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CN1988361A - Fan speed control device and method - Google Patents

Fan speed control device and method Download PDF

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Publication number
CN1988361A
CN1988361A CNA2005100229670A CN200510022967A CN1988361A CN 1988361 A CN1988361 A CN 1988361A CN A2005100229670 A CNA2005100229670 A CN A2005100229670A CN 200510022967 A CN200510022967 A CN 200510022967A CN 1988361 A CN1988361 A CN 1988361A
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Prior art keywords
signal
fan
rotational speed
controller
driving signal
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CNA2005100229670A
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Chinese (zh)
Inventor
邱俊隆
蔡明熹
黄文喜
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Delta Electronics Inc
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Delta Electronics Inc
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Publication date
Application filed by Delta Electronics Inc filed Critical Delta Electronics Inc
Priority to CNA2005100229670A priority Critical patent/CN1988361A/en
Publication of CN1988361A publication Critical patent/CN1988361A/en
Pending legal-status Critical Current

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Abstract

A rotational speed control device of a fan comprises a controller, a switch and a voltage stabilizer. The controller detects a rotating speed signal of the fan, generates a first driving signal when the rotating speed signal is higher than a preset rotating speed signal, and generates the first driving signal and a second driving signal when the rotating speed signal is lower than the preset rotating speed signal; the switcher is electrically connected with the controller to receive the first driving signal; the voltage stabilizer is electrically connected with the controller, the switcher and the fan, receives the second driving signal and controls the rotating speed of the fan according to the first driving signal and the second driving signal.

Description

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 more easily 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 a pulse width modulating signal (pulse width modulation) PWM and control the time of conducting Yu the not conducting of this power switch assembly 22; For instance, when the high level time of the work period of this pulse width modulating signal PWM (dutycycle) is longer, the ON time of this power switch assembly 22 is then longer, and make the rotating speed of this fan 2 accelerate, 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 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.
From the above, how to provide 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.
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.
For achieving the above object, the revolution speed control device according to 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 achieving the above object, 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, when this tach signal is higher than a desired speed signal, this controller is 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 achieving the above object, comprise the following steps: to detect a tach signal of this fan by a controller according to the method for controlling number of revolution of a kind of fan of the present invention; 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 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 controlled the rotating speed of this fan according to this first drive signal and one second drive signal.
As mentioned above, because of revolution speed control device and method according to a kind of fan of the present invention are in conjunction with voltage control and pulse width modulation control, promptly in a pressurizer and the switch of electrically connecting between a motor of this fan and the positive-negative power, and utilize a controller to control this pressurizer and this switch, when the rotating speed of this fan is higher, control this switch by a pulse width modulating signal, to control the rotating speed of this fan, because it is bigger that the wind that this moment, this fan running produced is cut sound, 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 is because voltage and electric current are all very little, and be certain value, so not only reduce the noise that is produced when switching, more significantly reduce electromagnetic interference, and just use this pressurizer to control this moment, because magnitude of voltage not quite just can change the rotating speed of this fan, 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 schematic diagram that utilizes the known fan that the linear voltage mode controls rotating speed;
Fig. 2 is an a kind of schematic diagram 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 schematic diagram of current waveform;
Fig. 4 is the schematic diagram according to the revolution speed control device of a kind of fan of preferred embodiment of the present invention;
Fig. 5 is the schematic diagram 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 bandwidth modulation signals 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
Hereinafter with reference to relevant drawings, revolution speed control device and method according to a kind of fan of preferred embodiment of the present invention are described, wherein identical assembly will be illustrated with identical reference marks.
Please refer to shown in Figure 4ly, 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 by 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 by 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 by this switch 32, then the work period must be very little, but when the work period is too small, then the electric current that flows through in the unit interval on the motor of this fan 5 is then excessive, so the wind of the noise that easily causes 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.
Referring again to shown in Figure 5, 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 refer to shown in Figure 6ly, 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 (referring 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 describe in detail in the revolution speed control device of the fan of previous embodiment, so repeat no more in this.
In sum, because of revolution speed control device and method according to a kind of fan of the present invention are in conjunction with voltage control and pulse width modulation control, promptly in a pressurizer and the switch of electrically connecting between a motor of this fan and the positive-negative power, and utilize a controller to control this pressurizer and this switch, when the rotating speed of this fan is higher, then can control the switch switching of this switch by a pulse width modulating signal, to control the rotating speed of this fan, because it is bigger that the wind that this moment, this fan running produced is cut sound, 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 is because voltage and electric current are all very little, and be certain value, so not only reduce the noise that is produced when switching, more significantly reduce electromagnetic interference, and just use this pressurizer to control this moment, because magnitude of voltage not quite just can change the rotating speed of this fan, so help to reduce power loss, more can solve the heat dissipation problem of this pressurizer.
The above only is an 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 (16)

