US20050242761A1 - Driving circuit for a dc brushless fan motor - Google Patents
Driving circuit for a dc brushless fan motor Download PDFInfo
- Publication number
- US20050242761A1 US20050242761A1 US10/834,927 US83492704A US2005242761A1 US 20050242761 A1 US20050242761 A1 US 20050242761A1 US 83492704 A US83492704 A US 83492704A US 2005242761 A1 US2005242761 A1 US 2005242761A1
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- pin
- control unit
- transistor
- motor
- resistor
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
- H02P6/34—Modelling or simulation for control purposes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S388/00—Electricity: motor control systems
- Y10S388/923—Specific feedback condition or device
Definitions
- the present invention relates to a driving circuit for a DC brushless fan motor; more particularly, relates to a temperature sensor to sense the ambient temperature and feed it back to the motor to control its rotation rate.
- a motor control circuit of the prior art comprises a control unit G, wherein the first and the second pin is connected with a Hall element A.
- the sixth pin is connected with the ninth pin through a motor B.
- the motor B is connected with a diode D.
- the diode D is connected with a first resistor E and the fourteenth pin.
- the fourteenth pin is connected with a second resistor F.
- the second resistor F is connected with the Hall element A.
- the motor control circuit can control the on and off of the motor B, it is only a simple control circuit comprising a diode, a first resistor, the fourteenth pin of the control unit and the motor. So, if the ambient temperature of the motor B is too high, the control circuit may not be able to respond accordingly and the control unit G may receive the overheating signal of the motor B and it may result in thermal shutdown.
- the main purpose of the present invention is to sense the ambient temperature by the temperature sensor and a proper current is fed back to control the rotation rate of the motor.
- the present invention is a driving circuit for a DC brushless fan motor, comprising a control unit, a motor, a Hall element, a signal output unit, a temperature control circuit, a reverse protection circuit and a counter-electromotive force (CEMF) removal circuit, wherein an LB1868M chip is taken as a preferred embodiment for the control unit according to the present invention, which is by no means for any limitation.
- the control unit of the present invention can be made by way of System on Chip (SOC), Single Chip or Hardware Script Language (HSL).
- the ambient temperature is sensed by the temperature sensor and is fed back to the system that a proper current is offered to control the rotation rate of the motor.
- FIG. 1 is a block diagram showing the architecture according to the present invention
- FIG. 2 is a circuit diagram showing the architecture according to the present invention.
- FIG. 3 is a circuit diagram of the control unit according to the present invention.
- FIG. 4 is a circuit diagram showing the control of a DC brushless fan motor according to the prior art.
- the present invention is a driving circuit for a DC brushless fan motor, comprising a control unit 10 , a motor 13 , a Hall element 11 , a signal output unit 10 a , a temperature control circuit 10 b , a reverse protection circuit 10 c , a counter-electromotive force (CEMF) removal circuit 10 d , and a connector 18 , as tied in with a plurality of transistors, diodes, resistors and capacitors.
- CEMF counter-electromotive force
- the control unit 10 can be an LB1868M chip or a single chip with similar function, which is the processing center of the control circuit.
- the motor is connected with the control unit 10 .
- the Hall element 11 is connected with the control unit 10 to detect the position of the motor rotor.
- the signal output unit 10 a is connected with the control unit 10 to notify the outside (such as a computer) whether the motor 13 is running.
- the temperature control circuit 10 b is connected with the control unit 10 to adjust the rotation rate of the motor 13 according to different ambient temperatures as tied in with the connected second transistor 192 (MOSFET).
- the reverse protection circuit 10 c is connected with the motor 13 to avoid reverse voltage feedback.
- the counter-electromotive force (CEMF) removal circuit 10 d is connected with the control unit 10 to prevent other components from damage owing to the transient CEMF made by the motor 13 .
- CEMF counter-electromotive force
- the first pin (IN ⁇ ) of the control unit 10 is connected with the fourth pin (IN ⁇ ) of the Hall element 11 .
- the Hall element 11 is to detect the position of the rotor of the motor 13 .
- the second pin (IN+) of the control unit 10 is connected with the second pin (IN+) of the Hall element.
- the third pin (CT) of the control unit 10 is connected with a first capacitor 141 and the third pin of the Hall element 11 .
