CN102694492A - Device and method for controlling rotational speed of fan - Google Patents
Device and method for controlling rotational speed of fan Download PDFInfo
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- CN102694492A CN102694492A CN2012101703490A CN201210170349A CN102694492A CN 102694492 A CN102694492 A CN 102694492A CN 2012101703490 A CN2012101703490 A CN 2012101703490A CN 201210170349 A CN201210170349 A CN 201210170349A CN 102694492 A CN102694492 A CN 102694492A
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Abstract
A device for controlling the rotational speed of a fan comprises a controller, a switcher and a voltage stabilizer, wherein the controller is used for detecting a rotational speed signal of the fan, generating a first driving signal when the rotational speed of the fan is higher than a scheduled rotational speed signal, and generating the first driving signal and a second driving signal when the rotational speed signal of the fan is lower than the scheduled rotational speed signal; the switcher is in electric connection with the controller, and is used for receiving the first driving signal; and the voltage stabilizer is electrically connected with the controller, the switcher and the fan, and used for receiving the second driving signal. Therefore, the rotational speed of the fan can be controlled according to the first driving signal and the second driving signal.
Description
The present invention is dividing an application of following application for a patent for invention: application number: 200510022967.0, and the applying date: on December 19th, 2005, denomination of invention: the revolution speed control device of fan and method.
Technical field
The present invention relates to a kind of revolution speed control device and method, particularly relate to a kind of revolution speed control device and method of fan.
Background technology
Most electronic system all is equiped with a fan for the usefulness of dispelling the heat, and produces misoperation to prevent this electronic system because of overheated.
As shown in Figure 1, a kind of known fan 1 has a motor 11, if this motor 11 is a DC Brushless Motor, then has a voltage V of rotating speed and this motor 11
MThe character that is directly proportional, if will control the rotating speed of this fan 1, then electrical ties is in this main power source V
CCThis motor 11 can connect in addition again one and can change the linear voltage stabilization assembly 12 of voltage, by a voltage V who changes this linear voltage stabilization assembly 12
T, with this voltage V of this motor 11 of control break
M, and then change the rotating speed of this fan 1, i.e. this voltage V of this motor 11
MBe main power source V
CCDeduct this voltage V of this linear voltage stabilization assembly 12
T(V
M=V
CC-V
T).For example, as this voltage V of this linear voltage stabilization assembly 12
TWhen becoming big, this voltage V of this motor 11 then
MDiminish, make rotating speed slack-off; Yet, though this fan 1 can utilize this voltage V that changes this linear voltage stabilization assembly 12 easily
T, reaching the rotating speed that changes this fan 1, but because this control mode causes power loss to rise, and this linear voltage stabilization assembly 12 also uses and the change of voltage because of long-time, thus be prone to heating, and the difficult situation generation of heat radiation is arranged.
For improving above-mentioned shortcoming, as shown in Figure 2, the motor 21 of another kind of known fan 2, except with main power source V
CCOutside the electrically connect, the power switch assembly 22 of also connecting, and import the conducting of this power switch assembly 22 of a pulse width modulating signal (pulse width modulation) PWM control and the time of not conducting; For instance; When the high level time of the work period of this pulse width modulating signal PWM (duty cycle) is longer; The ON time of this power switch assembly 22 is then longer, and makes the rotating speed of this fan 2 accelerate, and promptly this electronic system is utilized the length of the high and low level time of this pulse width modulating signal PWM; Control the time of the conducting or the not conducting of this power switch assembly 22, to change the rotating speed of this fan 2.But because the noise that this power switch assembly 22 is produced when switching is particularly evident when this fan 2 is the slow-speed of revolution; And it is as shown in Figure 3; This fan 2 can cause the rapid variation of current change quantity (di/dt) of voltage (Δ V) and unit interval when switching, so cause electromagnetic interference to raise.
Hold the above, how a kind of revolution speed control device and the method that power loss, electronics are switched the fan of the noise that produced and electromagnetic interference, one of current just important topic of reducing is provided.
Summary of the invention
In view of above-mentioned problem, the purpose of this invention is to provide a kind of revolution speed control device and method of fan, it reduces power loss, electronics switches noise and the electromagnetic interference that is produced, and has preferable heat dissipation.
