Apparatuses for controlling operation of a motor of a fan assembly based on an induced voltage or a back electromotive force

Patent metadata

Field	Value
Publication number	US-9695832-B2
Application number	US-201414462821-A
Country	US
Kind code	B2
Filing date	Aug 19, 2014
Priority date	Nov 13, 2008
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

An integrated circuit for controlling operation of a motor of a fan assembly. The fan assembly includes a housing and a fan. The motor is in the housing. The housing is void of sensors. The motor is configured to rotate the fan. The integrated circuit includes a detection module and a first control module. The detection module is separate from the fan assembly. The detection module is configured to detect a voltage induced in a first coil of the motor or a back electromotive force received from the first coil of the motor. The first control module is configured to receive a control signal from a second control module and control the operation of the fan based on (a) the control signal, and (b) the voltage induced in the first coil of the motor or the back electromotive force. The second control module is separate from the integrated circuit.

First claim

What is claimed is:

1. An integrated circuit for controlling operation of a motor of a fan assembly, wherein the fan assembly comprises a housing and a fan, wherein the motor is in the housing, and wherein the motor is configured to rotate the fan, the integrated circuit comprising:
a detection module separate from the fan assembly, wherein the detection module is configured to, without receiving a signal from a sensor, detect (i) a voltage induced in a first coil of the motor, wherein the first coil is an undriven coil; and
a first control module configured to (i) receive a control signal from a second control module, and (ii) control the operation of the motor of the fan assembly to control a speed of the fan based on (a) the control signal, and (b) the voltage induced in the first coil of the motor, wherein the second control module is separate from the integrated circuit,
wherein the first control module is further configured to
determine the speed of the fan and positions of stator poles based on the voltage induced in the first coil of the motor,
compare the speed of the fan to a predetermined speed,
if the speed of the fan is not equal to the predetermined speed, proceed with determining whether the motor is stuck and the fan is not rotating,
wherein the determining of whether the motor is stuck and the fan is not rotating is based on (i) a waveform of a back electromotive force received from the first coil of the motor, and (ii) the positions of stator poles, and
if the motor is stuck and the fan is not rotating, refrain from adjusting the speed of the fan.

2. The integrated circuit of claim 1 , wherein:
the first control module is configured to (i) receive a signal from a sensor of the fan assembly, and (ii) based on the signal from the sensor, adjust the speed of the fan; and
the fan assembly comprises the sensor.

3. The integrated circuit of claim 1 , wherein the detection module is configured to, independent of signals transmitted from one or more sensors to the integrated circuit, detect (i) the voltage induced in the first coil of the motor, or (ii) the back electromotive force received from the first coil of the motor.

4. An integrated circuit for controlling operation of a motor of a fan assembly, wherein the fan assembly comprises a housing and a fan, wherein the motor is in the housing, wherein the housing is void of sensors, and wherein the motor is configured to rotate the fan, the integrated circuit comprising:
a detection module separate from the fan assembly, wherein the detection module is configured to detect a voltage induced in a first coil of the motor, wherein the first coil is an undriven coil; and
a first control module configured to (i) receive a control signal from a second control module, and (ii) control the operation of the motor of the fan assembly to control a speed of the fan based on (a) the control signal, and (b) the voltage induced in the first coil of the motor, wherein the second control module is separate from the integrated circuit,
wherein the first control module is further configured to
determine the speed of the fan and positions of stator poles based on the voltage induced in the first coil of the motor,
compare the speed of the fan to a predetermined speed,
if the speed of the fan is not equal to the predetermined speed, proceed with determining whether the motor is stuck and the fan is not rotating,
wherein the determining of whether the motor is stuck and the fan is not rotating is based on (i) a waveform of a back electromotive force received from the first coil of the motor, and (ii) the positions of stator poles, and
if the motor is stuck and the fan is not rotating, refrain from adjusting the speed of the fan.

5. The integrated circuit of claim 4 , wherein:
the detection module is connected to the fan assembly via a first set of conductors; and
the first control module is connected to the second control module via a second set of conductors.

6. The integrated circuit of claim 4 , further comprising a power module configured to supply power to a second coil to generate the voltage induced in the first coil of the motor.

7. The integrated circuit of claim 6 , wherein the power module is configured to supply the power to the second coil while not supplying power to the first coil.

8. The integrated circuit of claim 6 , wherein the detection module and the power module are both connected to the fan assembly via a plurality of wires and an interface.

9. The integrated circuit of claim 4 , wherein the first control module is configured to, based on the voltage induced in the first coil of the motor or the back electromotive force received from the first coil of the motor, control (i) a speed of the fan, or (ii) a direction the fan is rotating.

10. The integrated circuit of claim 4 , wherein:
the first control module is configured to (i) detect a position of the fan based on the voltage induced in the first coil of the motor or the back electromotive force received from the first coil of the motor, and (ii) based on the position, adjust the speed of the fan from a first speed to a second speed; and
the first speed and the second speed are greater than zero.

11. The integrated circuit of claim 4 , wherein the first control module is configured to adjust the speed of the fan if (i) the fan is rotating, and (ii) the speed of the fan is not equal to the predetermined speed.

12. The integrated circuit of claim 4 , wherein:
the first control module receives the control signal from a host device,
the host device comprises the second control module
the control signal comprises the predetermined speed, and
the host device is separate from the integrated circuit.

13. A computer comprising:
the integrated circuit of claim 12 ;
the host device; and
the fan assembly.

14. The integrated circuit of claim 4 , wherein the first control module is configured (i) drive a second coil of the motor while not driving the first coil, and (ii) determine whether the motor is stuck and the fan is not rotating based on the voltage induced in the first coil of the motor.

15. An integrated circuit for controlling operation of a motor of a fan assembly, wherein the fan assembly comprises a housing, one or more sensors, and a fan, wherein the motor is in the housing, and wherein the motor is configured to rotate the fan, the integrated circuit comprising:
a detection module separate from the fan assembly, wherein the detection module is configured to, independent of signals generated by the one or more sensors, detect (i) a voltage induced in a first coil of the motor, wherein the first coil is an undriven coil; and
a first control module configured to (i) receive a control signal from a second control module, and (ii) control the operation of the motor of the fan assembly to control a speed of the fan based on (a) the control signal, and (b) the voltage induced in the first coil of the motor, wherein the second control module is separate from the integrated circuit,
wherein the first control module is further configured to
determine the speed of the fan and positions of stator poles based on the voltage induced in the first coil of the motor,
compare the speed of the fan to a predetermined speed,
if the speed of the fan is not equal to the predetermined speed, proceed with determining whether the motor is stuck and the fan is not rotating,
wherein the determining of whether the motor is stuck and the fan is not rotating is based on (i) a waveform of a back electromotive force received from the first coil of the motor, and (ii) the positions of stator

Assignees

• Marvell World Trade Ltd

Inventors

• Krishnamoorthy Ravishanker
• Leong Foo Leng
• Susanto Edy
• Zhang Yayue
• Teoh Cheng Yong

Classifications

• H02P6/182

  using back-emf in windings · CPC title

• H02P29/032

  Preventing damage to the motor, e.g. setting individual current limits for different drive conditions · CPC title

• H02K29/12

  using detecting coils {using the machine windings as detecting coil} · CPC title

• F04D27/004 Primary

  by varying driving speed · CPC title

• F04D13/0693

  Details or arrangements of the wiring · CPC title