CN104880657A - IGBT device fault detection method and corresponding detection circuit - Google Patents
IGBT device fault detection method and corresponding detection circuit Download PDFInfo
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- CN104880657A CN104880657A CN201410072990.XA CN201410072990A CN104880657A CN 104880657 A CN104880657 A CN 104880657A CN 201410072990 A CN201410072990 A CN 201410072990A CN 104880657 A CN104880657 A CN 104880657A
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- igbt device
- igbt
- programming device
- bonding wire
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Abstract
The invention discloses an IGBT device fault detection method and a corresponding detection circuit. The fault detection method comprises the steps of: S1, arranging comparators corresponding with the number of bonding leads, presetting a comparison value among a plurality of comparators, and setting a programmable device electrically connecting with the plurality of comparators; S2, after an IGBT device is open, measuring the grid voltage value of the IGBT device, and inputting the grid voltage value into the plurality of comparators to compare with the comparison value among the plurality of comparators, the comparators correspondingly feeding back a first signal and a second signal; and S3, outputting a feedback result of the plurality of comparators by the programmable device to generate an output signal. According to the IGBT device fault detection method, without dismounting the IGBT device, whether the bonding leads exist falling off phenomena and the number of leads fallen off can be determined in advance, thereby avoiding falling off of other leads caused by falling off of one lead, and finally avoiding faults of the IGBT device or even system paralysis.
Description
Technical field
The present invention relates to technical field of semiconductors, particularly relate to a kind of fault detection method of IGBT device, and for the testing circuit of the fault detection method that realizes above-mentioned IGBT device.
Background technology
Igbt (abbreviation IGBT module) is more satisfactory wholly-controled device, has that frequency of operation is high, processing power is large and drive the advantages such as simple.IGBT module in power electronic equipment, especially apply in the big-and-middle-sized power apparatus of high frequency more and more extensive.Current module capacity reaches 400A-2400A/1200V-6500V, meets the application requirement of power electronics and power drives field.But the equipment failure that IGBT inefficacy causes often brings huge human and material resources loss.
IGBT module lost efficacy be inside modules fatigue accumulate gradually and with the interactional result of many factors such as outside running environment, relate to the aspect factors such as electricity, heat, machinery.The bonding point of bonding wire and solder layer encapsulation are the positions that IGBT module is the most fragile.At present, researchist bears the performance change after thermal shock to device and a large amount of research work has been carried out in reliability decline, substantially seen clearly the dominant failure mode of IGBT module, perfect device manufacture and module package technique, improve Module Reliability on the whole.
At present, existing method needs to causing the reason of this system failure to judge, judge whether this fault is caused by IGBT module inefficacy after IGBT module fault.But the method can not carry out the forecast in advance of fault, thus cannot reduce the loss caused because of the system failure.Meanwhile, IGBT failure class is more, when judging, needs to carry out failure type judgement by disassembling module.But when disassembling module, require to remove the material such as IGBT module plastic casing and Silica hydrogel, belong to destructive and observe, after having observed failpoint, module cannot use, and cost is higher.In addition, disassemble module when testing, sometimes need to utilize scanning electron microscope equipment, but this equipment price is expensive, investment is comparatively large, and when utilizing scanning electron microscope equipment to observe, need long period sample preparation, and range of observation is limited.
Summary of the invention
In view of this, the invention provides a kind of fault detection method of IGBT device and the testing circuit for the fault detection method that realizes above-mentioned IGBT device.
One of to achieve these goals, the fault detection method of a kind of IGBT device of the present invention, some bonding wires that described IGBT device comprises chip and is electrically connected with described chip, described fault detection method comprises the steps:
S1. the comparer corresponding with described some bonding wire quantity is set, preset the fiducial value in some comparers, described fiducial value is the gate voltage values of IGBT device when coming off the bonding wire of respective numbers, arranges the programming device be electrically connected with described some comparers;
S2. after IGBT device is opened, measure the gate voltage values of IGBT device, gate voltage values is input in some comparers and compares with the fiducial value in comparer, if the gate voltage values measured is more than or equal to corresponding preset value, then corresponding comparer feeds back the first signal to programming device, if the gate voltage values measured is less than corresponding preset value, then corresponding comparer feedback secondary signal is to programming device;
S3. the feedback result of some comparers exports by programming device, generating output signal, and when programming device receives the first signal, then coming off appears in the bonding wire of the output signal representative IGBT device of programming device generation; When programming device receives only secondary signal, then the bonding wire normal operation of the output signal representative IGBT device of programming device generation.
As a further improvement on the present invention, described S1 also comprises: set the judgment value in described programming device, and described judgment value is the minimum radical of the bonding wire of required conducting when ensureing that IGBT device is normally run;
Described S3 also comprises: the radical of the bonding wire of conducting under the grid voltage of measurement compares with judgment value by described programming device, and when being less than this judgment value, programming device turns off IGBT device; When being more than or equal to this judgment value, programming device ensures that IGBT device is in running order.