1、一种风扇的转速控制装置,包括一控制器检测该风扇的一转速信号,于该转速信号高于一预定转速信号时,该控制器依据一第一驱动信号,控制该风扇的转速,而于该转速信号低于该预定转速信号时,该控制器依据该第一驱动信号及一第二驱动信号控制该风扇的转速。1. A speed control device for a fan, comprising a controller to detect a speed signal of the fan, and when the speed signal is higher than a predetermined speed signal, the controller controls the speed of the fan according to a first driving signal, And when the rotation speed signal is lower than the preset rotation speed signal, the controller controls the rotation speed of the fan according to the first driving signal and a second driving signal. 2、如权利要求1所述的转速控制装置,其还包括:2. The speed control device according to claim 1, further comprising: 一切换器,与该控制器及该风扇电连结,接收并依据该第一驱动信号,以控制该风扇的转速。A switcher, electrically connected with the controller and the fan, receives and controls the fan's rotation speed according to the first driving signal. 3、如权利要求2所述的转速控制装置,其还包括:3. The speed control device according to claim 2, further comprising: 一稳压器,与该控制器及该风扇电连结,接收并依据该第二驱动信号,以控制该风扇的转速。A voltage stabilizer is electrically connected with the controller and the fan, receives and controls the fan speed according to the second driving signal. 4、如权利要求1所述的转速控制装置,其还包括:4. The rotational speed control device according to claim 1, further comprising: 一切换器,与该控制器电连结,以接收该第一驱动信号;以及a switch, electrically connected to the controller, to receive the first driving signal; and 一稳压器,与该控制器、该切换器及该风扇电连结,接收该第二驱动信号,并依据该第一驱动信号及该第二驱动信号控制该风扇的转速。A voltage stabilizer is electrically connected with the controller, the switch and the fan, receives the second drive signal, and controls the fan's speed according to the first drive signal and the second drive signal. 5、如权利要求2或4所述的转速控制装置,其中当该转速信号高于该预定转速信号时,该第二驱动信号的值为零,该切换器接收并依据该第一驱动信号控制该风扇的转速。5. The rotational speed control device according to claim 2 or 4, wherein when the rotational speed signal is higher than the predetermined rotational speed signal, the value of the second driving signal is zero, and the switch receives and controls the first driving signal The speed of the fan. 6、如权利要求2或4所述的转速控制装置,其中该切换器为一开关器。6. The rotational speed control device according to claim 2 or 4, wherein the switch is a switch. 7、如权利要求1所述的转速控制装置,其中该第一驱动信号为一脉冲宽度调制信号或由外部输入的一脉冲宽度调制信号。7. The rotational speed control device as claimed in claim 1, wherein the first driving signal is a pulse width modulation signal or a pulse width modulation signal input from outside. 8、如权利要求1所述的转速控制装置,其中该第二驱动信号为一稳压信号或一电压值。8. The rotational speed control device as claimed in claim 1, wherein the second driving signal is a steady voltage signal or a voltage value. 9、如权利要求3或4所述的转速控制装置,其中当该转速信号低于该预定转速信号时,该第一驱动信号的值为一固定值,该切换器接收该第一驱动信号,且该稳压器接收该第二驱动信号,该控制器依据该第一驱动信号及该第二驱动信号控制该风扇的转速。9. The rotational speed control device according to claim 3 or 4, wherein when the rotational speed signal is lower than the predetermined rotational speed signal, the value of the first driving signal is a fixed value, and the switch receives the first driving signal, And the regulator receives the second driving signal, and the controller controls the rotation speed of the fan according to the first driving signal and the second driving signal. 10、如权利要求9所述的转速控制装置,其该固定值为一预定最小脉冲宽度调制信号。10. The rotational speed control device as claimed in claim 9, wherein the fixed value is a predetermined minimum pulse width modulation signal. 11、如权利要求1所述的转速控制装置,其中该控制器为一集成电路或一可程控单芯片。11. The rotational speed control device as claimed in claim 1, wherein the controller is an integrated circuit or a programmable single chip. 12、如权利要求3或4所述的转速控制装置,其中该稳压器为一稳压二极管或一齐纳二极管。12. The rotational speed control device as claimed in claim 3 or 4, wherein the voltage regulator is a Zener diode or a Zener diode. 13、一种风扇的转速控制方法,包括下列步骤:13. A method for controlling the speed of a fan, comprising the following steps: 藉由一控制器检测该风扇的一转速信号;detecting a rotational speed signal of the fan by a controller; 判断该转速信号高于或低于一预定转速信号;judging that the rotational speed signal is higher or lower than a predetermined rotational speed signal; 当该转速信号高于该预定转速信号时,该控制器依据一第一驱动信号控制该风扇的转速;以及When the rotational speed signal is higher than the predetermined rotational speed signal, the controller controls the rotational speed of the fan according to a first driving signal; and 当该转速信号低于该预定转速信号时,该控制器依据该第一驱动信号及一第二驱动信号控制该风扇的转速。When the rotational speed signal is lower than the predetermined rotational speed signal, the controller controls the rotational speed of the fan according to the first driving signal and a second driving signal. 14、如权利要求13所述的转速控制方法,其中当该转速信号高于该预定转速信号时,该控制器藉由一切换器,以控制该风扇的转速。14. The rotational speed control method as claimed in claim 13, wherein when the rotational speed signal is higher than the predetermined rotational speed signal, the controller controls the rotational speed of the fan through a switch. 15、如权利要求13所述的转速控制方法,其中当该转速信号低于该预定转速信号时,该控制器藉由一稳压器,以控制该风扇的转速。15. The rotational speed control method as claimed in claim 13, wherein when the rotational speed signal is lower than the predetermined rotational speed signal, the controller controls the rotational speed of the fan through a voltage regulator. 16、如权利要求15所述的转速控制方法,其中当该转速信号高于该预定转速信号时,该控制器使该第二驱动信号的值为零,并将该第二驱动信号传送至该稳压器。16. The rotational speed control method according to claim 15, wherein when the rotational speed signal is higher than the predetermined rotational speed signal, the controller makes the value of the second driving signal zero and transmits the second driving signal to the Stabilizer.
CNA2005100229670A 2005-12-19 2005-12-19 Fan speed control device and method Pending CN1988361A (en)

