CN105048414A - IGBT (Insulated Gate Bipolar Transistor) protection circuit and protection method in stepping motor driver - Google Patents

IGBT (Insulated Gate Bipolar Transistor) protection circuit and protection method in stepping motor driver Download PDF

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Publication number
CN105048414A
CN105048414A CN201510454264.9A CN201510454264A CN105048414A CN 105048414 A CN105048414 A CN 105048414A CN 201510454264 A CN201510454264 A CN 201510454264A CN 105048414 A CN105048414 A CN 105048414A
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grid
current
circuit
igbt
control circuit
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CN105048414B (en
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高慧斌
马泽龙
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Changchun Institute of Optics Fine Mechanics and Physics of CAS
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Changchun Institute of Optics Fine Mechanics and Physics of CAS
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Abstract

The invention discloses an IGBT (Insulated Gate Bipolar Transistor) protection circuit and protection method in a stepping motor driver, relates to the technical field of motors, and aims to solve the technical problems of low judgment accuracy, short circuit overcurrent fault tolerance time, short IGBT service life and poor reliability in the protection of IGBTs in an existing motor driver. The IGBT protection circuit comprises a control circuit, an overcurrent protection circuit, a current transformer, a grid driver 4, a grid driver 5, IGBTs, grid resistors, grid voltage stabilizing diodes and triodes, wherein the control circuit is connected with the grid drivers and the bases of the triodes; the grid drivers are connected with the grids of the IGBTs through the grid resistors; the collectors of the triodes are connected with the cathodes of the voltage stabilizing diodes; the anodes of the voltage stabilizing diodes are connected with the grids of the IGBTs; the current transformer is connected in series to a motor coil; the output end of the current transformer is connected with the input end of the overcurrent protection circuit; and the output end of the overcurrent protection circuit is connected with the control circuit. Through adoption of the IGBT protection circuit and protection method, the protection times of overcurrent are reduced, and the working efficiencies of the drivers are increased.