According to an aspect of the present invention, a kind of revolution speed control device of fan is provided, comprises that a controller detects a tach signal of this fan; When this tach signal was higher than a desired speed signal, this controller was controlled the rotating speed of this fan according to one first drive signal; And when this tach signal was lower than this desired speed signal, this controller was according to the rotating speed of this first drive signal and this fan of one second drive signal control, wherein when this tach signal is lower than this desired speed signal; The value of this first drive signal is a fixed value, and this fixed value defaults in this controller, at this moment; The rotating speed of said fan is maintained at the minimum speed of said fixed value, and can not continue to diminish, and said revolution speed control device also comprises: a pressurizer; With this controller and this fan electrical ties; When needs further reduce the rotating speed of fan, receive and according to this second drive signal, to control the rotating speed of this fan; Wherein, this controller utilizes the magnitude of voltage of this this second drive signal of pressurizer change to change the rotating speed of fan.
According to a further aspect in the invention, a kind of method for controlling number of revolution of fan is provided, comprises the following steps: to detect a tach signal of this fan by a controller; Judge that this tach signal is higher or lower than a desired speed signal; When this tach signal was higher than this desired speed signal, this controller was according to the rotating speed of this fan of one first drive signal control; And when this tach signal was lower than this desired speed signal, this controller was according to the rotating speed of this first drive signal and this fan of one second drive signal control, wherein when this tach signal is lower than this desired speed signal; The value of this first drive signal is a fixed value, and this fixed value defaults in this controller, at this moment; The rotating speed of said fan is maintained at the minimum speed of said fixed value; And can not continue to diminish, wherein when this tach signal was lower than this desired speed signal, this controller was by a pressurizer; To control the rotating speed of this fan; Wherein, when needs further reduced the rotating speed of fan, the magnitude of voltage that this controller utilizes this pressurizer to change this second drive signal changed the rotating speed of fan.
For realizing above-mentioned purpose, the revolution speed control device of foundation a kind of fan of the present invention comprises a controller, a switch and a pressurizer.This controller detects a tach signal of this fan, when this tach signal is higher than a desired speed signal, produces one first drive signal, and when this tach signal is lower than this desired speed signal, produces this first drive signal and one second drive signal; This switch then with this controller electrically connect, to receive this first drive signal; This pressurizer and this controller, this switch and this fan electrical ties receive this second drive signal, and according to this first drive signal and this second drive signal, to control the rotating speed of this fan.
For realizing above-mentioned purpose; Revolution speed control device according to another kind of fan of the present invention comprises that a controller detects a tach signal of this fan, and when this tach signal was higher than a desired speed signal, this controller was according to one first drive signal; Control the rotating speed of this fan; And when this tach signal was lower than this desired speed signal, this controller was controlled the rotating speed of this fan according to this first drive signal and one second drive signal.
For realizing above-mentioned purpose, comprise the following steps: to detect a tach signal of this fan according to the method for controlling number of revolution of a kind of fan of the present invention by a controller; Judge that this tach signal is higher or lower than a desired speed signal; When this tach signal was higher than this desired speed signal, this controller was according to the rotating speed of this fan of one first drive signal control; And when this tach signal was lower than this desired speed signal, this controller was according to the rotating speed of this first drive signal and this fan of one second drive signal control.
As stated; Because of according to the revolution speed control device of a kind of fan of the present invention and method being combines voltage control and pulse width modulation control,, and utilize a controller to control this pressurizer and this switch promptly in a pressurizer and the switch of electrically connecting between a motor of this fan and the positive-negative power; When the rotating speed of this fan is higher; By this switch of pulse width modulating signal control, controlling the rotating speed of this fan, because that the wind that this moment, this fan running produced is cut sound is bigger; So the noise that this switch switches is also not obvious, can't increase whole noise content; And when the rotating speed of this fan descends, then the value of this pulse width modulating signal is fixed, change with this pressurizer of a voltage control; Then can adjust the rotating speed of this fan lower again, this switch be all very little because of voltage and electric current, and is certain value; So not only reduce the noise that is produced when switching; Magnitude of voltage more significantly reduces electromagnetic interference, and just uses this pressurizer control, owing to not quite just can change the rotating speed of this fan this moment; So help to reduce power loss, more can solve the heat dissipation problem of this pressurizer.
Description of drawings
Fig. 1 is an a kind of sketch map that utilizes the known fan that the linear voltage mode controls rotating speed;
Fig. 2 is an a kind of sketch map that utilizes the known fan of pulse width modulation control rotating speed;
Fig. 3 is that a kind of known power switch module switches the voltage of generation and a sketch map of current waveform;
Fig. 4 is the sketch map according to the revolution speed control device of a kind of fan of preferred embodiment of the present invention;
Fig. 5 is the sketch map according to the revolution speed control device of the another kind of fan of preferred embodiment of the present invention; And
Fig. 6 is the flow chart according to the method for controlling number of revolution of a kind of fan of preferred embodiment of the present invention.