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Application Number Priority Date Filing Date Title
CNA2005100229670A CN1988361A (en) 2005-12-19 2005-12-19 Fan speed control device and method

Related Child Applications (1)

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CN2012101703490A Division CN102694492A (en) 2005-12-19 2005-12-19 Device and method for controlling rotating speed of fan

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CN1988361A true CN1988361A (en) 2007-06-27

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103986281A (en) * 2013-02-08 2014-08-13 台达电子工业股份有限公司 DC motor device and DC fan apparatus
CN104767438A (en) * 2015-03-24 2015-07-08 苏州佳世达电通有限公司 Motor control method, motor module using motor control method and radiating device
CN104081303B (en) * 2011-12-14 2016-12-28 博泽沃尔兹堡汽车零部件有限公司 Control equipment, radiator fan arrangement and method for radiator fan

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104081303B (en) * 2011-12-14 2016-12-28 博泽沃尔兹堡汽车零部件有限公司 Control equipment, radiator fan arrangement and method for radiator fan
US9581168B2 (en) 2011-12-14 2017-02-28 Brose Fahrzeugteile Gmbh & Co. Kommanditsellschaft, Wuerzburg Control device for a radiator fan, radiator fan arrangement and method
CN103986281A (en) * 2013-02-08 2014-08-13 台达电子工业股份有限公司 DC motor device and DC fan apparatus
CN104767438A (en) * 2015-03-24 2015-07-08 苏州佳世达电通有限公司 Motor control method, motor module using motor control method and radiating device
CN104767438B (en) * 2015-03-24 2018-03-06 苏州佳世达电通有限公司 Motor control method and apply its motor module and heat abstractor

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Application publication date: 20070627