Description

IGBT protection circuit and guard method in stepper motor driver
Technical field
The present invention relates to technical field of motors, be specifically related to IGBT over-current protection method and protective circuit in a kind of stepper motor driver.
Background technology
IGBT (InsulatedGateBipolarTransistor, insulated gate bipolar transistor) be a kind of electronic device common in stepper motor driver, for PWM (Pulse-WidthModulation, the pulse-width modulation) power transfer of drive circuit.At work; when the commutation of stepper motor driver pwm power change-over circuit internal current and stepping motor are braked or reversed time; stepping motor inner inductive element meeting releasing reverse electric current; the electric current in IGBT is caused sharply to increase; once current value exceeds the safety operation area of IGBT; IGBT then can be caused to damage, now need stepper motor driver to carry out protectiveness closedown to IGBT.
At present, the guard method of IGBT mainly uses and postpones to detect.When protective circuit detects that in IGBT, electric current is excessive; owing to postponing design not in very first time action; but after the overcurrent time meets preset value; protective circuit sends guard signal to control circuit and protects IGBT; IGBT temporary current fluctuation in safety operation area can be got rid of like this, avoid stepper motor driver frequently to close.
But; due under standard gate voltage driven, the anti-overcurrent time of IGBT is shorter, and protective circuit also can only be carried out in a short period of time detecting and be protected; and during this period of time the di/dt value of IGBT alters a great deal, and the accuracy causing protective circuit to judge is lower.In addition; due to the impact of the Different factor such as stepping motor rotating speed and load inertia; overcurrent time during IGBT work and the amplitude of overcurrent also can be very different; when there is larger overcurrent; even if protective circuit is made a response; overcurrent also can exceed the safety operation area of IGBT within very short time, even if do not cause IGBT to damage like this, also can reduce useful life and the reliability of IGBT then and there.
Summary of the invention
The present invention solves in existing motor driver that to there is judgment accuracy to the protection of IGBT low, and the circuit overcurrent fault-tolerant time is short, IGBT useful life the technical problem such as short and poor reliability.IGBT protection circuit and guard method in a kind of stepper motor driver are provided.
IGBT protection circuit in stepper motor driver, comprises control circuit, current foldback circuit, current transformer, first grid driving, second grid driving, IGBTT1 ~ T4, resistance R1 ~ R4, grid voltage stabilizing didoe D1 ~ D4 and triode Q1 ~ Q4; Described control circuit and first grid drive second grid to drive and the base stage of triode Q1 ~ Q4 is connected;
Described first grid drives and is connected with the grid of IGBTT2 with R2 and IGBTT1 respectively by resistance R1, and second grid is driven through resistance R3 and is connected with the grid of IGBTT4 with R4 and IGBTT3;
The collector electrode of described triode Q1 ~ Q4 is connected with the negative electrode of voltage stabilizing didoe D1 ~ D4, and the anode of voltage stabilizing didoe D1 ~ D4 is connected with the grid of IGBTT1 ~ T4;
Described IGBTT1 ~ T4 and stepping motor coil form H type pwm power change-over circuit; current transformer is connected in stepping motor coil; the output of current transformer is connected with the input of current foldback circuit, and the output of current foldback circuit is connected with control circuit.
The guard method of IGBT protection circuit in stepper motor driver; the method for the pwm power change-over circuit of stepper motor driver inside electric current commutation and stepping motor braking or reversion; the protection of the overcurrent produced, the method is realized by following steps:
Step one, gather by being connected on current transformer on stepping motor coil the electric current flow through in IGBTT1 ~ T4;
Step 2, when current transformer collects the electric current higher than preset value, current foldback circuit sends overcurrent signal to control circuit, the gate drive voltage of IGBTT1 ~ T4 is reduced by reduction voltage circuit after described overcurrent signal being detected by control circuit;
Whether step 3, the overcurrent signal described in determining step two exist, and if not, then the gate drive voltage of IGBTT1 ~ T4 is returned to normal value by control circuit; If so, step 4 is performed;
Step 4, judge whether described overcurrent signal lasts till default time value, and if so, then IGBT closes by control circuit; If not, then the gate drive voltage of IGBTT1 ~ T4 is returned to normal value by control circuit.
The guard method of IGBT protection circuit in stepper motor driver, when there is braking or reversion for stepping motor, produces the protection of overcurrent, adopts following method to realize:
When steps A, stepping motor normally work, the stepping motor tachometer value of control circuit record setting and current value, and the rotating speed recorded and current value are calculated, obtain the feedback current in current stepping motor coil;
Step B, when control circuit receives braking or the reverse signal of stepping motor, the feedback current obtained in step one and the threshold current preset are compared, if described feedback current is higher than threshold current, then control circuit controls to cut out IGBTT1 ~ T4.
Beneficial effect of the present invention: IGBT protection circuit of the present invention, reduces the protection number of times of stepper motor driver to overcurrent less in the short time, improves the operating efficiency of stepper motor driver; Present invention reduces larger overcurrent in the short time and, to the number of shocks of IGBT, improve life-span and the stability of IGBT.
Accompanying drawing explanation
The schematic diagram of the IGBT protection circuit that Fig. 1 provides for embodiments of the invention.
Embodiment
Specific embodiments one, this programme is specifically protected for first kind overcurrent.As shown in figure, this programme mainly comprises control circuit 1, current foldback circuit 2, current transformer 3, first grid driving 4, second grid driving 5, IGBTT1 ~ T4, resistance R1 ~ R4, grid voltage stabilizing didoe D1 ~ D4 and triode Q1 ~ Q4.Wherein control circuit 1 and first grid drive, second grid drives and triode Q1 ~ Q4 base stage connects, first grid drives, second grid is driven through resistance R1 ~ R4 and IGBTT1 ~ T4 grid and connects, triode Q1 ~ Q4 collector electrode is connected with voltage stabilizing didoe D1 ~ D4 negative electrode, voltage stabilizing didoe D1 ~ D4 anode is connected with IGBTT1 ~ T4 grid, IGBTT1 ~ T4 and stepping motor coil form H type pwm power change-over circuit, current transformer 3 is connected in motor coil, the output of current transformer 3 is connected with the input of current foldback circuit 2, the output of current foldback circuit is connected with control circuit 1.
