CN1054337A - The protective circuit of high-power darlington transistors - Google Patents

The protective circuit of high-power darlington transistors Download PDF

Info

Publication number
CN1054337A
CN1054337A CN 90107801 CN90107801A CN1054337A CN 1054337 A CN1054337 A CN 1054337A CN 90107801 CN90107801 CN 90107801 CN 90107801 A CN90107801 A CN 90107801A CN 1054337 A CN1054337 A CN 1054337A
Authority
CN
China
Prior art keywords
circuit
comparator
point
protective circuit
darlington
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
CN 90107801
Other languages
Chinese (zh)
Other versions
CN1019344B (en
Inventor
王志良
许大中
郦江
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN 90107801 priority Critical patent/CN1019344B/en
Publication of CN1054337A publication Critical patent/CN1054337A/en
Publication of CN1019344B publication Critical patent/CN1019344B/en
Expired legal-status Critical Current

Links

Images

Landscapes

  • Inverter Devices (AREA)
  • Protection Of Static Devices (AREA)

Abstract

The present invention is the protective circuit of high-power darlington transistors.Its feature is to monitor V simultaneously BE(variation of reflection Ic) and V CECarry out duplicate protection.Protective circuit adopts two comparators to handle V respectively BE, V CESignal when the actual detected value of any signal surpasses set point, all can turn-off Darlington transistor immediately.This circuit adopts the NOR gate integrated circuit to finish the V after the comparison BE, V CEThe logical "or" of signal is handled, and can make the protective circuit action effectively with a d type flip flop again.Adopt the triode of high back-pressure switching diode, magnifying state and the circuit structure of inverter, realize V CESignal Processing.