- the sixth pin (OUT 1 ) of the control unit is connected with a first and a second Zener diodes 151 , 152 to form a CEMF removal circuit 10 d .
- the first and the second Zener diodes 151 , 152 are connected with the motor 13 and the motor 13 is connected with a first diode 161 , where a reverse protection circuit 10 c is obtained.
- the second resistor 172 is connected with the collector of a third transistor 193 .
- the emitter of the third transistor 193 is grounded.
- the base of the third transistor is connected with a third Zener diode 153 .
- the collector of the third transistor 193 is connected with the second resistor through the base of a fourth transistor.
- the emitter of the fourth transistor is grounded.
- the collector of the fourth transistor 194 is connected with the third pin of the connector 18 to form a signal output unit 10 a .
- the first and the second Zener diodes 151 , 152 are connected with a first resistor 171 .
- the first resistor 171 is connected with the emitter of a first transistor 191 .
- the emitter of the first transistor 191 is connected with a second diode 162 .
- the temperature control circuit 10 b is connected with the temperature sensor 12 and the third resistor 173 .
- the base of the first transistor 191 is connected with a fourth resistor 174 and the second transistor 192 .
- the collector of the first transistor 191 is connected with the second transistor 192 and a fifth and a sixth resistors 175 , 176 .
- the fifth and the sixth resistors 175 , 176 are connected with the second pin of the connector 18 and are grounded.
- the sixth resister 176 is connected with the second diode 162 .
- the seventh pin (GND) of the control unit is connected with a first capacitor 141 , the third pin of the Hall element 11 and the second transistor 192 (MOSFET).
- the seventh pin is connected with the second transistor 192 through a second capacitor 142 .
- the second capacitor is connected with an eighth and a ninth resistor 178 , 179 .
- the ninth resistor 179 is connected with the first pin of the Hall element 11 .
- the ninth pin (OUT 2 ) of the control unit is connected with the motor 13 .
- the tenth pin (Z 1 ) of the control unit 10 is connected with the eleventh one (Z 2 ).
- the thirteenth pin (RD) of the control unit 10 is connected with a seventh resistor 177 .
- the seventh resistor 177 is connected with a first diode 161 , a second and a third resistors 172 , 173 and the temperature sensor 12 , and is connected with the first pin of the connector 18 .
- the second capacitor 142 is connected with the eighth resistor 178 .
- the thirteenth pin (RD) of the control unit 10 is also connected with the signal output unit 10 a to notify the outside (such as a computer) whether the motor 13 is running.
- the outside such as a computer
- the RD is about 12v when the motor 13 stops; 0v, when it is running; and, 5 ⁇ 6v, when it is running in low rotation rate. If this part of circuit is omitted, the outside equipment may misapprehend the motor as not running. So, the signal output unit 10 a is added in the present invention to solve the problem.
- the rotation rate of the motor can be adjusted according to different ambient temperatures.
- the MOSFET is an n-channel enhanced MOSFET, which is normally off. When V GS is equal to 0V, in order to gain drain current, the gate voltage must be over the threshold voltage.
- the temperature sensor with negative temperature coefficient (NTC) is used in the present invention, as tied in with the temperature control circuit, to adjust the bias voltage of the MOSFET, and to further control the drain voltage degree so that the rotation rate of the motor can be under control.
- a driving circuit for a DC brushless fan motor is constructed.
- the control unit 10 When the power is on, a signal is immediately sent to the control unit 10 and the control unit 10 is booted up to produce half-wave control signals to control the motor 13 .
- the motor When the motor is running, by the Hall element 11 and the temperature sensor 12 , the running status of the motor is sensed and adjusted to keep the ambient temperature, wherein the motor is under control more efficiently by the combination of the above circuit components.
- the above circuit components can have further series or parallel connections with some basic circuit components (such as capacitors, resistors, diodes, transistors) to improve actual applications to meet special requests (such as matching).
Abstract
Description
- The present invention relates to a driving circuit for a DC brushless fan motor; more particularly, relates to a temperature sensor to sense the ambient temperature and feed it back to the motor to control its rotation rate.