As a further improvement on the present invention, in described S2, programming device is after IGBT device is opened, and through Preset Time, programming device receives second time signal, the time that the Miller platform voltage that described Preset Time is less than described IGBT device continues.
As a further improvement on the present invention, described programming device is CPLD or FPGA.
For realizing another goal of the invention above-mentioned, the testing circuit of a kind of fault detection method for realizing IGBT device described above of the present invention, described IGBT device comprises chip, and the some bonding wires to be electrically connected with described chip, described testing circuit comprises some comparers parallel with one another, and the programming device to be in series with described some comparers, the quantity of described comparer is corresponding with the quantity of described bonding wire, described some comparers have corresponding fiducial value, described fiducial value is the gate voltage values of IGBT device when coming off the bonding wire of respective numbers.
As a further improvement on the present invention, described programming device has judgment value, and described judgment value is the minimum radical of the bonding wire of required conducting when ensureing that IGBT device is normally run.
As a further improvement on the present invention, described programming device is CPLD or FPGA.
Compared with prior art, the invention has the beneficial effects as follows: the fault detection method of IGBT device of the present invention is without the need to disassembling IGBT device and whether can there is obscission to its bonding wire and the radical that comes off judging in advance, avoid because a lead-in wire comes off and cause other lead-in wire to come off, finally cause the fault of IGBT device, even systemic breakdown.The method is easy to operation, and cost is lower.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, the accompanying drawing that the following describes is only some embodiments recorded in the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the time dependent curve of grid voltage of IGBT device of the present invention, grid voltage change curve when wherein the representative of A curve does not occur that bonding wire comes off, grid voltage change curve when the representative of B curve occurs that bonding wire comes off, and the part in figure and between two of A, B curved intersection straight lines represents the situation of change of Miller platform voltage;
Fig. 2 is the circuit diagram of an embodiment of the part-structure of testing circuit of the present invention.
Embodiment
Technical scheme in the present invention is understood better in order to make those skilled in the art person, below in conjunction with the accompanying drawing in the embodiment of the present invention, technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, should belong to the scope of protection of the invention.
As shown in Figure 1, some the bonding wires that IGBT device comprises chip and is electrically connected with described chip, the position that bonding wire and chip carry out being connected is bonding point, and in real process, bonding point exists the problem of cracking.Namely whether the fault detection method of IGBT device of the present invention is namely for ftractureing to bonding point in IGBT device operational process, and also whether bonding wire comes off and test.
Based on following inventive concept during the fault detection method of IGBT device of the present invention: the bonding wire of IGBT device is when coming off, often there is the skew (such as grid voltage) of certain or some leading electrical parameters, this makes the dynamic waveform of IGBT device depart from normal condition significantly.Therefore, judge the fault of device in advance by the information lain in device dynamic waveform, and then the device avoiding component failure to cause normally cannot run.
Particularly, due to the difference of the thermal expansivity of bonding wire and chip two kinds of different materials in IGBT module, in power cycle procedure, temperature fluctuation makes bonding wire and chip attach station produce alternating thermal stress and lead-in wire themselves bend deformational stress, this will cause bonding wire and chip chamber link position crack and spread gradually, finally cause bonding wire to come off, above-mentioned is the most FAQs causing IGBT device to lose efficacy.Meanwhile, bonding wire comes off and can accelerate other bonding wire and in succession come off, and finally causes IGBT device fault.
Based on foregoing invention design, the fault detection method of IGBT device of the present invention comprises the steps:
S1. the comparer corresponding with described some bonding wire quantity is set, preset the fiducial value in some comparers, described fiducial value is the gate voltage values of IGBT device when coming off the bonding wire of respective numbers, arranges the programming device be electrically connected with described some comparers.
Wherein, when the corresponding fiducial value in some comparers is set, can in advance to IGBT device come off the bonding wire of different radical time grid voltage magnitude of voltage measure.Such as, when come off 1 bonding wire time, corresponding grid voltage is V
1, then the fiducial value arranged in corresponding comparer is V
1; In like manner, when come off 2 bonding wires time, corresponding grid voltage is V
2, then the fiducial value arranged in corresponding comparer is V
2.
Preferably, above-mentioned steps S1 also comprises: set the judgment value in described programming device, and described judgment value is the minimum radical of the bonding wire of required conducting when ensureing that IGBT device is normally run.Whether the object of setting like this is, enable programming device control IGBT device according to the quantity of the bonding wire come off and quit work.Preferably, described programming device can be CPLD or FPGA.
When setting the judgment value of programming device, can detect the bonding wire of IGBT device at the different radical that comes off, thus the quantity of the bonding wire of required minimum radical when determining that IGBT device can normally work.