Designed by the configuration of above circuit, comprise the guard method to first kind overcurrent and Equations of The Second Kind overcurrent, and the overcurrent value of the described first kind is lower than the overcurrent value of Equations of The Second Kind; For first kind overcurrent, its main Producing reason comprises the electric current commutation of the inner pwm power change-over circuit of stepper motor driver, and stepping motor is braked or reversion, and the guard method for first kind overcurrent is:
Step one: when IGBT normally works, control circuit 1 controls first grid driving 4, second grid driving) switch is carried out to IGBTT1 ~ T4, current transformer 3 is monitored the electric current flowing through stepping motor coil, and current waveform is converted to voltage waveform and exports current foldback circuit 2 to and contrast with preset voltage value;
Step 2: when stepping motor coil midstream crosses the electric current exceeding normal range (NR), current transformer 3 sends the voltage waveform exceeding normal range (NR) to current foldback circuit 2, current foldback circuit 2 sends protection request to control circuit 1 to control circuit 1 after this voltage being detected, control circuit 1 controls triode Q1 ~ Q4 conducting, make voltage stabilizing didoe D1 ~ D4 conducting, step-down protection operation is carried out to the grid of IGBTT1 ~ T4;
Step 3: if this over-current signal duration exceedes the default overcurrent protection time, then control circuit control gate drives and closes IGBT, carries out protectiveness shutoff to IGBT.
In embodiments of the present invention, after monitoring the overcurrent in IGBT, the grid voltage of IGBT can be lowered, and makes the V of IGBT ce(Collector-EmitterSaturationVoltage, collector electrode-emitter saturation voltage drop) improves, and improves the V of IGBT ceiGBT self the anti-overcurrent time can be extended, also extend the reaction time of current foldback circuit to overcurrent simultaneously, reduce the reaction requirement to current foldback circuit, improve the accuracy that overcurrent is judged.
Grid voltage stabilizing didoe D1 ~ D4 described in present embodiment and triode Q1 ~ Q4 forms reduction voltage circuit.The current settings higher than normal range (NR) described in step 3 is 1.5 ~ 3 times higher than rated current.
For Equations of The Second Kind overcurrent, its main Producing reason comprises braking or the reversion of stepping motor, and the guard method for Equations of The Second Kind overcurrent is:
Steps A, when stepping motor normally works, control circuit 1 record setting stepping motor revolution value and current value, and to record parameter calculate, draw the possible feedback current in instantaneous coil;
Step B, when control circuit receive braking or reverse signal time, to the possible feedback current calculated with preset threshold current compare, if higher than threshold current, then control circuit directly cuts out IGBT.
The threshold current preset described in present embodiment sets according to the difference of the drive motors model adopted.The threshold current preset sets according to the model difference of motor, is generally load current value 5 ~ 8 times.
Specific embodiments two; present embodiment is the specific embodiment protected Equations of The Second Kind overcurrent: stepping motor operationally, because coil is inductive element, can store certain feedback energy; when stepping motor braking or reversion, feedback energy can be calculated as follows:
E r e v = - 104.7 J G e s n N K T ( K E n N 2 + I 2 R a 2 2 K E n N IR a ) - - - ( 1 )
J in formula gesfor the total inertia of stepping motor, n nfor motor speed, K tfor motor torque coefficient, K efor counter electromotive force of motor coefficient, I is stalling current, R afor stepping motor Coil resistance, the R when stepping motor rotates acan be expressed as:
R a＝ωL+r＝9.549n NL+r(2)
In formula, ω is the angular speed of stepping motor, ω=9.549n n, L is stepping motor winding inductance quantity, and r is the static internal resistance of motor coil;
If the ceiling voltage of power supply is U smax, then:
U s·max＝U s+U F(3)
U in formula sfor the rated operational voltage of power supply, U ffor the pumping voltage that feedback energy causes;
There is again power circuit energy storage formula:
E = 1 2 CU 2 - - - ( 4 )
In formula, C is total capacitance in power circuit;
By (4) Shi Ke get:
1 2 CU s · m a x 2 = 1 2 CU s 2 - E r e v - - - ( 5 )
Again by (1), (2), (3), (5) Shi Ke get, the electric current that feedback energy causes in stepping motor coil is:
I r e v = U s 2 + | 2 E r e v C | R a = 209.4 J G e s n N K T C [ K E n N 2 + I 2 ( 9.549 n N L + r ) 2 2 K E n N + IR a ] + U s 2 9.549 n N L + r - - - ( 6 )
From (6) formula, when system parameter is once determining, I revvalue and stepping motor rotating speed n n, total load inertia J gesand stalling current I is relevant;
Consider that [1] formula is parabolic function again, when stalling current I infinitely diminishes, E revreach maximum, that is:
E r e v · m a x | I ≈ 0 = - 52.3 J G e s n N 2 K E K T - - - ( 7 )
The then peak current I that causes in stepping motor coil of feedback energy revmaxfor:
I r e v · m a x = U S 2 + 104.6 J G e s n N 2 K E K T C 9.549 n N L + r - - - ( 8 )
From (8) formula, when system parameter one timing, the peak current I that feedback energy causes in stepping motor coil revmaxonly with stepping motor total load inertia J geswith rotating speed n nrelevant, this electric current represents stepping motor and discharge total load inertia J by the inner inductive element of stepping motor in the process of braking and reverse gesrotating speed n is accelerated to from zero ntime institute's stored energy process.
High rotating speed n is controlled at PWM nthe occasion of motor, I revmaxparticularly can find out in outstanding (8) formula, n nfor quadratic term), although control circuit is protected after can monitoring this electric current in several ways, if total load inertia J gesor rotating speed n nafter reaching certain value, when stepping motor braking or reversion, I revcan exceed the safety operation area of IGBT in very short, protective circuit is difficult to make a response, even if overcurrent does not damage IGBT then and there, also can impact the life-span of IGBT and stability.
In embodiments of the present invention, by monitoring stepping motor total load inertia J geswith rotating speed n nnumerical value, once J geswith n nwhen at least one in two parameters exceedes preset value, once after control circuit receives braking or reverse signal, control gate drives and closes IGBT immediately, reduces the protective reaction time, reduce the impact of higher overcurrent on IGBT life-span and reliability.