- As is known, a motor control circuit of the prior art (as shown in
FIG. 4 ) comprises a control unit G, wherein the first and the second pin is connected with a Hall element A. The sixth pin is connected with the ninth pin through a motor B. The motor B is connected with a diode D. The diode D is connected with a first resistor E and the fourteenth pin. The fourteenth pin is connected with a second resistor F. And the second resistor F is connected with the Hall element A. Accordingly, a motor control circuit is constructed. - Although the motor control circuit can control the on and off of the motor B, it is only a simple control circuit comprising a diode, a first resistor, the fourteenth pin of the control unit and the motor. So, if the ambient temperature of the motor B is too high, the control circuit may not be able to respond accordingly and the control unit G may receive the overheating signal of the motor B and it may result in thermal shutdown.
- Therefore, the main purpose of the present invention is to sense the ambient temperature by the temperature sensor and a proper current is fed back to control the rotation rate of the motor.
- To achieve the above purpose, the present invention is a driving circuit for a DC brushless fan motor, comprising a control unit, a motor, a Hall element, a signal output unit, a temperature control circuit, a reverse protection circuit and a counter-electromotive force (CEMF) removal circuit, wherein an LB1868M chip is taken as a preferred embodiment for the control unit according to the present invention, which is by no means for any limitation. The control unit of the present invention can be made by way of System on Chip (SOC), Single Chip or Hardware Script Language (HSL).
- Accordingly, the ambient temperature is sensed by the temperature sensor and is fed back to the system that a proper current is offered to control the rotation rate of the motor.
- The present invention will be better understood from the following detailed description of preferred embodiment of the invention, taken in conjunction with the accompanying drawings, in which:
-
FIG. 1 is a block diagram showing the architecture according to the present invention; -
FIG. 2 is a circuit diagram showing the architecture according to the present invention; -
FIG. 3 is a circuit diagram of the control unit according to the present invention; and -
FIG. 4 is a circuit diagram showing the control of a DC brushless fan motor according to the prior art. - The following descriptions of the preferred embodiment are provided to understand the features and the structures of the present invention.
- Please refer to
FIG. 1 tillFIG. 3 , which are a control circuit diagram, a circuit diagram of the control circuit and a circuit diagram of the control unit, according to the present invention. As shown in the figures, the present invention is a driving circuit for a DC brushless fan motor, comprising acontrol unit 10, amotor 13, aHall element 11, asignal output unit 10 a, atemperature control circuit 10 b, areverse protection circuit 10 c, a counter-electromotive force (CEMF)removal circuit 10 d, and aconnector 18, as tied in with a plurality of transistors, diodes, resistors and capacitors. Thereby, through sensing the running temperature of themotor 13 by atemperature sensor 12 and feeding it back to themotor 13, an adequate current is offered as tied in with a current limiting resistor to control the rotation rate of the motor and the ambient temperature. - The
control unit 10 can be an LB1868M chip or a single chip with similar function, which is the processing center of the control circuit. The motor is connected with thecontrol unit 10. TheHall element 11 is connected with thecontrol unit 10 to detect the position of the motor rotor. Thesignal output unit 10 a is connected with thecontrol unit 10 to notify the outside (such as a computer) whether themotor 13 is running. Thetemperature control circuit 10 b is connected with thecontrol unit 10 to adjust the rotation rate of themotor 13 according to different ambient temperatures as tied in with the connected second transistor 192 (MOSFET). Thereverse protection circuit 10 c is connected with themotor 13 to avoid reverse voltage feedback. The counter-electromotive force (CEMF)removal circuit 10 d is connected with thecontrol unit 10 to prevent other components from damage owing to the transient CEMF made by themotor 13. - Concerning the control circuit according to the present invention, the first pin (IN−) of the
control unit 10 is connected with the fourth pin (IN−) of theHall element 11. TheHall element 11 is to detect the position of the rotor of themotor 13. The second pin (IN+) of thecontrol unit 10 is connected with the second pin (IN+) of the Hall element. The third pin (CT) of thecontrol unit 10 is connected with afirst capacitor 141 and the third pin of theHall element 11. - The sixth pin (OUT1) of the control unit is connected with a first and a second Zener