S2., when the grid voltage of IGBT device reaches threshold voltage, IGBT device is open-minded.After IGBT device is opened, measure the gate voltage values of IGBT device, gate voltage values is input in some comparers and compares with the fiducial value in comparer, if the gate voltage values measured is more than or equal to corresponding preset value, then corresponding comparer feeds back the first signal to programming device, if the gate voltage values measured is less than corresponding preset value, then corresponding comparer feedback secondary signal is to programming device.
Wherein, due to the gate voltage values that the fiducial value in comparer is IGBT device when coming off the bonding wire of certain radical accordingly, when the gate voltage values measured in real time is more than or equal to described fiducial value, then illustrate that certain coming off occurs the bonding wire in IGBT device, the quantity come off is more than or equal to the quantity that the bonding wire corresponding to fiducial value comes off.Now, comparer feeds back the first signal to programming device, and described first signal can be designated as 1.
Thus, when the gate voltage values measured in real time is less than described fiducial value, then illustrate that in IGBT device, obscission does not appear in bonding wire, or the quantity of the bonding wire come off is less than the quantity that the bonding wire corresponding to fiducial value comes off.Now, comparer feedback secondary signal is to programming device, and described secondary signal can be designated as 0.
In addition, in described S2, programming device is after IGBT device is opened, and through Preset Time, programming device receives second time signal, the time that the Miller platform voltage that described Preset Time is less than described IGBT device continues.The object of setting like this is, when there is the phenomenon that bonding wire comes off in IGBT device, Miller platform voltage duration of IGBT device reduces, and degenerates gradually and even disappear.Thus when carrying out through Preset Time carrying out sampling analysis to IGBT device, the grid voltage of measurement well can react the change of described Miller platform voltage, thus is convenient to judge whether bonding wire comes off.
S3. the feedback result of some comparers exports by programming device, generating output signal, and when programming device receives the first signal, then coming off appears in the bonding wire of the output signal representative IGBT device of programming device generation; When programming device receives only secondary signal, then the bonding wire normal operation of the output signal representative IGBT device of programming device generation.
Particularly, as a kind of embodiment, when arranging n comparer, the fiducial value of some comparers is respectively V
1, V
2... V
n.Correspondingly, when some comparers feed back signal to CPLD, the output signal that CPLD generates is 00 ... when 0, represent the bonding wire normal operation of IGBT device.When arbitrary comparer feeds back 1 signal, represent that the bonding wire of IGBT device exists obscission.
Further, described S3 also comprises: the radical of the bonding wire of conducting under the grid voltage of measurement compares with judgment value by described programming device, and when being less than this judgment value, programming device turns off IGBT device; When being more than or equal to this judgment value, programming device ensures that IGBT device is in running order.Setting like this, can play the maximum efficiency of IGBT device.
In addition, the present invention also provides a kind of testing circuit 100 of the fault detection method for realizing IGBT device described above, some bonding wires that wherein said IGBT device comprises chip and is electrically connected with described chip.
The programming device 20 that described testing circuit 100 comprises some comparers 10 parallel with one another and is in series with described some comparers 10, the quantity of described comparer 10 is corresponding with the quantity of described bonding wire, described some comparers 10 have corresponding fiducial value, and described fiducial value is the gate voltage values of IGBT device when coming off the bonding wire of respective numbers.
Described programming device 20 has judgment value, and described judgment value is the minimum radical of the bonding wire of required conducting when ensureing that IGBT device is normally run.Described programming device 20 is CPLD or FPGA.
In sum, the fault detection method of IGBT device of the present invention is without the need to disassembling IGBT device and whether can there is obscission to its bonding wire and the radical that comes off judging in advance, avoid because a lead-in wire comes off and cause other lead-in wire to come off, finally cause the fault of IGBT device, even systemic breakdown.The method is easy to operation, and cost is lower.
To those skilled in the art, obviously the invention is not restricted to the details of above-mentioned one exemplary embodiment, and when not deviating from spirit of the present invention or essential characteristic, the present invention can be realized in other specific forms.Therefore, no matter from which point, all should embodiment be regarded as exemplary, and be nonrestrictive, scope of the present invention is limited by claims instead of above-mentioned explanation, and all changes be therefore intended in the implication of the equivalency by dropping on claim and scope are included in the present invention.Any Reference numeral in claim should be considered as the claim involved by limiting.
In addition, be to be understood that, although this instructions is described according to embodiment, but not each embodiment only comprises an independently technical scheme, this narrating mode of instructions is only for clarity sake, those skilled in the art should by instructions integrally, and the technical scheme in each embodiment also through suitable conjunction, can form other embodiments that it will be appreciated by those skilled in the art that.
