CN107598355A - Suitable for the IGBT drive circuit of medium-frequency inverting resistance welding machine inverter - Google Patents
Suitable for the IGBT drive circuit of medium-frequency inverting resistance welding machine inverter Download PDFInfo
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- CN107598355A CN107598355A CN201711046401.0A CN201711046401A CN107598355A CN 107598355 A CN107598355 A CN 107598355A CN 201711046401 A CN201711046401 A CN 201711046401A CN 107598355 A CN107598355 A CN 107598355A
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Abstract
The invention provides a kind of IGBT drive circuit suitable for medium-frequency inverting resistance welding machine inverter, including driving power supply circuit and drive circuit, driving power supply circuit are drive circuitry；The drive circuit includes phototube coupling unit, push-pull amplifier circuit, over-current detection circuit, protection blind area delay circuit, overcurrent judgment circuit, indicating fault output circuit; PWM pulse-width signals pass sequentially through phototube coupling unit, push-pull amplifier circuit, driving resistance connection IGBT grid; IGBT colelctor electrode connection over-current detection circuit; over-current detection circuit is by protecting blind area delay circuit to connect overcurrent judgment circuit, overcurrent judgment circuit output end connecting fault output circuit.The present invention can drive intermediate frequency electric resistance welding inverter complete series IGBT, and electric current is from 200A/1200V to 1200A/1200V；A set of IGBT drive circuit, it can be both used alone when driving middle low power electric resistance welding inverter, and can be used for high power contravariant electrical resistance weld controller IGBT parallel drive occasions again.
Description
Technical field
The invention belongs to medium-frequency inverting resistance welding machine technical field, is applied to medium frequency inverter electric resistance welding more particularly, to one kind
The IGBT drive circuit of machine inverter.
Background technology
In medium frequency inverter electric resistance welding inverter, its key components is the IGBT of 4 composition " H bridges " circuit topological structures,
Its full name of IGBT is insulated gate bipolar transistor, is the core devices changed and controlled for electric energy, is described as power electronics
" heart " of industry and modern unsteady flow industry " jewel on imperial crown ".It is its electric power of reliable and stable performance in IGBT applications
The effect of conversion, IGBT driving is usually the whole system most important thing.Medium frequency inverter electric resistance welding inverter its compare with it is general
Frequency converter, the characteristics of there is its own：Almost there is no the no-load running time, otherwise work, otherwise stop；Within the extremely short time
The output of (3-5ms) electric current will jump to 2000A or so from 0A, and its secondary output current maximum can reach 100000A or so；
In medium frequency inverter electrical resistance weld controller, IGBT work is all an impact process forever, driving failure easily occurs, even " fried
The situation of pipe ".
Due to its it is above-mentioned the characteristics of so that integrated IGBT drive module can not meet medium-frequency resistance welding machine inverter IGBT
Driving requirement.Therefore, it is badly in need of a kind of IGBT drive circuit for meeting medium frequency inverter electric resistance welding inverter.
The content of the invention
In view of this, the present invention is directed to propose a kind of IGBT suitable for medium-frequency inverting resistance welding machine inverter drives electricity
Road, a set of IGBT drive circuit is realized, can both use, and can be used for again high-power inverse in the independent IGBT of driving middle low power
Become electrical resistance weld controller IGBT parallel drive occasions.
To reach above-mentioned purpose, the technical proposal of the invention is realized in this way：
Suitable for the IGBT drive circuit of medium-frequency inverting resistance welding machine inverter, including driving power supply circuit and driving electricity
Road, driving power supply circuit are drive circuitry；The drive circuit includes phototube coupling unit, push-pull amplifier circuit, excessively stream
Detection circuit, protection blind area delay circuit, overcurrent judgment circuit, failure refer to output circuit, and PWM pulse-width signals pass sequentially through
Phototube coupling unit, push-pull amplifier circuit, resistance drive connection IGBT grid, IGBT colelctor electrode connection over-current detection electricity
Road, over-current detection circuit is by protecting blind area delay circuit to connect overcurrent judgment circuit, the connection event of overcurrent judgment circuit output end
Hinder output circuit.
Further, the driving power supply circuit includes the power supply control chip of signal connection, high frequency transformer, whole successively
Current circuit, power supply control chip are responsible for the control of whole power supply, and 24V direct currents are electrically accessed high frequency transformer, and 4 roads of final generation are mutual
The ac square wave of isolation, then the supply voltage of medium frequency inverter resistance spot welding inverter driving circuit is obtained by rectification circuit.