The reference numeral explanation
1 fan, 11 motors
12 linear voltage stabilization assemblies, 2 fans
21 motors, 22 power switch assemblies
3,4 revolution speed control devices, 31 controllers
32 switchs, 33 pressurizers
5 fans
S
1The first drive signal S
2Second drive signal
PWM pulse width modulating signal S
RefThe desired speed signal
S
fTach signal V
CcMain power source
V
MVoltage V
TVoltage
The step of S01-S04 method for controlling number of revolution
Embodiment
Below will revolution speed control device and method according to a kind of fan of preferred embodiment of the present invention be described with reference to relevant drawings, wherein identical assembly will be explained with identical reference marks.
Please with reference to shown in Figure 4, according to the revolution speed control device 3 of a kind of fan 5 of preferred embodiment of the present invention, it comprises a controller 31, a switch 32 and a pressurizer 33.
This controller 31 detects a tach signal S of this fan 5
f, and in this tach signal S
fBe higher than a desired speed signal S
RefThe time, produce one first drive signal S
1And this controller 31 is in this tach signal S
fBe lower than this desired speed signal S
RefThe time, produce this first drive signal S
1And one second drive signal S
2This controller 31 of present embodiment can be an integrated circuit (IC) or a program-controlled single-chip.
In present embodiment, this first drive signal S
1Can a serve as reasons pulse width modulating signal of outside input, and this second drive signal S
2Then can be a voltage regulation signal, and this voltage regulation signal can be a magnitude of voltage.
32 of this switchs and these controller 31 electrically connects are to receive this first drive signal S
1, in present embodiment, this switch 32 can be a derailing switch.
33 of this pressurizers and this controller 31, this switch 32 and this fan 5 electrically connects, and this pressurizer 33 receives the second drive signal S
2, and according to this first drive signal S
1And this second drive signal S
2, to control the rotating speed of this fan 5.This pressurizer 33 of present embodiment can be a voltage stabilizing didoe or a Zener diode.
As this tach signal S
fBe higher than this desired speed signal S
RefThe time, because the electric current that uses is bigger, so this controller 31 is controlled the rotating speed of this fan 5 through this switch 32, this controller 31 is with this second drive signal S at this moment
2Value be made as zero, and this switch 32 receives this first drive signal S
1And,, control the switched conductive of this switch 32 and the time of not conducting, to change the rotating speed of this fan 5 by the work period that this controller 31 produces pulse width modulating signal through this pressurizer 33.
And as this tach signal S
fBe lower than this desired speed signal S
RefThe time; If still control the rotating speed of this fan 5 through this switch 32; Then the work period must be very little; But when the work period was too small, the electric current that then flows through in the unit interval on the motor of this fan 5 was then excessive, so the wind of the noise that is prone to cause the switch of this switch 32 to switch to be produced during than these fan 5 runnings is cut sound also loudly.
For the switch that reduces switch 32 switches the noise that is produced, in the present embodiment, in this tach signal S
fBe lower than this desired speed signal S
RefThe time, this controller 31 is with this first drive signal S
1Value be made as a fixed value, this fixed value is a predetermined minimum pulse width modulation signal, this predetermined minimum pulse width modulation signal then can be preset in earlier in this controller 31 before these fan 5 entrys into service, so in this tach signal S
fBe lower than this desired speed signal S
RefThe time, the rotating speed of this fan 5 is maintained at the minimum speed of predetermined minimum pulse width modulation signal earlier, and can not continue to diminish; When needs further reduce the rotating speed of this fan 5, then utilize this pressurizer 33 to receive this second drive signal S
2, by changing this second drive signal S
2Magnitude of voltage, change the rotating speed of this fan 5; For example, as this second drive signal S
2Magnitude of voltage when becoming big, then the voltage of the motor of this fan 5 then diminishes, the rotating speed of this fan 5 then can continue to reduce.
Please refer again to shown in Figure 5ly, comprise a controller 31, a switch 32 and a pressurizer 33 according to the revolution speed control device 4 of a kind of fan 5 of another preferred embodiment of the present invention.Wherein, this controller 31, this switch 32 and this pressurizer 33 have identical formation and function with the same components of previous embodiment, so repeat no more.The difference of present embodiment and previous embodiment is, this switch 32 and this controller 31 and this fan 5 electrical ties, this pressurizer 33 then with this controller 31 and this fan 5 electrical ties.
