewheeling circuit, switching tube can be selected by driving
Closure/disconnection IGBT switch or metal-oxide-semiconductor are controlled, it is of course also possible to which entire freewheeling circuit can from the aspect of save the cost
Directly to use diode in place, the anode of the diode is connect with the first IGBT emitter switched, the diode
Cathode connect with the cathode output end.Start using diode unilateral conduction, without driving and reaches the advantages that at low cost
The purpose of save the cost.
In the present embodiment, each element often works under high voltage or high current state, since element is there are internal resistance,
Such words element can generate a large amount of heat, and to avoid element from damaging because of high temperature, the galvanic electricity sub switch further includes patch
On the first IGBT switch, and for the first radiator to the first IGBT switch heat dissipation；The DC electronic
Switch further includes the second radiator for being attached in the first resistor, and being used to radiate to the first resistor, the same, it opens
Close the radiator equally posted on pipe for radiating to switching tube.Heat dissipation implement body can be some refrigerating plants or air blast dress
It sets, is also possible to design some holes for ventilation on element watchcase, convenient for flowing to reach nature drop with outside air
The effect of temperature.At the same time it can also use thermistor class temperature-sensitive original part to test radiator actual temp, or member also can be used
NTC resistance built in part realizes monitoring temperature, so as to more intuitive detecting element actual temperature, plays more effectively prevention member
The risk that part is burned.
In the present embodiment, driving DR be equipped with connect with signal control terminal move back be saturated protective device, soft switching device with
And active clamp device.When first switch IGBT is under closed state, drives and move back saturation protective device, soft switching on DR
Device and active clamp device, which can also detect the working environment of first switch IGBT and control first switch IGBT, to exist
Energy reliable turn-off, prevents the first IGBT switch ST from damaging since voltage is excessive or electric current is excessive under extreme working condition.
In the present embodiment, master switch SW can also be connected between entire electronic DC switch and positive pole, it is described
Master switch SW is connected between the electrode input end and the collector of the first IGBT switch.The master switch SW can be straight
Connect and be connected between electrode input end and electronic DC switch input terminal, can also with the one end master switch SW connection positive pole with
Between electronic DC switch input terminal, the other end is connected between power cathode and electronic DC switch output end.Ought always it open
After closing SW disconnection, entire electronic DC switch will be disengaged from charging, and master switch SW is generally used for whole electronic DC switch maintenance, dimension
Use when repairing switches being electrically connected between electronic DC switch and positive pole completely, safe work is provided for maintenance personnel
Environment avoids Danger Electric shock risk.Wherein, master switch SW can select the chopper switch in relatively common disconnecting switch, every
Electricity is convenient, reliable, can also select breaker or switch with knifeshaped fuse.
In the present embodiment, the electronic DC switch further include:
Voltage sensor, the voltage sensor is parallel to the input terminal and output end of the electronic DC switch, described
Voltage sensor is also connect with the control terminal；
Output end and the cathode output of the first IGBT switch is connected in series in current sensor, the current sensor
End, the current sensor are also connect with the control terminal.Electronic DC switch matches voltage sensor circuit, current sensor
Circuit can provide a user the movement floor data of switch, and can be stored in open the action data of switch by corresponding circuit
It closes in control panel memory space, facilitates user's subsequent query or do accident analysis, while can voltage, current signal by acquisition
Additional switch protection function is done, when collected voltage or circuit signal exception, it is disconnected that control terminal will control driving
The first IGBT switch ST disconnection is opened, electronic DC switch is avoided to be in abnormal operation and damage.
In another embodiment, for the application is explained further, the freewheeling circuit is illustrated for selecting IGBT switch.
Firstly, selecting suitable resistance and capacitor by simulation calculation according to the voltage of real work, electric current environment, normally opening
Before dynamic, driving the first IGBT switch ST of starting, due to IGBT switching characteristic, entire circuit transient switching are controlled by control terminal.By
It is connected in parallel to absorbing circuit in the first IGBT switch ST, when circuit just starts or disconnects, absorbing circuit can care for absorption and hold
By the voltage of IGBT, hidden danger is damaged so as to avoid IGBT over-voltage, while entire electronic DC switch is additionally provided with afterflow electricity
Road, states freewheeling circuit for being connected in parallel on load both ends, when flowing through the current vanishes in load, control unit control driving closure the
Two IGBT switch, freewheeling circuit conducting.The induced electromotive force offer that load generates is released access, clump and protect in circuit
The safety of IGBT switch.Simultaneously on the one hand on each component of electronic DC switch be equipped with radiator, prevent each component because
It is burnt out for high temperature, another side, entire electronic DC switch is equipped with voltage, current detection circuit, in real time to electronic DC switch
Working environment detected, and the action data of switch is stored in switch control plate memory space, after facilitating user
Accident analysis is done in continuous inquiry, while when finding voltage or current anomaly, will be controlled driving by control terminal immediately and be disconnected the
One IGBT switch, thus each component of further protection.It is finally equipped with also between electronic DC switch and positive pole total
Switch provides the environment of safety to the maintenance of entire electronic DC switch.