Description

The protective circuit of high-power darlington transistors
The invention belongs to the circuit emergency protective circuit.
Power transistor (Darlington transistor) has control performance advantage good and that turn-off easily.But its overload capacity is low, needs short-circuit protection; The V of main circuit CEIf depart from normal range (NR), then make Darlington transistor work undesired, these shortcomings once limited its application in power electronics devices, so be anxious to be solved and the general problem of care to the protection of its short-circuit protection and irregular working.
To the short-circuit protection of high-power darlington transistors, newer method is to utilize the base voltage V of Darlington transistor BEMeasure collector current I CVariation, to realize short-circuit protection.Because as base current and junction temperature one timing, the base voltage V of Darlington transistor BE, can be along with collector current I CIncrease increase by the relation of approximate first power, as shown in Figure 1.This short-circuit protection to power transistor, trouble such as exempted the necessary Signal Spacing of additive method, focus on.At present, the existing V that utilizes BEDetect I CProtective circuit, but general drive circuit that is suitable for and protective circuit itself more complicated all, circuit element is more.
About causing V because of some reasons such as external interference CEDepart from normal range (NR), make Darlington transistor be difficult to guarantee the problem of operate as normal, do not find the way that solves at present as yet.
The objective of the invention is to design a kind of protective circuit that is applicable to simple and ripe high-power darlington transistors drive circuit; circuit element is few, simple in structure, reliable operation, easy to use; can short-circuit protection to Darlington transistor, can guarantee operate as normal again.
Main design of the present invention: adopt to I C(by detecting V BEObtain) and V CEThe monitoring of two parameters realizes respectively the short-circuit protection of Darlington transistor and the duplicate protection of its operate as normal of assurance.At first select its V according to Darlington transistor positive sodium safety working area (SOA) BE(by I CDetermine) and V CESet point (protection threshold values), work as V BEAnd V CEArbitrary actual detected value is during greater than corresponding set point, and high-power darlington transistors is turn-offed in the protective circuit action immediately, finishes the function to its protection.
Description of drawings:
Fig. 1 is the I of Darlington transistor C-V BERelation curve.
Fig. 2 is that the Darlington transistor load is drive circuit, main circuit and the protective circuit of pure resistance.Wherein I is that II is a main circuit and the outer part of frame of broken lines is a protective circuit of the present invention in drive circuit, the frame of broken lines in the frame of broken lines.
Fig. 3 is and V CEThe waveform of the relevant each point of detection signal.
Fig. 4 is the three-phase bridge circuit that Darlington transistor constitutes.
Fig. 5 is the U that is used for three-phase bridge circuit 4The processor schematic diagram.
Specify circuit structure scheme of the present invention in conjunction with the embodiments with reference to accompanying drawing.
Example 1: for the present invention is applied in the protective circuit of Darlington transistor load when being pure resistance.
As shown in Figure 2, be the transistor driver circuit that is applicable to fairly simple maturation of the present invention in the frame of broken lines I.In the frame of broken lines II is by large power supply, ohmic load R L, inductance L and the high-power darlington transistors T that will protect 7The main circuit that constitutes.In the drive circuit, control signal makes triode T by photoelectrical coupler 4, T, simultaneously conducting (T 6Turn-off this moment), drive T 7Conducting; Work as T 4, T 5Turn-off (T simultaneously 6Conducting this moment), make T 7Turn-off, this just makes T 7The energy operate as normal is on off state.Part outside frame of broken lines is a protective circuit of the present invention.As mentioned above, the present invention is not only by monitoring V BEProtect the high-power darlington triode, but to V BE(I C) and V CEMonitor duplicate protection Darlington triode simultaneously.Because triode consumed power P=I CV CE, simultaneously to I C(V BE), V CEMonitor, make P all the time less than the permissible value of triode.So just realize protection effectively to the Darlington triode.In protective circuit, V BE, V CEThe actual detected value take from B point in the drive circuit and the C point in the main circuit respectively, the output signal of protective circuit is passed through T 2, T 3Add to A point and B point in the drive circuit simultaneously.At T 7During operate as normal, protective circuit is failure to actuate; Work as T 7I C(V BE) or V CEWhen exceeding normal range of operation, protective circuit is exported high level, adds to A, the B point of drive circuit, makes T 4, T 5Turn-off T 7Turn-off rapidly.According to design of the present invention, adopt particular circuit configurations as follows: to provide a stable+5V power supply by 7805 integrated package of pressure-stabilizing, to guarantee the protective circuit operate as normal.Comparator U 1Two input end signals, one is by R 2And R 4The V that the bleeder circuit that constitutes provides BESet point be added in "-" input, it is by I CThe maximum functional permissible value determine; Another is the V by the input of B point BEThe actual detected value is added in "+" input.Work as V BEActual value is during greater than set point, U 1Output signal is " 1 " (high level), makes U 5(d type flip flop) is output as " 1 ", T 2, T 3Conducting simultaneously makes T 7Turn-off immediately, realize pliotron T 7Short-circuit protection.Comparator U 2Be to be used for handling V CESignal, it also has two input end signals, and one is V CESet point ("+" input), another is V CEActual detected value ("-" input).The V of set point during by conducting CEMaximum permissible value is determined, works as V CEWhen actual value surpasses set point, U 2Be output as " 1 ", make U 5(d type flip flop) is output as " 1 ", T 2, T 3Conducting, T 7Turn-off immediately, also realize protection power transistor T 7Function, make V CEWhen departing from normal range of operation, can in time turn-off T because of some reasons such as external interference 7
Should illustrate, adopt V CEDetected value guarantees to realize the Darlington transistor operate as normal, and difficulty is bigger, needs certain skill during processing.C point signal is the forceful electric power signal in main circuit, and comparator U 2Branch road is to handle weak electric signal, thus strong and weak electricity must be separated, simultaneously again with V CEActual value detect.For this reason, in circuit, adopt high back-pressure switching diode D 1Finish this task.Work as T 7During conducting, the C point is 2~3/ volts low-level, this moment V CEDetected value is delivered to U through C → C ' → C " → C " ' 2"-" input, and unlike V BEDetected value is added in comparator U 1"+" input; Work as T 7During shutoff, the C point is the high voltage of several hectovolts, D 1Partially anti-, be equivalent to C and C ' disconnection.So just reach and not only strong and weak electricity is separated but also V CEThe purpose that input is come out.To V CEThe processing of detected value has skill, V very much CEActual value has three kinds of states: a kind of state is in T 7During shutoff, corresponding C point voltage is very high; Two kinds is at T in addition 7During conducting, i.e. T 7During operate as normal and the state during irregular working.Protective circuit must guarantee at T 7U during shutoff and during operate as normal (conducting) 2Be output as " 0 " (low level), make the drive circuit operate as normal, but must make at T 7In the turn on process, work as V CEOccur requiring comparator U when undesired 2At once output " 1 ", thus turn-off T 7, under abnormal conditions, work to avoid main circuit.This just should make U 2The corresponding relation of "-" input C " ' signal and C, C ', C ", some signal as shown in Figure 3.When being added in the V that C is ordered CEWhen raising to some extent, C ' some current potential increases, and C ", C " ' current potential reduces, and " ' current potential is lower than V as C CEDuring set point, U 2Output switching activity is " 1 " (high level), makes T 2, T 3Conducting, T 7Turn-off.Realization makes V because of some reasons such as external interference CEProtection when departing from normal range (NR) (higher).For obtaining the waveform of corresponding points shown in Figure 3, T 1Must be in magnifying state, R 12/ R 13Ratio should be between (1.1~1.2).And adopt by U 3-R 14-R 15The inverter circuit structure that constitutes makes C, and " ' signal is not a logic level, but the switch analog level, and is above-mentioned to V to guarantee CEThe correct processing of signal.Promptly be to work as T 7During shutoff, C " ' for simulation high level (about 2 volts), not can be low level, otherwise can't handle; Work as T 7During conducting, C " ' be low level slightly, if the V during conducting CEValue raises, then C, and " ' current potential continues to descend, when dropping to and V CEWhen set point equates, comparator U 2Output switching activity be " 1 ", make protective circuit action, realize Darlington transistor T 7Protection.
Usually in main circuit, to go here and there a small inductor L, with restricted passage power transistor T 7Current changing rate, this inductance value is generally 20~40 μ H.Protective circuit V BE(or I C) and V CESet point, can get 2/3 I of Darlington transistor respectively CMWith 2/3 V CEM, I CMWith V CEMBe the transistorized maximum working value that allows.V when Darlington transistor BE, V CEWhen value exceeds normal range of operation, take the relation of logical "or" to protect, make transistorized consumed power be limited to smaller value all the time, conducting is in the place of safety, so protective circuit of the present invention is to T 7Realized protection very effectively.
Reset switch K is used for zero clearing in the protective circuit, and its effect is after the protective circuit action, is refitted in initial condition.
Example 2: for the present invention is applied in the protective circuit of Darlington transistor load when being motor.
Motor load belongs to inductive load, and this moment, protective circuit of the present invention was usually used in the inverter.At this moment, claimed Darlington triode connects the three-phase bridge circuit of being made up of six Darlington transistors into as shown in Figure 4 usually.According to the operation principle of bridge circuit structure and inverter, be under the situation of motor in load, only need three power Darlington transistors of brachium pontis under the inverter are protected, can play whole six the transistorized effects of protection.On the protection strategy, as long as when having a pipe that short circuit or undesired trend are arranged, just can be to descending the T of brachium pontis d, T e, T fThree Darlington transistors are protected simultaneously.In this case, the comparator U in the circuit as shown in Figure 2 1Should there be three, handle the V of three Darlington transistors respectively BESignal; Comparator U 2Also should there be three, handle the V of three Darlington transistors respectively CESignal.Integrated circuit U 4Change the NOR gate that six inputs three are exported into by two inputs, one output, use U 4' expression (is promptly used U 4' replacement U 4), as shown in Figure 5.From integrated package U 4Three road signals of ' output are imported three U simultaneously 5The set terminal of (d type flip flop).So just can guarantee: if there be arbitrary pipe that short circuit or V are arranged CEWhen departing from normal trend, promptly turn-off three pipes of brachium pontis down simultaneously.
In sum, circuit of the present invention is to adopt to monitor V simultaneously BE(I C) and V CEMethod, protect the high-power darlington triode.And only use several integrated circuits and elements such as several low-power transistors and a spot of resistance, electric capacity to constitute, protective circuit, simple in structure, turn-off rapidly, reliable operation, and realize protection very effectively to Darlington transistor.