Further, the phototube coupling unit includes optocoupler OP1, and pulse-width signal is passed by optocoupler OP1 3 pins
It is defeated, after isolation, exported by 6 pins.
Further, the push-pull amplifier circuit includes two-stage amplifying circuit and push-pull circuit, the two-stage amplifying circuit
It is the two-stage amplifying circuit being made up of triode T10, triode T11, push-pull circuit is by triode T8, triode T9, three poles
The push-pull circuit that pipe T13, triode T14 are formed.
Further, the over-current detection circuit includes the diode D23 and diode D22 of series connection, diode D22 the moon
Pole connects IGBT colelctor electrode, and diode D23 anode connects the protection blind area delay circuit；The protection blind area delay circuit
Mainly include triode T5, the triode T3 and metal-oxide-semiconductor T6 of positive-negative-positive of positive-negative-positive, diode D23 sun with overcurrent judgment circuit
Pole connects 15V power supplys by the triode T5 of resistance R6 connection positive-negative-positives, triode T5 emitter stage, and triode T5 colelctor electrode leads to
The triode T3 of voltage-stabiliser tube ZD2 connection positive-negative-positives base stage is crossed, triode T3 colelctor electrode connects -5.6V power supplys, triode T3 hair
Emitter-base bandgap grading connection metal-oxide-semiconductor T6 grid, metal-oxide-semiconductor T6 drain electrode and the indirect resistance R21 of source electrode, metal-oxide-semiconductor T6 source electrode connect -5.6V electricity
Source；Metal-oxide-semiconductor T6 drain electrode passes through resistance R24 connecting triodes T9 and triode T14 colelctor electrode, triode T8 and triode
T13 emitter stage connects failure output circuit.
Further, the output end connecting fault indicating circuit of the failure output circuit and failure output optocoupler, failure
Output optocoupler is optocoupler OP2, and failure indicating circuit is LED light；The failure output circuit includes triode T1 and periphery
Circuit, the negative electrode of triode T1 colelctor electrode connection LED light, the anode of LED light connect 15V power supplys by resistance R48；
Triode T1 colelctor electrode connects optocoupler OP2 input simultaneously.
Relative to prior art, the present invention has the advantage that：
(1) present invention can drive intermediate frequency electric resistance welding inverter complete series IGBT, and electric current is from 200A/1200V to 1200A/
1200V；A set of IGBT drive circuit, it can both use, can be used for again high-power inverse in the independent IGBT of driving middle low power
Become electrical resistance weld controller IGBT parallel drive occasions, a set of drive circuit can drive two parallel IGBTs simultaneously.
(2) and with driving high efficient and reliable；The driving failure, wrong report etc. that Integrate Design can be overcome in use lacks
Fall into；Reduce the generation of " bombing " phenomenon to greatest extent, improve the reliability of intermediate frequency electric resistance welding inverter；It is open-minded to add IGBT
Indicator function after failure, that is to say, that failure is opened due to which specific IGBT in actual applications, had directly
Instruction, is easy to search corresponding IGBT.
(3) it is short to calculate IGBT according to actual conditions for single-chip microcomputer breakdown judge interface connection Master control chip Master control chip
Short-circuit number occurs for road, is driven when short-circuit frequently generation and more than or equal to after certain number, instructing this drive circuit to turn off
Dynamic output, to ensure IGBT safety.
Brief description of the drawings
The accompanying drawing for forming the part of the present invention is used for providing a further understanding of the present invention, schematic reality of the invention
Apply example and its illustrate to be used to explain the present invention, do not form inappropriate limitation of the present invention.In the accompanying drawings：
Fig. 1 is the theory diagram that power supply circuit is driven described in the embodiment of the present invention；
Fig. 2 is the theory diagram of drive circuit described in the embodiment of the present invention；
Fig. 3 is the circuit diagram of drive circuit described in the embodiment of the present invention；
Fig. 4 is the schematic diagram of IGBT described in the embodiment of the present invention.
Embodiment
It should be noted that in the case where not conflicting, the feature in embodiment and embodiment in the present invention can phase
Mutually combination.
Describe the present invention in detail below with reference to the accompanying drawings and in conjunction with the embodiments.
