CN109630448A - A kind of DC fan fault detection circuit - Google Patents
A kind of DC fan fault detection circuit Download PDFInfo
- Publication number
- CN109630448A CN109630448A CN201811327895.4A CN201811327895A CN109630448A CN 109630448 A CN109630448 A CN 109630448A CN 201811327895 A CN201811327895 A CN 201811327895A CN 109630448 A CN109630448 A CN 109630448A
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- Prior art keywords
- fan
- circuit
- comparator
- voltage
- pin
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
Abstract
The present invention relates to a kind of DC fan fault detection circuits; it is made of difference current detection circuit, filter circuit and delay protection circuit; the operating current of DC fan passes through difference current detection circuit; obtain sampled voltage; output is filtered to filter circuit, obtains the voltage signal proportional to DC fan electric current, is exported to delay protection circuit; the failure voltage signal of DC fan is obtained, failure output is carried out.Circuit of the invention effectively can carry out detection alarm with two kinds of malfunctions of stall to the short circuit of fan.
Description
Technical field
The present invention relates to aircraft electrical system failures, belong to electrical safety field.More particularly to a kind of airplane power source low pressure
The current acquisition and fault detection circuit of DC radiation fan.
Background technique
Important component of the airplane power source as more electric aircrafts, reliability are directly related to the safety of entire aircraft.And
Component overheat is closely bound up with the reliability of power supply product, and the thermal design of power supply product and overheating protection are more and more important.Drop
Volume design matched with thermal design can make component work in rated temperature range, once but fan damage, product
Temperature will steeply rise, and eventually lead to damage of product or reduction life of product.The fan failure of airplane power source product detects function
It can be particularly important.
The fault mode of low-voltage direct radiator fan is stalling, can specifically be caused by open circuit with two kinds of factors of stall.Institute
Having fan, electric current is zero under open circuit conditions, and conventional fan starting is 3 times or so of rated current with its electric current when stall, intelligence
Energy fan guarantees that its fault current is less than rated current using soft start and stall current limliting.It can be seen that by fan electrical current
Sampling conditioning can judge whether fan breaks down state.
It is resistance sampling method and Hall sampling method respectively there are two types of current detection technology is popular.Resistance sampling method
At low cost, circuit is simple, but high-power resistance temperature drift is more obvious.Hall sampling method is at high cost, small power consumption, but to small-range
Current measurement errors are larger, and vulnerable to the influence of external magnetic field, and volume is larger.
Summary of the invention
The purpose of the present invention:
The purpose of the present invention is provide a kind of reliable current acquisition and failure for airplane power source low-voltage direct radiator fan
Detection circuit lacks error protection so that power supply problems of excessive heat caused by fan failure to solve airplane power source radiator fan.
The technical scheme adopted by the invention is as follows:
A kind of DC fan fault detection circuit, by difference current detection circuit, filter circuit and delay protection circuit group
At；The operating current of DC fan obtains sampled voltage by difference current detection circuit, and output to filter circuit is filtered
Wave, obtains the voltage signal proportional to DC fan electric current, and output obtains the failure electricity of DC fan to delay protection circuit
Signal is pressed, failure output is carried out.
It is characterized in that, difference current detection circuit by amplifier N1A, acquisition resistance R15-R24, rectifier diode V5-V8,
Shunt capacitance C5 and proportion adjustment resistance R11, R14, R28, R29 composition；
It is in parallel to acquire resistance R15-R24, the electric current of the DC fan of acquisition is converted into voltage signal, rectifier diode
V5, V6 are in parallel, and after V7, V8 are in parallel, then series connection carries out the backward end voltage of amplifier N1A between each acquisition resistance and ground
Lifting, proportion adjustment resistance R14, R11 are connected with amplifier N1A in-phase end pin 3, the R14 other end and acquisition resistor coupled in parallel one end
Be connected, R11 other end ground connection, proportion adjustment resistance R28, R29 be connected with amplifier N1A backward end pin 2, the R28 other end with adopt
Collecting the resistor coupled in parallel other end to be connected, the R29 other end is connected with the output pin 1 of amplifier N1A, and amplifier N1A pin 8 connects 18V power supply,
Amplifier N1A pin 4 is grounded, and the indirect shunt capacitance C5 of amplifier N1A pin 8 and ground collectively constitutes differential amplifier circuit.
It is characterized in that, filter circuit includes resistance R25 and capacitor C7, the output of difference current detection circuit is through resistance
The backward end of the comparator U1A of R25 and delay protection connects, capacitor C7 connect backward end in the comparator U1A of delay protection with
Between ground.