Claims (6)

1, the protective circuit of high-power darlington transistors is used for protecting the main circuit II Darlington transistor operate as normal that is driven by the drive circuit I, and feature of the present invention is to adopt two comparator U 1And U 2Handle the V of Darlington transistor respectively BE, V CESignal, comparator U 1Two input signals are arranged, and "-" input is by R 2, R 4The V that the bleeder circuit that constitutes provides BESet point, "+" input is through resistance R from drive circuit B point 6, R 5V is provided BEThe actual detected signal, work as V BEActual value is during greater than set point, comparator U 1Be output as " 1 " (high level), make integrated circuit U 5(d type flip flop) is output as " 1 ", makes T 2, T 3Conducting simultaneously, and export the A point and the B point of drive circuit respectively to, make Darlington transistor T 7Turn-off immediately; Comparator U 2Two input signals are also arranged, V CESet point be added in "+" input, by R 1, R 3The bleeder circuit that constitutes provides, and another is V CEThe actual detected value be added in "-" end, from the C point of main circuit through switching diode D 1, C ' point, triode T 1, C " point, C ' " point and resistance R 17To comparator U 2"-" input, work as V CEWhen actual value surpasses set point, from comparator U 2Be output as " 1 ", make U 5(d type flip flop) is output as " 1 ", makes T 2, T 3Conducting simultaneously makes T 7Turn-off immediately.
2, by the described protective circuit of claim 1, it is characterized in that adopting high back-pressure diode D 1, get R 12/ R 13Ratio is 1.1~1.2, triode T 1Be operated in magnifying state, and adopt inverter U 3-R 14-R 15The circuit that constitutes makes comparator U 2"-" input end signal become the switch analog circuit.
3, by the described protective circuit of claim 1, it is characterized in that V BESet point is taken as 2/3 I CM, V CESet point is taken as 2/3 V CEM
4, by the described protective circuit of claim 1, it is characterized in that being provided with reset switch K.
5, by the described protective circuit of claim 1, it is characterized in that need connecing a small inductor L in the main circuit II, value is taken as 20~40 μ H.
6, by the described protective circuit of claim 1, it is characterized in that when constituting bridge circuit structure, adopting three comparator U by six Darlington transistors 1, three comparator U 2, integrated circuit U 4Be the NOR gate of six inputs, three outputs, supporting three d type flip flop U,, make any Darlington transistor that short circuit trend or V be arranged CEWhen departing from normal range (NR), just three Darlington transistors to following brachium pontis carry out turn-off protection simultaneously.
CN 90107801 1990-09-13 1990-09-13 Protective circuit of high-power darlington transistors Expired CN1019344B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 90107801 CN1019344B (en) 1990-09-13 1990-09-13 Protective circuit of high-power darlington transistors