Claims (7)

1. IGBT protection circuit in stepper motor driver, comprises control circuit (1), current foldback circuit (2), current transformer (3), first grid driving (4), second grid driving (5), IGBTT1 ~ T4, resistance R1 ~ R4, grid voltage stabilizing didoe D1 ~ D4 and triode Q1 ~ Q4; It is characterized in that;
Described control circuit (1) drives (4) second grid to drive the base stage of (5) and triode Q1 ~ Q4 to be connected with first grid;
Described first grid drives (4) to be connected with the grid of IGBTT2 with R2 and IGBTT1 respectively by resistance R1, and second grid drives (5) to be connected with the grid of IGBTT4 with R4 and IGBTT3 by resistance R3;
The collector electrode of described triode Q1 ~ Q4 is connected with the negative electrode of voltage stabilizing didoe D1 ~ D4, and the anode of voltage stabilizing didoe D1 ~ D4 is connected with the grid of IGBTT1 ~ T4;
Described IGBTT1 ~ T4 and stepping motor coil form H type pwm power change-over circuit; current transformer (3) is connected in stepping motor coil; the output of current transformer (3) is connected with the input of current foldback circuit (2), and the output of current foldback circuit is connected with control circuit (1).
2. IGBT protection circuit in stepper motor driver according to claim 1, is characterized in that, described grid voltage stabilizing didoe D1 ~ D4 and triode Q1 ~ Q4 forms reduction voltage circuit.
3. the guard method of IGBT protection circuit in stepper motor driver according to claim 1 and 2; it is characterized in that; the method for the pwm power change-over circuit of stepper motor driver inside electric current commutation and stepping motor braking or reversion; the protection of the overcurrent produced, the method is realized by following steps:
Step one, gather by being connected on current transformer (3) on stepping motor coil the electric current flow through in IGBTT1 ~ T4;
Step 2, when current transformer collects the electric current higher than preset value, current foldback circuit (2) sends overcurrent signal to control circuit (1), the gate drive voltage of IGBTT1 ~ T4 is reduced by reduction voltage circuit after described overcurrent signal being detected by control circuit (1);
Whether step 3, the overcurrent signal described in determining step two exist, and if not, then the gate drive voltage of IGBTT1 ~ T4 is returned to normal value by control circuit (1); If so, step 4 is performed;
Step 4, judge whether described overcurrent signal lasts till default time value, and if so, then IGBT closes by control circuit; If not, then the gate drive voltage of IGBTT1 ~ T4 is returned to normal value by control circuit (1).
4. IGBT guard method in stepper motor driver according to claim 3, is characterized in that, described grid voltage stabilizing didoe D1 ~ D4 and triode Q1 ~ Q4 forms reduction voltage circuit.
5. IGBT guard method in stepper motor driver according to claim 3, is characterized in that, described in step 3 is 1.5 ~ 3 times of rated current higher than default settings.
6. IGBT guard method in stepper motor driver according to claim 3, is characterized in that, when there is braking or reversion for stepping motor, produces the protection of overcurrent, adopts following method to realize:
When steps A, stepping motor normally work, the stepping motor tachometer value of control circuit (1) record setting and current value, and the rotating speed recorded and current value are calculated, obtain the feedback current in current stepping motor coil;
Step B, when control circuit (1) receives braking or the reverse signal of stepping motor, the feedback current obtained in step one and the threshold current preset are compared, if described feedback current is higher than threshold current, then control circuit (1) controls to cut out IGBTT1 ~ T4.
7. IGBT guard method in stepper motor driver according to claim 6, is characterized in that, described default threshold current sets according to the difference of the drive motors model adopted.
CN201510454264.9A 2015-07-29 2015-07-29 IGBT protection circuit and guard method in stepper motor driver Expired - Fee Related CN105048414B (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106816854A (en) * 2015-11-27 2017-06-09 沈阳高精数控智能技术股份有限公司 A kind of excessively stream cascade protection method of response servo-drive high
CN108599670A (en) * 2018-05-07 2018-09-28 孟晓丽 Speed regulation control method for special frequency converter for heavy-load motor
CN110501601A (en) * 2019-09-26 2019-11-26 中国航空工业集团公司西安飞机设计研究所 A kind of determination device and method of solid state power device short-circuit protection time