The above is only the preferred embodiment of the present invention, and therefore it does not limit the scope of the patent of the utility model,
Under all utility models in the utility model are conceived, equivalent structure made based on the specification and figures of the utility model
Transformation, or directly/be used in other related technical areas indirectly and be included in the scope of patent protection of the utility model.
Claims (10)
1. a kind of electronic DC switch, which is characterized in that the electronic DC switch includes:
Electrode input end, negative input, cathode output end, cathode output end, signal receiving end, the cathode output end and institute
State negative input connection；The signal receiving end is for receiving control signal；
The collector of first IGBT switch, the first IGBT switch is connect with the electrode input end, and the first IGBT is opened
The emitter of pass is connect with the cathode output end；
The input terminal of first IGBT drive circuit, first IGBT drive circuit is connect with the signal receiving end, and described
The output end of one IGBT drive circuit is connect with the IGBT base stage switched, the first IGBT drive circuit, for according to
The received control signal of signal receiving end controls the first IGBT switch and opens or disconnect；
Absorbing circuit, the absorbing circuit are parallel to the input terminal and output end of the first IGBT switch, the absorbing circuit
The voltage that the moment is born is turned on and off for absorbing the first IGBT；
Freewheeling circuit, the freewheeling circuit is connected to the output end and the cathode output end of the first IGBT switch, described
Freewheeling circuit is used to provide for the induced electromotive force that the load accessed on the cathode output end and cathode output end generates and release
Access.
2. electronic DC switch as described in claim 1, which is characterized in that the absorbing circuit be RC absorbing circuit or
RCD absorbing circuit.
3. electronic DC switch as claimed in claim 2, which is characterized in that the RC absorbing circuit includes first resistor and
One capacitor, the input terminal of the first resistor are connect with the electrode input end, the output end of the first resistor and the first electricity
The input terminal of appearance is connected in series, and the output end of the first capacitor is connect with the cathode output end.
4. electronic DC switch as described in claim 1, which is characterized in that the freewheeling circuit include switch driving circuit and
Switching tube, the switching tube have the first connecting pin, second connection end and controlled end, and first connecting pin is opened with the IGBT
The output end of pass connects, and the second connection end is connect with the cathode output end, the input terminal of the switch driving circuit and
The signal receiving end connection, the output end of the switch driving circuit are connect with the controlled end of the switching tube；
The switch driving circuit, for according to the received control signal of the signal receiving end, the unlatching of control switch pipe or
Person disconnects.
5. electronic DC switch as claimed in claim 4, which is characterized in that the switching tube is the 2nd IGBT switch, described
The collector of 2nd IGBT switch is connected with the first IGBT emitter switched；The base stage of the 2nd IGBT switch and institute
The output end connection of switch driving circuit is stated, the emitter of the 2nd IGBT switch is connect with the cathode output end；
Alternatively, the switching tube is metal-oxide-semiconductor, the source electrode of the metal-oxide-semiconductor is connect with the first IGBT emitter switched；It is described
Metal-oxide-semiconductor drain electrode is connect with the cathode output end.
6. electronic DC switch as claimed in claim 4, which is characterized in that the freewheeling circuit is diode, two pole
The anode of pipe is connect with the first IGBT emitter switched, and the cathode of the diode is connect with the cathode output end.
7. such as electronic DC switch as claimed in any one of claims 1 to 6, which is characterized in that the electronic DC switch also wraps
Master switch is included, the master switch is connected between the electrode input end and the collector of the first IGBT switch.
8. electronic DC switch as claimed in claim 3, which is characterized in that the electronic DC switch further includes being attached at institute
It states on the first IGBT switch, and for the first radiator to the first IGBT switch heat dissipation；The electronic DC switch is also
Including being attached in the first resistor, and the second radiator for radiating to the first resistor.
9. electronic DC switch as claimed in claim 8, which is characterized in that be also connected with thermistor temperature-sensitive on the radiator
Original part.
10. electronic DC switch as described in claim 1, which is characterized in that the electronic DC switch further include:
Voltage sensor, the voltage sensor are parallel to the input terminal and output end of the electronic DC switch, the voltage
Sensor is also connect with the control terminal；
The output end and cathode output end of the first IGBT switch is connected in series in current sensor, the current sensor,
The current sensor is also connect with the control terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821369039.0U CN208754260U (en) | 2018-08-23 | 2018-08-23 | Electronic DC switch |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821369039.0U CN208754260U (en) | 2018-08-23 | 2018-08-23 | Electronic DC switch |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208754260U true CN208754260U (en) | 2019-04-16 |
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ID=66081029
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201821369039.0U Active CN208754260U (en) | 2018-08-23 | 2018-08-23 | Electronic DC switch |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208754260U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108736873A (en) * | 2018-08-23 | 2018-11-02 | 深圳市德利和能源技术有限公司 | Electronic DC switch |
-
2018
- 2018-08-23 CN CN201821369039.0U patent/CN208754260U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108736873A (en) * | 2018-08-23 | 2018-11-02 | 深圳市德利和能源技术有限公司 | Electronic DC switch |
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