It is characterized in that, delay protection circuit is made of two-stage voltage comparator circuit, wherein comparator U1A and resistance
The charging circuit of R9, capacitor C6 composition, collectively constitutes first order voltage comparator circuit, the VH connection of first order voltage reference signal
To the in-phase end of comparator U1A, comparator U1A pin 8 connects 18V power supply, and pin 4 is grounded, the indirect shunt capacitance of pin 8 and ground
C4, capacitor C6 mono- terminate comparator U1A output pin 1, other end ground connection；The termination of resistance R9 mono- of output delay circuit compares
Device U1A output pin 1, another termination 18V power supply, comparator U1A by the voltage signal proportional to DC fan electric current with
Voltage reference signal VH compares, and obtains the input voltage of second level voltage comparator circuit, is capacitor C6 charge and discharge；
The voltage reference circuit of comparator U1B and resistance R10, voltage-stabiliser tube V5 composition, collectively constitutes the second step voltage and compares
Device circuit, the resistance R10 mono- of voltage reference circuit terminate 18V, the backward end pin 6 of another termination comparator U1B；Voltage reference
The voltage-stabiliser tube V5 forward end of circuit is grounded, the reversed backward end pin 6 for terminating comparator U1B, comparator U1A output pin 1
It is connected to the in-phase end pin 5 of comparator U1B through delay circuit, is further connected between output pin 7 and the 18V power supply of comparator U1B
The output voltage of pull-up resistor R12, comparator U1A and the voltage of voltage regulation of voltage-stabiliser tube V5 codetermine the output electricity of comparator U1B
Ordinary mail number, if when DC fan failure, the outputs level signals of comparator U1B are high level.
It is characterized in that, the DC fan is low-voltage direct fan, its own has the function of stall hiccup protections, and stifled
Turn half of the electric current no more than fan rated operational current that DC fan is flowed through when failure.
It is characterized in that, proportion adjustment resistance R14=R28, R11=R29.
It is characterized in that, amplifier N1A is single supply power supply operational amplifier.
It is characterized in that, the output of DC fan fault detection circuit is low level, indicate that DC fan works normally, it is defeated
Out it is high level, indicates DC fan failure.
Beneficial effects of the present invention:
The current acquisition and fault detection circuit of airplane power source low-voltage direct fan of the invention select single supply power supply
Amplifier eliminates the design of positive and negative power supply circuit, simplifies the complexity of circuit design.Pass through diode concatenated in sample circuit
Voltage lifting is carried out for the backward end of amplifier, can effectively guarantee the difference sampling precision of current signal.Starting fan process electricity
Stream is less than rated current, can be to avoid reporting failure by mistake during startup, and to falling by the delay circuit of first order comparator
The electric currents such as electricity and stall are less than rated current operating condition and carry out Delayed Alarm protection.
Detailed description of the invention
Fig. 1 is fan failure testing principle block diagram
Fig. 2 is difference current detection circuit figure
Fig. 3 is filter circuit and delay protection circuit figure
Specific embodiment
Present invention is further described in detail with reference to the accompanying drawings of the specification.
Fig. 1 is fan failure testing principle block diagram, and system input is system power supply end 28VDC and GND, and system output is event
Hinder alarm output end FAN_ERR and GND.Fan is connected in series in the input terminal of DC fan fault detection circuit.
Fan failure detection plate is broadly divided into 5 functional areas, is difference current detection, filter circuit, delay guarantor respectively
Protection circuit, failure output circuit, power supply and reference circuit.
Fig. 2 is difference current detection circuit, and sampling resistor and rectifier diode are series at fan current supply circuit.Sampling resistor
It is shunted using 10 resistor coupled in parallel, fan electrical current signal is converted into ohmically voltage signal, sampling resistor value is R, fan
When electric current is I0, the differential voltage value of sampling resistor is.Diode is using two strings two and connection type.Diodes in parallel connects can
Make two diode shared fan electrical currents.Diode and sampling resistor flow through power current, can reduce each member by parallel connection
The power consumption of device reduces its temperature rise.For the reliability for improving system, diode is both placed in the front of pcb board with sampling resistor,
And it maintains the circulation of air.
For the design for simplifying power circuit, difference sample circuit uses the operational amplifier of single supply power supply.When amplifier
Input terminal voltage is less than or when close to 0V, amplifier cisco unity malfunction.Therefore it needs to introduce direct current biasing, by amplifier input terminal electricity
Signal is pressed to carry out level lifting.Diode series, which connect, to improve 1.6V simultaneously for amplifier backward end and in-phase end voltage, improve
Difference sampling precision, and do not influence the output voltage values of amplifier.
The voltage signal at sampling resistor both ends, which enters in differential amplifier circuit, to be improved.Conditioning circuit is powered by single supply
Amplifier and differential amplification resistance constitute.Differential amplification resistance R14=R28, R11=R29, and R11 > R14.Amplifier output voltage
For.