diodes CEMF removal circuit 10 d. The first and the second Zenerdiodes motor 13 and themotor 13 is connected with afirst diode 161, where areverse protection circuit 10 c is obtained. Thesecond resistor 172 is connected with the collector of athird transistor 193. The emitter of thethird transistor 193 is grounded. The base of the third transistor is connected with a third Zenerdiode 153. The collector of thethird transistor 193 is connected with the second resistor through the base of a fourth transistor. The emitter of the fourth transistor is grounded. The collector of thefourth transistor 194 is connected with the third pin of theconnector 18 to form asignal output unit 10 a. The first and the second Zenerdiodes first resistor 171. Thefirst resistor 171 is connected with the emitter of afirst transistor 191. The emitter of thefirst transistor 191 is connected with asecond diode 162. Through thesecond diode 162, thetemperature control circuit 10 b is connected with thetemperature sensor 12 and thethird resistor 173. The base of thefirst transistor 191 is connected with afourth resistor 174 and thesecond transistor 192. The collector of thefirst transistor 191 is connected with thesecond transistor 192 and a fifth and asixth resistors sixth resistors connector 18 and are grounded. Thesixth resister 176 is connected with thesecond diode 162. - The seventh pin (GND) of the control unit is connected with a
first capacitor 141, the third pin of theHall element 11 and the second transistor 192 (MOSFET). The seventh pin is connected with thesecond transistor 192 through asecond capacitor 142. The second capacitor is connected with an eighth and aninth resistor ninth resistor 179 is connected with the first pin of theHall element 11. The ninth pin (OUT2) of the control unit is connected with themotor 13. The tenth pin (Z1) of thecontrol unit 10 is connected with the eleventh one (Z2). The thirteenth pin (RD) of thecontrol unit 10 is connected with aseventh resistor 177. Theseventh resistor 177 is connected with afirst diode 161, a second and athird resistors temperature sensor 12, and is connected with the first pin of theconnector 18. Through the fourteenth pin (VIN) of thecontrol unit 10, thesecond capacitor 142 is connected with theeighth resistor 178. - The thirteenth pin (RD) of the
control unit 10 is also connected with thesignal output unit 10 a to notify the outside (such as a computer) whether themotor 13 is running. Take the LB1868M chip in thecontrol unit 10 as an example. The RD is about 12v when themotor 13 stops; 0v, when it is running; and, 5˜6v, when it is running in low rotation rate. If this part of circuit is omitted, the outside equipment may misapprehend the motor as not running. So, thesignal output unit 10 a is added in the present invention to solve the problem. - By using the LB1868M chip of the
control unit 10 according to the present invention, as tied in with the second transistor 192 (MOSFET) and thetemperature sensor 12 and thetemperature control circuit 10 b, the rotation rate of the motor can be adjusted according to different ambient temperatures. The MOSFET is an n-channel enhanced MOSFET, which is normally off. When VGS is equal to 0V, in order to gain drain current, the gate voltage must be over the threshold voltage. The temperature sensor with negative temperature coefficient (NTC) is used in the present invention, as tied in with the temperature control circuit, to adjust the bias voltage of the MOSFET, and to further control the drain voltage degree so that the rotation rate of the motor can be under control. By doing so, the ambient temperature of the motor is sensed and the rotation rate is further under control to keep the ambient temperature. Accordingly, by the above circuit components, a driving circuit for a DC brushless fan motor is constructed. When the power is on, a signal is immediately sent to thecontrol unit 10 and thecontrol unit 10 is booted up to produce half-wave control signals to control themotor 13. When the motor is running, by theHall element 11 and thetemperature sensor 12, the running status of the motor is sensed and adjusted to keep the ambient temperature, wherein the motor is under control more efficiently by the combination of the above circuit components. And, the above circuit components can have further series or parallel connections with some basic circuit components (such as capacitors, resistors, diodes, transistors) to improve actual applications to meet special requests (such as matching). - The preferred embodiment herein disclosed is not intended to unnecessarily limit the scope of the invention. Therefore, simple modifications or variations belonging to the equivalent of the scope of the claims and the instructions disclosed herein for a patent are all within the scope of the present invention.