Claims (7)
1. a fault detection method for IGBT device, described IGBT device comprise chip and with some bonding wires that described chip is electrically connected, it is characterized in that, described fault detection method comprises the steps:
S1. the comparer corresponding with described some bonding wire quantity is set, preset the fiducial value in some comparers, described fiducial value is the gate voltage values of IGBT device when coming off the bonding wire of respective numbers, arranges the programming device be electrically connected with described some comparers;
S2. after IGBT device is opened, measure the gate voltage values of IGBT device, gate voltage values is input in some comparers and compares with the fiducial value in comparer, if the gate voltage values measured is more than or equal to corresponding preset value, then corresponding comparer feeds back the first signal to programming device, if the gate voltage values measured is less than corresponding preset value, then corresponding comparer feedback secondary signal is to programming device;
S3. the feedback result of some comparers exports by programming device, generating output signal, and when programming device receives the first signal, then coming off appears in the bonding wire of the output signal representative IGBT device of programming device generation; When programming device receives only secondary signal, then the bonding wire normal operation of the output signal representative IGBT device of programming device generation.
2. the fault detection method of IGBT device according to claim 1, it is characterized in that, described S1 also comprises: set the judgment value in described programming device, and described judgment value is the minimum radical of the bonding wire of required conducting when ensureing that IGBT device is normally run;
Described S3 also comprises: the radical of the bonding wire of conducting under the grid voltage of measurement compares with judgment value by described programming device, and when being less than this judgment value, programming device turns off IGBT device; When being more than or equal to this judgment value, programming device ensures that IGBT device is in running order.
3. the fault detection method of IGBT device according to claim 1, it is characterized in that, in described S2, programming device is after IGBT device is opened, through Preset Time, programming device receives second time signal, the time that the Miller platform voltage that described Preset Time is less than described IGBT device continues.
4. the fault detection method of IGBT device according to claim 1, is characterized in that, described programming device is CPLD or FPGA.
5. one kind for realizing the testing circuit of the fault detection method of IGBT device described in claim 1, some bonding wires that described IGBT device comprises chip and is electrically connected with described chip, it is characterized in that, the programming device that described testing circuit comprises some comparers parallel with one another and is in series with described some comparers, the quantity of described comparer is corresponding with the quantity of described bonding wire, described some comparers have corresponding fiducial value, and described fiducial value is the gate voltage values of IGBT device when coming off the bonding wire of respective numbers.
6. the fault detection method of IGBT device according to claim 5, is characterized in that, described programming device has judgment value, and described judgment value is the minimum radical of the bonding wire of required conducting when ensureing that IGBT device is normally run.
7. the fault detection method of IGBT device according to claim 5, is characterized in that, described programming device is CPLD or FPGA.
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| CN201410072990.XA CN104880657B (en) | 2014-02-28 | 2014-02-28 | The fault detection method of IGBT device and circuit is detected accordingly |
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| CN201410072990.XA CN104880657B (en) | 2014-02-28 | 2014-02-28 | The fault detection method of IGBT device and circuit is detected accordingly |
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Cited By (6)
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| CN108347158A (en) * | 2017-01-25 | 2018-07-31 | 通用电气公司 | Circuit protection system and method |
| CN108508342A (en) * | 2018-05-28 | 2018-09-07 | 中国科学院上海微系统与信息技术研究所 | A kind of IGBT short circuit overcurrents detection circuit |
| CN110632490A (en) * | 2019-09-03 | 2019-12-31 | 清华大学 | IGBT module state monitoring device and method |
| CN112986784A (en) * | 2021-04-21 | 2021-06-18 | 国网江西省电力有限公司电力科学研究院 | Abnormity identification method and device for high-power welding type IGBT module |
| CN114002575A (en) * | 2021-11-03 | 2022-02-01 | 华北电力大学 | Method and device for monitoring breaking state of bonding wire of IGBT module |
| US11874341B2 (en) | 2019-06-05 | 2024-01-16 | Hefei University Of Technology | Method for monitoring online state of bonding wire of IGBT module |
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| CN112986784A (en) * | 2021-04-21 | 2021-06-18 | 国网江西省电力有限公司电力科学研究院 | Abnormity identification method and device for high-power welding type IGBT module |
| CN114002575A (en) * | 2021-11-03 | 2022-02-01 | 华北电力大学 | Method and device for monitoring breaking state of bonding wire of IGBT module |
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| CN104880657B (en) | 2018-01-12 |
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Address after: 710016 No. 15 Wenjingbei Road, Jingkai District, Xi'an City, Shaanxi Province Patentee after: Xi'an Zhongche Yongji Electric Co. Ltd. Address before: 710016 No. 15 Wenjingbei Road, Jingkai District, Xi'an City, Shaanxi Province Patentee before: Xi'an Yongdian Electric Co., Ltd. |