Fig. 3 is filter circuit and delay protection circuit figure, is made of two-stage voltage comparator circuit.Wherein U1A is first
Grade comparison circuit, by current sampling data compared with given reference voltage；U1B is second level comparison circuit, by first order comparator
Output level is compared with given reference voltage.
The reference voltage VH of first order comparison circuit is generated by power supply and reference circuit.The selection of VH needs to be less than fan volume
Surely run when difference sample circuit output level, and be greater than short circuit operation when difference sample circuit output level.
The amplifier N1A output of difference current detection circuit is high frequency sawtooth waveform, by the low-pass filtering of R25 and C7 composition
Circuit, the level signal of output smoothing are connected to the reverse input end of first order comparator U1A.When sampled level is greater than with reference to electricity
Usually, comparator exports low level；When sampled level is less than reference level, comparator output terminal is slowly drawn high by 18V through R9,
Capacitor C6 charging.
The reference voltage of second level comparison circuit is generated by zener diode V5.The output of first order comparator U1A is through R9
The inverting input terminal of second level comparator is connected to the delayed charging circuit of C6.When first order comparator U1A output is greater than reference
When level, second level comparator U1B output end draws high output high level, system report failure through R12 by 18V；When the first order compares
When device U1A output end is less than reference level, second level comparator U1B exports low level, and system is normal.
Radiator fan is controllable fan, and Starting mode is soft start, and starting a period of time internal fan current value is less than volume
Constant current value.By adjusting the delayed charging circuit of R9 and C6 composition, the in-phase end level of adjustable second level comparator U1B
Climbing speed avoids reporting fan failure by mistake during startup.
Claims (8)
1. a kind of DC fan fault detection circuit, is made of difference current detection circuit, filter circuit and delay protection circuit；
The operating current of DC fan obtains sampled voltage by difference current detection circuit, and output is filtered to filter circuit, obtains
To the voltage signal proportional to DC fan electric current, output obtains the false voltage letter of DC fan to delay protection circuit
Number, carry out failure output.
2. a kind of DC fan fault detection circuit as described in claim 1, which is characterized in that difference current detection circuit by
Amplifier N1A, acquisition resistance R15~R24, rectifier diode V5~V8, shunt capacitance C5 and proportion adjustment resistance R11, R14,
R28, R29 composition；
It is in parallel to acquire resistance R15~R24, the electric current of the DC fan of acquisition is converted into voltage signal, rectifier diode V5, V6
Parallel connection, after V7, V8 are in parallel, then series connection is lifted the backward end voltage of amplifier N1A between each acquisition resistance and ground,
Proportion adjustment resistance R14, R11 is connected with amplifier N1A in-phase end pin 3, and the R14 other end is connected with acquisition resistor coupled in parallel one end,
R11 other end ground connection, proportion adjustment resistance R28, R29 are connected with amplifier N1A backward end pin 2, the R28 other end and acquisition resistance
The other end in parallel is connected, and the R29 other end is connected with the output pin 1 of amplifier N1A, and amplifier N1A pin 8 connects 18V power supply, amplifier
N1A pin 4 is grounded, and the indirect shunt capacitance C5 of amplifier N1A pin 8 and ground collectively constitutes differential amplifier circuit.
3. a kind of DC fan fault detection circuit as claimed in claim 2, which is characterized in that filter circuit includes resistance
The output of R25 and capacitor C7, difference current detection circuit are connected through the backward end of the comparator U1A of resistance R25 and delay protection,
Capacitor C7 connects between the backward end and ground of the comparator U1A of delay protection.
4. a kind of DC fan fault detection circuit as claimed in claim 3, which is characterized in that delay protection circuit is by two-stage
Voltage comparator circuit composition, wherein the charging circuit of comparator U1A and resistance R9, capacitor C6 composition, collectively constitutes the first order
Voltage comparator circuit, first order voltage reference signal VH are connected to the in-phase end of comparator U1A, and comparator U1A pin 8 connects
18V power supply, pin 4 are grounded, and the indirect shunt capacitance C4 of pin 8 and ground, capacitor C6 mono- terminate comparator U1A output pin 1,
Other end ground connection；The termination comparator U1A output pin 1 of resistance R9 mono- of output delay circuit, another termination 18V power supply, than
Compared with voltage reference signal VH, the second step voltage ratio will be obtained with the proportional voltage signal of DC fan electric current compared with device U1A
It is capacitor C6 charge and discharge compared with the input voltage of device circuit；
The voltage reference circuit of comparator U1B and resistance R10, voltage-stabiliser tube V5 composition collectively constitutes second level voltage comparator electricity
Road, the resistance R10 mono- of voltage reference circuit terminate 18V, the backward end pin 6 of another termination comparator U1B；Voltage reference circuit
Voltage-stabiliser tube V5 forward end ground connection, the reversed backward end pin 6 for terminating comparator U1B, comparator U1A output pin 1 is through prolonging
When circuit connection to comparator U1B in-phase end pin 5, comparator U1B output pin 7 and 18V power supply between be further connected with pull-up
The output level that the output voltage of resistance R12, comparator U1A and the voltage of voltage regulation of voltage-stabiliser tube V5 codetermine comparator U1B is believed
Number, if when DC fan failure, the outputs level signals of comparator U1B are high level.