This controller 31 detects this tach signal S of this fan 5
f, as this tach signal S
fBe higher than this desired speed signal S
RefThe time, this controller 31 is with this second drive signal S
2Value be made as zero, this controller 31 promptly utilizes this switch 32 according to this first drive signal S
1Control the rotating speed of this fan 5.And as this tach signal S
fBe lower than this desired speed signal S
RefThe time, this controller 31 is with this first drive signal S
1Value be made as a fixed value, and utilize this pressurizer 33 to change this second drive signal S
2Magnitude of voltage, can make this controller 31 simultaneously according to this first drive signal S
1And this second drive signal S
2, to change the rotating speed of this fan 5.
Please with reference to shown in Figure 6, it is the flow chart according to the method for controlling number of revolution of a kind of fan of preferred embodiment of the present invention, comprises that step S01 is to step S04.
In step S01, detect this tach signal S of this fan 5 by this controller 31
f
In step S02, judge this tach signal S
fWhether be higher than this desired speed signal S
Ref
In step S03, as this tach signal S
fBe higher than this desired speed signal S
RefThe time, this controller 31 is according to this first drive signal S
1Control the rotating speed of this fan 5.
In step S04, as this tach signal S
fBe lower than this desired speed signal S
RefThe time, this controller 31 is according to this first drive signal S
1And this second drive signal S
2Control the rotating speed of this fan 5.
Owing to can be applicable to the revolution speed control device (please refer again to Fig. 4 and Fig. 5) of aforesaid fan according to the method for controlling number of revolution of the fan of preferred embodiment of the present invention; And the execution mode of the method for controlling number of revolution of said fans and effect detail in the revolution speed control device of the fan of previous embodiment, so repeat no more in this.
In sum; Because of according to the revolution speed control device of a kind of fan of the present invention and method being combines voltage control and pulse width modulation control,, and utilize a controller to control this pressurizer and this switch promptly in a pressurizer and the switch of electrically connecting between a motor of this fan and the positive-negative power; When the rotating speed of this fan is higher; Then can switch, controlling the rotating speed of this fan, because that the wind that this moment, this fan running produced is cut sound is bigger by the switch of this switch of pulse width modulating signal control; So the noise that this switch switches is also not obvious, can't increase whole noise content; And when the rotating speed of this fan descends, then the value of this pulse width modulating signal is fixed, change with this pressurizer of a voltage control; So can adjust the rotating speed of this fan lower, this switch be all very little because of voltage and electric current, and is certain value; So not only reduce the noise that is produced when switching; Magnitude of voltage more significantly reduces electromagnetic interference, and just uses this pressurizer control, owing to not quite just can change the rotating speed of this fan this moment; So help to reduce power loss, more can solve the heat dissipation problem of this pressurizer.
The above is merely illustrative, but not is limitation of the present invention.Anyly do not break away from spirit of the present invention and category, and, all should be contained in the claim of the present invention its equivalent modifications of carrying out or change.
Claims (14)
1. the revolution speed control device of a fan comprises that a controller detects a tach signal of this fan, when this tach signal is higher than a desired speed signal; This controller is controlled the rotating speed of this fan according to one first drive signal, and when this tach signal is lower than this desired speed signal; This controller is according to the rotating speed of this first drive signal and this fan of one second drive signal control, and wherein when this tach signal was lower than this desired speed signal, the value of this first drive signal was a fixed value; This fixed value defaults in this controller, and at this moment, the rotating speed of said fan is maintained at the minimum speed of said fixed value; And can not continue to diminish
Said revolution speed control device also comprises: a pressurizer; With this controller and this fan electrical ties; When needs further reduce the rotating speed of fan, receive and according to this second drive signal, to control the rotating speed of this fan; Wherein, this controller utilizes the magnitude of voltage of this this second drive signal of pressurizer change to change the rotating speed of fan.
2. revolution speed control device as claimed in claim 1, it also comprises:
One switch with this controller and this fan electrical ties, receives and according to this first drive signal, to control the rotating speed of this fan.
3. revolution speed control device as claimed in claim 1, it also comprises:
One switch is with this controller electrical ties, to receive this first drive signal;
Wherein, this pressurizer and this controller, this switch and this fan electrical ties receive this second drive signal, and control the rotating speed of this fan according to this first drive signal and this second drive signal.
4. like claim 2 or 3 described revolution speed control devices, wherein when this tach signal was higher than this desired speed signal, the value of this second drive signal was zero, and this switch receives and according to the rotating speed of this this fan of first drive signal control.
5. like claim 2 or 3 described revolution speed control devices, wherein this switch is a derailing switch.
6. revolution speed control device as claimed in claim 1, wherein this first drive signal is a pulse width modulating signal or by a pulse width modulating signal of outside input.