Suitable for the IGBT drive circuit of medium-frequency inverting resistance welding machine inverter, including driving power supply circuit and driving electricity
Road, driving power supply circuit are drive circuitry；
As shown in Fig. 2 the drive circuit includes phototube coupling unit, push-pull amplifier circuit, over-current detection circuit, protection
Blind area delay circuit, overcurrent judgment circuit, failure refer to output circuit, PWM pulse-width signals pass sequentially through phototube coupling unit,
The grid of push-pull amplifier circuit, resistance drive connection IGBT, IGBT colelctor electrode connect over-current detection electricity by backward dioded
Road, over-current detection circuit is by protecting blind area delay circuit to connect overcurrent judgment circuit, the connection event of overcurrent judgment circuit output end
Hinder output circuit.
As shown in figure 1, it is described driving power supply circuit include successively signal connection power supply control chip, high frequency transformer,
Rectification circuit, power supply control chip are responsible for the control of whole power supply, and 24V direct currents are electrically accessed high frequency transformer, and 4 tunnels of final generation are mutual
The ac square wave being isolated, then the supply voltage of medium frequency inverter resistance spot welding inverter driving circuit is obtained by rectification circuit.
As shown in figure 3, phototube coupling unit described in the present embodiment includes optocoupler OP1, pulse-width signal passes through optocoupler OP1
3 pins transmission, after isolation, by 6 pins export；
The push-pull amplifier circuit includes two-stage amplifying circuit and push-pull circuit, specifically, optocoupler OP1 output signals are passed through
Triode T10, triode T11 two-stage are output to by triode T8, triode T9, triode T13, triode T14 after amplifying
The push-pull circuit of composition, the further amplification of signal power is carried out, to meet the requirement of IGBT drivings；
The over-current detection circuit includes the diode D23 and diode D22 of series connection, diode D22 negative electrode connection
IGBT colelctor electrode, diode D23 anode connect the protection blind area delay circuit；By D22 pairs of diode D23, diode
IGBT colelctor electrode --- transmitting voltage across poles is monitored.
The protection blind area delay circuit and overcurrent judgment circuit mainly include triode T5, three poles of positive-negative-positive of positive-negative-positive
Pipe T3 and metal-oxide-semiconductor T6, specifically, triode T5 of the diode D23 anode by resistance R6 connection positive-negative-positives, triode T5's
Emitter stage connects 15V power supplys, the base stage for the triode T3 that triode T5 colelctor electrode passes through voltage-stabiliser tube ZD2 connection positive-negative-positives, triode
T3 colelctor electrode connects -5.6V power supplys, triode T3 emitter stage connection metal-oxide-semiconductor T6 grid, metal-oxide-semiconductor T6 drain electrode and source electrode it
Indirect resistance R21, metal-oxide-semiconductor T6 source electrode connect -5.6V power supplys；Metal-oxide-semiconductor T6 drain electrode passes through resistance R24 connecting triodes T9 and three
Pole pipe T14 colelctor electrode, triode T8 and triode T13 emitter stage connect failure output circuit.
Output end connecting fault indicating circuit and failure the output optocoupler of the failure output circuit, failure output optocoupler are
Optocoupler OP2, failure indicating circuit are LED light OK, and LED light is in normal operating conditions, for normal bright state, when with drive
When the IGBT that dynamic circuit is connected produces driving malfunction, LED light OK extinguishes；The failure output circuit includes triode T1
And peripheral circuit, triode T1 colelctor electrode connection LED light OK negative electrode, LED light OK anode pass through resistance R48
Connect 15V power supplys；Triode T1 colelctor electrode connects optocoupler OP2 input simultaneously.
The failure output optocoupler connects the Master control chip of inverter, master control coremaking by single-chip microcomputer breakdown judge interface
Piece calculates IGBT short circuits and short-circuit number occurs, when short circuit frequently occurs and more than or equal to necessarily secondary according to actual conditions
After number, the shut-off driving output of this drive circuit is instructed, to ensure IGBT safety.
The present embodiment devises two-way drive signal because driving two IGBT used in parallel simultaneously, the G1 in Fig. 3,
E1, G2, E2, C exit connect corresponding IGBT G (grid) ends, E (emitter stage) ends and C (colelctor electrode) ends respectively, such as
Shown in Fig. 4.
The course of work of foregoing circuit is：
Colelctor electrode by diode D23, diode D22 to IGBT --- transmitting voltage across poles monitors, when IGBT exists
Its colelctor electrode in the period of conducting --- when the voltage of transmitting interpolar exceeds certain scope, i.e., it is detected as short-circuit condition
Come, then triode T5 is turned on, triode T3 conductings, metal-oxide-semiconductor T6 shut-offs.Corresponding triode T1 shut-offs, IGBT driving conditions
LED light OK extinguishes, and illustrates failure, optocoupler OP2 6 pin ERR output high level.Meanwhile realize to the reliable of IGBT
Shut-off.