5. a kind of DC fan fault detection circuit as described in claim 1, which is characterized in that the DC fan is low pressure
DC fan, its own has the function of stall hiccup protections, and the electric current that DC fan is flowed through when stall failure is no more than fan
The half of rated operational current.
6. a kind of DC fan fault detection circuit as claimed in claim 4, which is characterized in that proportion adjustment resistance R14=
R28, R11=R29.
7. a kind of DC fan fault detection circuit as claimed in claim 4, which is characterized in that amplifier N1A is single supply confession
Electric operational amplifier.
8. a kind of DC fan fault detection circuit as claimed in claim 4, which is characterized in that DC fan fault detection electricity
The output on road is low level, indicates that DC fan works normally, and is exported as high level, expression DC fan failure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811327895.4A CN109630448B (en) | 2018-11-09 | 2018-11-09 | Direct current fan fault detection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811327895.4A CN109630448B (en) | 2018-11-09 | 2018-11-09 | Direct current fan fault detection circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109630448A true CN109630448A (en) | 2019-04-16 |
| CN109630448B CN109630448B (en) | 2020-06-09 |
Family
ID=66067596
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811327895.4A Active CN109630448B (en) | 2018-11-09 | 2018-11-09 | Direct current fan fault detection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109630448B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110138057A (en) * | 2019-06-27 | 2019-08-16 | 深圳市辉曜科技有限公司 | Solar charger control circuit and solar charger |
| CN112780591A (en) * | 2021-02-25 | 2021-05-11 | 深圳市科元电气技术有限公司 | Fan control and protection circuit and control method of fan protection circuit |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5448143A (en) * | 1993-11-17 | 1995-09-05 | Dell Usa, L.P. | Sensor for monitoring fan operation in a PC or PC based system |
| JP2000065408A (en) * | 1998-08-19 | 2000-03-03 | Nec Kofu Ltd | Method of detecting fan trouble and its device |
| US6163266A (en) * | 1998-12-08 | 2000-12-19 | Lucent Technologies Inc. | Fan operation detection circuit for a DC fan and method of operation thereof |
| CN101435844A (en) * | 2008-11-14 | 2009-05-20 | 艾默生网络能源有限公司 | Fan failure detection circuit and detection method thereof |
| CN204827996U (en) * | 2015-08-04 | 2015-12-02 | 广东爱迪贝克软件科技有限公司 | Circuit is listened to direct current fan trouble |
| CN107947117A (en) * | 2017-10-23 | 2018-04-20 | 歌尔股份有限公司 | A kind of protection circuit of direct current generator |
-
2018
- 2018-11-09 CN CN201811327895.4A patent/CN109630448B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5448143A (en) * | 1993-11-17 | 1995-09-05 | Dell Usa, L.P. | Sensor for monitoring fan operation in a PC or PC based system |
| JP2000065408A (en) * | 1998-08-19 | 2000-03-03 | Nec Kofu Ltd | Method of detecting fan trouble and its device |
| US6163266A (en) * | 1998-12-08 | 2000-12-19 | Lucent Technologies Inc. | Fan operation detection circuit for a DC fan and method of operation thereof |
| CN101435844A (en) * | 2008-11-14 | 2009-05-20 | 艾默生网络能源有限公司 | Fan failure detection circuit and detection method thereof |
| CN204827996U (en) * | 2015-08-04 | 2015-12-02 | 广东爱迪贝克软件科技有限公司 | Circuit is listened to direct current fan trouble |
| CN107947117A (en) * | 2017-10-23 | 2018-04-20 | 歌尔股份有限公司 | A kind of protection circuit of direct current generator |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110138057A (en) * | 2019-06-27 | 2019-08-16 | 深圳市辉曜科技有限公司 | Solar charger control circuit and solar charger |
| CN110138057B (en) * | 2019-06-27 | 2024-02-02 | 深圳市辉曜科技有限公司 | Solar charger control circuit and solar charger |
| CN112780591A (en) * | 2021-02-25 | 2021-05-11 | 深圳市科元电气技术有限公司 | Fan control and protection circuit and control method of fan protection circuit |
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| Publication number | Publication date |
|---|---|
| CN109630448B (en) | 2020-06-09 |
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