Claims (8)
Priority Applications (1)
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US10/834,927 US6956342B1 (en) | 2004-04-30 | 2004-04-30 | Driving circuit for a DC brushless fan motor |
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US10/834,927 US6956342B1 (en) | 2004-04-30 | 2004-04-30 | Driving circuit for a DC brushless fan motor |
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US20050242761A1 true US20050242761A1 (en) | 2005-11-03 |
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Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050264250A1 (en) * | 2004-05-28 | 2005-12-01 | Datech Technology Co., Ltd. | Driving circuit for a two-phase DC brushless fan motor |
US20080272720A1 (en) * | 2007-05-03 | 2008-11-06 | Atmel Corporation | Accurate motor speed control |
US20100291858A1 (en) * | 2008-02-04 | 2010-11-18 | Delta T Corporation | Automatic control system for ceiling fan based on temperature differentials |
AU2010214786B2 (en) * | 2008-03-06 | 2013-10-17 | Aspen Motion Technologies, Inc | Fan Control System with Sensors |
WO2016038850A1 (en) * | 2014-09-11 | 2016-03-17 | パナソニックIpマネジメント株式会社 | Brushless motor and washing machine provided with same |
US11268528B2 (en) | 2007-10-10 | 2022-03-08 | Delta T, Llc | Ceiling fan system with brushless motor |
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TWM289021U (en) * | 2005-09-23 | 2006-03-21 | Tze-Chiuan Lin | Simplified temperature controller of cooling fan |
DE102006058955B4 (en) * | 2006-12-12 | 2014-07-24 | DüRR DENTAL AG | Suction device for dental, medical and industrial purposes |
US7498755B2 (en) * | 2007-03-01 | 2009-03-03 | Microchip Technology Incorporated | Brushed motor control with voltage boost for reverse and braking |
CN104303065B (en) * | 2012-06-29 | 2017-04-12 | 旭化成微电子株式会社 | Hall electromotive force correction device and hall electromotive force correction method |
US9225272B2 (en) * | 2013-03-04 | 2015-12-29 | Asia Vital Components Co., Ltd. | Control circuit for speed and rotational direction of fan |
CN105332936B (en) | 2014-08-12 | 2017-09-19 | 台达电子工业股份有限公司 | Fan control device |
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US5764020A (en) * | 1996-04-04 | 1998-06-09 | Sgs-Thomson Microelectronics, S.R.L. | Method and apparatus for synchronous driving of the phase windings of a DC motor |
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-
2004
- 2004-04-30 US US10/834,927 patent/US6956342B1/en not_active Expired - Fee Related
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US5764020A (en) * | 1996-04-04 | 1998-06-09 | Sgs-Thomson Microelectronics, S.R.L. | Method and apparatus for synchronous driving of the phase windings of a DC motor |
US5969491A (en) * | 1997-07-15 | 1999-10-19 | Stmicroelectronics S.R.L. | Detection of instantaneous position of the rotor of a brushless DC motor driven in a tripolar mode |
US6236175B1 (en) * | 1998-10-08 | 2001-05-22 | Gate S.P.A. | Process and device for detecting the speed of rotation of a DC electric motor controlled by a PWM control signal |
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Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050264250A1 (en) * | 2004-05-28 | 2005-12-01 | Datech Technology Co., Ltd. | Driving circuit for a two-phase DC brushless fan motor |
US7091689B2 (en) * | 2004-05-28 | 2006-08-15 | Datech Technology Co., Ltd. | Driving circuit for a two-phase DC brushless fan motor |
US20080272720A1 (en) * | 2007-05-03 | 2008-11-06 | Atmel Corporation | Accurate motor speed control |
US11268528B2 (en) | 2007-10-10 | 2022-03-08 | Delta T, Llc | Ceiling fan system with brushless motor |
US20100291858A1 (en) * | 2008-02-04 | 2010-11-18 | Delta T Corporation | Automatic control system for ceiling fan based on temperature differentials |
US8900041B2 (en) | 2008-02-04 | 2014-12-02 | Delta T Corporation | Automatic control system for ceiling fan based on temperature differentials |
AU2010214786B2 (en) * | 2008-03-06 | 2013-10-17 | Aspen Motion Technologies, Inc | Fan Control System with Sensors |
WO2016038850A1 (en) * | 2014-09-11 | 2016-03-17 | パナソニックIpマネジメント株式会社 | Brushless motor and washing machine provided with same |
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