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CN102291072A (en) * 2011-07-22 2011-12-21 李军科 Simple and highly-efficient hybrid stepper motor driving device
CN102931960A (en) * 2012-10-24 2013-02-13 华为技术有限公司 IGBT (insulated gate bipolar translator) protection method and protection circuit
CN202772560U (en) * 2012-04-13 2013-03-06 Tcl空调器(中山)有限公司 IGBT current foldback circuit and inductive load control circuit

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070241701A1 (en) * 2006-03-24 2007-10-18 Sanyo Electric Co., Ltd. Motor Drive Circuit
CN201975764U (en) * 2010-04-28 2011-09-14 上海力申科学仪器有限公司 Frequency converter load short circuit protection circuit for centrifugal machine
CN102064535A (en) * 2010-12-01 2011-05-18 深圳市蓝韵实业有限公司 Insulated gate bipolar transistor overcurrent protection self-recovering circuit
CN102097989A (en) * 2011-02-16 2011-06-15 重庆华渝电气仪表总厂 DC (direct current) motor driver
CN102291072A (en) * 2011-07-22 2011-12-21 李军科 Simple and highly-efficient hybrid stepper motor driving device
CN202772560U (en) * 2012-04-13 2013-03-06 Tcl空调器(中山)有限公司 IGBT current foldback circuit and inductive load control circuit
CN102931960A (en) * 2012-10-24 2013-02-13 华为技术有限公司 IGBT (insulated gate bipolar translator) protection method and protection circuit

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106816854A (en) * 2015-11-27 2017-06-09 沈阳高精数控智能技术股份有限公司 A kind of excessively stream cascade protection method of response servo-drive high
CN108599670A (en) * 2018-05-07 2018-09-28 孟晓丽 Speed regulation control method for special frequency converter for heavy-load motor
CN110501601A (en) * 2019-09-26 2019-11-26 中国航空工业集团公司西安飞机设计研究所 A kind of determination device and method of solid state power device short-circuit protection time
CN110501601B (en) * 2019-09-26 2021-10-22 中国航空工业集团公司西安飞机设计研究所 Device and method for determining short-circuit protection time of solid-state power device

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