7. revolution speed control device as claimed in claim 1, wherein this second drive signal is a voltage regulation signal or a magnitude of voltage.
8. like claim 1 or 3 described revolution speed control devices, wherein this switch receives this first drive signal, and this this second drive signal of pressurizer reception, and this controller is according to the rotating speed of this first drive signal and this fan of this second drive signal control.
9. revolution speed control device as claimed in claim 8, its this fixed value are a predetermined minimum pulse width modulation signal.
10. revolution speed control device as claimed in claim 1, wherein this controller is an integrated circuit or a program-controlled single-chip.
11. like claim 1 or 3 described revolution speed control devices, wherein this pressurizer is a voltage stabilizing didoe or a Zener diode.
12. the method for controlling number of revolution of a fan comprises the following steps:
Detect a tach signal of this fan by a controller;
Judge that this tach signal is higher or lower than a desired speed signal;
When this tach signal was higher than this desired speed signal, this controller was according to the rotating speed of this fan of one first drive signal control; And
When this tach signal was lower than this desired speed signal, this controller was according to the rotating speed of this first drive signal and this fan of one second drive signal control, wherein when this tach signal is lower than this desired speed signal; The value of this first drive signal is a fixed value; This fixed value defaults in this controller, and at this moment, the rotating speed of said fan is maintained at the minimum speed of said fixed value; And can not continue to diminish
Wherein when this tach signal is lower than this desired speed signal; This controller is by a pressurizer, to control the rotating speed of this fan, wherein; When needs further reduced the rotating speed of fan, the magnitude of voltage that this controller utilizes this pressurizer to change this second drive signal changed the rotating speed of fan.
13. method for controlling number of revolution as claimed in claim 12, wherein when this tach signal was higher than this desired speed signal, this controller was by a switch, to control the rotating speed of this fan.
14. method for controlling number of revolution as claimed in claim 12, wherein when this tach signal was higher than this desired speed signal, it was zero that this controller makes the value of this second drive signal, and this second drive signal is sent to this pressurizer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101703490A CN102694492A (en) | 2005-12-19 | 2005-12-19 | Device and method for controlling rotational speed of fan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101703490A CN102694492A (en) | 2005-12-19 | 2005-12-19 | Device and method for controlling rotational speed of fan |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2005100229670A Division CN1988361A (en) | 2005-12-19 | 2005-12-19 | Control device and method for fan rotary speed |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102694492A true CN102694492A (en) | 2012-09-26 |
Family
ID=46859800
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012101703490A Pending CN102694492A (en) | 2005-12-19 | 2005-12-19 | Device and method for controlling rotational speed of fan |
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| Country | Link |
|---|---|
| CN (1) | CN102694492A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10130007B2 (en) | 2014-06-25 | 2018-11-13 | International Business Machines Corporation | Fan control system for a computer system based on a time variable rate of current |
| CN108811431A (en) * | 2017-04-28 | 2018-11-13 | 茂达电子股份有限公司 | Heat dissipation system and heat dissipation system stabilizing method |
| CN109672370A (en) * | 2017-10-13 | 2019-04-23 | 发那科株式会社 | Electric motor drive system with electrical storage device |
| TWI683527B (en) * | 2018-04-25 | 2020-01-21 | 碩天科技股份有限公司 | Volume control device for uninterruptible power system |
-
2005
- 2005-12-19 CN CN2012101703490A patent/CN102694492A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10130007B2 (en) | 2014-06-25 | 2018-11-13 | International Business Machines Corporation | Fan control system for a computer system based on a time variable rate of current |
| US10149407B2 (en) | 2014-06-25 | 2018-12-04 | International Business Machines Corporation | Fan control method for a computer system based on a time variable rate of current |
| US10897832B2 (en) | 2014-06-25 | 2021-01-19 | International Business Machines Corporation | Fan control based on a time-variable rate of current |
| CN108811431A (en) * | 2017-04-28 | 2018-11-13 | 茂达电子股份有限公司 | Heat dissipation system and heat dissipation system stabilizing method |
| CN108811431B (en) * | 2017-04-28 | 2020-04-14 | 茂达电子股份有限公司 | Heat dissipation system and heat dissipation system stabilizing method |
| CN109672370A (en) * | 2017-10-13 | 2019-04-23 | 发那科株式会社 | Electric motor drive system with electrical storage device |
| CN109672370B (en) * | 2017-10-13 | 2020-12-29 | 发那科株式会社 | Motor drive system having electricity storage device |
| TWI683527B (en) * | 2018-04-25 | 2020-01-21 | 碩天科技股份有限公司 | Volume control device for uninterruptible power system |
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Application publication date: 20120926 |
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