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 90107801 CN1019344B (en) 1990-09-13 1990-09-13 Protective circuit of high-power darlington transistors

Publications (2)

Publication Number Publication Date
CN1054337A true CN1054337A (en) 1991-09-04
CN1019344B CN1019344B (en) 1992-12-02

Family

ID=4880721

Family Applications (1)

Application Number Title Priority Date Filing Date
CN 90107801 Expired CN1019344B (en) 1990-09-13 1990-09-13 Protective circuit of high-power darlington transistors

Country Status (1)

Country Link
CN (1) CN1019344B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101592517B (en) * 2008-05-29 2011-02-23 上海耀华称重系统有限公司 Protection circuit of excitation power supply of weighing sensor
CN109765474A (en) * 2019-01-25 2019-05-17 无锡固电半导体股份有限公司 A kind of test method of Darlington transistor parameter

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101592517B (en) * 2008-05-29 2011-02-23 上海耀华称重系统有限公司 Protection circuit of excitation power supply of weighing sensor
CN109765474A (en) * 2019-01-25 2019-05-17 无锡固电半导体股份有限公司 A kind of test method of Darlington transistor parameter
CN109765474B (en) * 2019-01-25 2021-03-05 无锡固电半导体股份有限公司 Method for testing parameters of Darlington transistor

Also Published As

Publication number Publication date
CN1019344B (en) 1992-12-02

Similar Documents

Publication Publication Date Title
CN106026621B (en) A kind of band avoids the IGBT drive circuit and detection method of short-circuit protection blind area
CN102263544B (en) IGBT driving circuit with electrification protection
CN101399491A (en) Overcurrent protection circuit for photovoltaic DC-to-AC converter
CN109375087A (en) A kind of protection circuit and method with high speed detection IGBT short trouble
CN111884536A (en) Intelligent power module
CN205829455U (en) The IGBT drive circuit of short-circuit protection blind area avoided by a kind of band
CN109659905A (en) A kind of IPM overcurrent and thermal-shutdown circuit
CN101615855A (en) The power circuit of intelligent electrical apparatus release
CN104767368B (en) A kind of highly reliable three-level inverter circuit Current limited Control method
CN110611298A (en) IPM protection system for flywheel energy storage device
CN1054337A (en) The protective circuit of high-power darlington transistors
CN210536599U (en) Multi-path high-speed broadband overcurrent detection circuit for load switch
CN116191368A (en) Protection circuit and direct current system
CN2588658Y (en) Screw bolt pump self-adaption frequency-change driving and electric consumption monitor device
CN212627129U (en) Matrix type IGBT overcurrent protection circuit
CN212305282U (en) IGBT over-current protection circuit and device
CN201584906U (en) Thyristor trigger circuit for neutral point direct-current blocking device of transformer
CN212183102U (en) Low-voltage circuit breaker for lane controller
CN203151083U (en) Short circuit protection circuit of IGBT module
CN220552939U (en) Composite detection circuit based on VDS desaturation detection and DI/DT detection
CN110970884A (en) Brake unit circuit of frequency converter
CN205960631U (en) Motor overload protection device and motor system
CN213151639U (en) Short-circuit protection circuit and system of inverter output H-bridge IGBT
CN110676817A (en) Low-cost design method for realizing upper bridge and lower bridge MOSFET conduction overcurrent detection and protection for low-speed vehicle
CN208522645U (en) Applied to the current-limiting protection circuit in three level active filters

Legal Events

Date Code Title Description
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C06 Publication
PB01 Publication
C13 Decision
GR02 Examined patent application
C14 Grant of patent or utility model
GR01 Patent grant
C19 Lapse of patent right due to non-payment of the annual fee
CF01 Termination of patent right due to non-payment of annual fee