It is inverse that the quality of IGBT/gate design is directly connected to the whole medium frequency inverter electric resistance welding being made up of IGBT
Become the longtime running reliability of device system.It is fully saturated that the value of positive grid voltage should make IGBT produce enough, and makes on-state
Loss minimizes, while also answers limiting short-circuit current and power stress caused by it.
The positive grid voltage VGE of IGBT are bigger, and conducting resistance is lower, and loss is smaller.But if VGE is excessive, once IGBT mistakes
Stream, can cause the static state of endophyte IGCT to hold up post effect, cause IGBT to fail.On the contrary, if VGE is too small, may make
IGBT operating point falls into linear amplification region, ultimately results in the mistake cause thermal damage of device.In view of this consideration, it is open-minded in the present invention
When gate drive voltage for 15V or so.
When grid voltage is zero, IGBT is in off-state.Because IGBT turn off process may bear very big dv/
Dt, with shut-off surge, gate off voltage is disturbed, opening by mistake for device may be caused logical.In order to ensure IGBT in colelctor electrode ---
Occur still being held off during dv/dt noises on emitter voltage, it is necessary to apply a reversely shut-off bias on grid, using anti-
Turn-off power loss can be also reduced to bias.Therefore, reverse biased is -5.6V or so in the present invention.
Produced present invention is generally directed to the deficiency that existing integrated drive electronics is used in medium frequency inverter resistance welding inverter
It is raw.Be firstly added the indicator function after IGBT is opened unsuccessfully, that is to say, that due to the present invention in actual applications it is specific which
IGBT's opens failure, has direct instruction, is easy to search corresponding IGBT.The a set of IGBT drive circuit of the present invention, both
It can be used in the independent IGBT of driving middle low power, can be used for high power contravariant electrical resistance weld controller IGBT parallel drives again
Occasion.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
God any modification, equivalent substitution and improvements made etc., should be included in the scope of the protection with principle.
Claims (6)
1. suitable for the IGBT drive circuit of medium-frequency inverting resistance welding machine inverter, it is characterised in that：Including driving power supply circuit
And drive circuit, driving power supply circuit are drive circuitry；
The drive circuit include phototube coupling unit, push-pull amplifier circuit, over-current detection circuit, protection blind area delay circuit,
Overcurrent judgment circuit, indicating fault output circuit, PWM pulse-width signals pass sequentially through phototube coupling unit, recommend amplification electricity
Road, resistance drive connection IGBT grid, IGBT colelctor electrode connection over-current detection circuit, over-current detection circuit are blind by protecting
Area's delay circuit connection overcurrent judgment circuit, overcurrent judgment circuit output end connecting fault output circuit.
2. the IGBT drive circuit according to claim 1 suitable for medium-frequency inverting resistance welding machine inverter, its feature exists
In：The driving power supply circuit includes power supply control chip, high frequency transformer, the rectification circuit of signal connection successively, power supply control
Coremaking piece is responsible for the control of whole power supply, and 24V direct currents are electrically accessed high frequency transformer, the final exchange side for producing 4 tunnels and being mutually isolated
Ripple, then the supply voltage of medium frequency inverter resistance spot welding inverter driving circuit is obtained by rectification circuit.
3. the IGBT drive circuit according to claim 1 suitable for medium-frequency inverting resistance welding machine inverter, its feature exists
In：The phototube coupling unit includes optocoupler OP1, and pulse-width signal is transmitted by optocoupler OP1 3 pins, after isolation, by
6 pins export.
4. the IGBT drive circuit according to claim 1 suitable for medium-frequency inverting resistance welding machine inverter, its feature exists
In：The push-pull amplifier circuit includes two-stage amplifying circuit and push-pull circuit, the two-stage amplifying circuit be by triode T10,
The two-stage amplifying circuit that triode T11 is formed, push-pull circuit is by triode T8, triode T9, triode T13, triode T14
Form.
5. the IGBT drive circuit according to claim 1 suitable for medium-frequency inverting resistance welding machine inverter, its feature exists
In：The over-current detection circuit includes series diode D23 and diode D22, diode D22 negative electrode connection IGBT current collection
Pole, diode D23 anode connect the protection blind area delay circuit；
The protection blind area delay circuit and overcurrent judgment circuit mainly include triode T5, the triode T3 of positive-negative-positive of positive-negative-positive
With metal-oxide-semiconductor T6, diode D23 anode meets 15V by the triode T5 of resistance R6 connection positive-negative-positives, triode T5 emitter stage
Power supply, the base stage for the triode T3 that triode T5 colelctor electrode passes through voltage-stabiliser tube ZD2 connection positive-negative-positives, triode T3 colelctor electrode
Connect -5.6V power supplys, triode T3 emitter stage connection metal-oxide-semiconductor T6 grid, metal-oxide-semiconductor T6 drain electrode and the indirect resistance of source electrode
R21, metal-oxide-semiconductor T6 source electrode connect -5.6V power supplys；Metal-oxide-semiconductor T6 drain electrode passes through resistance R24 connecting triodes T9 and triode T14
Colelctor electrode, triode T8 and triode T13 emitter stage connects failure output circuit.
6. the IGBT drive circuit according to claim 1 suitable for medium-frequency inverting resistance welding machine inverter, its feature exists
In：Output end connecting fault indicating circuit and failure the output optocoupler of the failure output circuit, failure output optocoupler is optocoupler
OP2, failure indicating circuit are LED light；The failure output circuit includes triode T1 and peripheral circuit, triode T1's
Colelctor electrode connects the negative electrode of LED light, and the anode of LED light connects 15V power supplys by resistance R48；Triode T1 current collection
Pole connects optocoupler OP2 input simultaneously；The failure output optocoupler connects the master of inverter by single-chip microcomputer breakdown judge interface
Control chip, Master control chip calculate the number that short circuit occurs for IGBT short circuits, when short circuit frequently occurs and more than or equal to one
After determining number, the drive circuit shut-off driving output is instructed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711046401.0A CN107598355B (en) | 2017-10-31 | 2017-10-31 | IGBT drive circuit suitable for intermediate frequency inverter resistance welder inverter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711046401.0A CN107598355B (en) | 2017-10-31 | 2017-10-31 | IGBT drive circuit suitable for intermediate frequency inverter resistance welder inverter |
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| Publication Number | Publication Date |
|---|---|
| CN107598355A true CN107598355A (en) | 2018-01-19 |
| CN107598355B CN107598355B (en) | 2021-02-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711046401.0A Active CN107598355B (en) | 2017-10-31 | 2017-10-31 | IGBT drive circuit suitable for intermediate frequency inverter resistance welder inverter |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9607354D0 (en) * | 1995-04-05 | 1996-06-12 | Countertone Limited | Electrical welding apparatus |
| CN101104219A (en) * | 2007-06-18 | 2008-01-16 | 华南理工大学 | High frequency contravariant direct-current spot-welding power supply device and its application |
| CN202147087U (en) * | 2011-07-01 | 2012-02-22 | 无锡市南方电器制造有限公司 | Intermediate frequency inversion direct current and variable frequency alternating current resistance welding power supply |
| CN202894547U (en) * | 2012-11-18 | 2013-04-24 | 盐城鼎力达焊接科技有限公司 | Anti-sticking functional circuit for insulated grid bipolar transistor (IGBT) type high-frequency invert direct current (DC) electric welder |
| CN204993289U (en) * | 2015-07-16 | 2016-01-20 | 艾恩格电气（北京）有限公司 | Igbt drive circuit |
-
2017
- 2017-10-31 CN CN201711046401.0A patent/CN107598355B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9607354D0 (en) * | 1995-04-05 | 1996-06-12 | Countertone Limited | Electrical welding apparatus |
| CN101104219A (en) * | 2007-06-18 | 2008-01-16 | 华南理工大学 | High frequency contravariant direct-current spot-welding power supply device and its application |
| CN202147087U (en) * | 2011-07-01 | 2012-02-22 | 无锡市南方电器制造有限公司 | Intermediate frequency inversion direct current and variable frequency alternating current resistance welding power supply |
| CN202894547U (en) * | 2012-11-18 | 2013-04-24 | 盐城鼎力达焊接科技有限公司 | Anti-sticking functional circuit for insulated grid bipolar transistor (IGBT) type high-frequency invert direct current (DC) electric welder |
| CN204993289U (en) * | 2015-07-16 | 2016-01-20 | 艾恩格电气（北京）有限公司 | Igbt drive circuit |
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| CN107598355B (en) | 2021-02-05 |
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