Electronic device and control method of fan speed thereof

1 . An electronic device, comprising:

a storage array, comprising a plurality of storage units;

a row fan, comprising at least one fan and configured to cool the storage array; and

a controller, configured to receive a distance signal corresponding to a distance between the storage array and the row fan, and determines a distance threshold for each of the storage units;

wherein when the distance is longer than the distance threshold, the controller is configured to output a control signal to the row fan to increase a rotation speed of the row fan;

wherein determining the distance threshold for each of the storage units comprises:

changing the distance between each of the storage units and the row fan, and recording a decibel level of noise measured at a position of each of the storage units corresponding to different distances; and

selecting a minimum distance corresponding to the noise that is under a predetermined decibel level as the distance threshold for each of the storage units;

wherein the predetermined decibel level is defined according to a working efficiency of each storage unit under influences of the noise emitted by the row fan.

2 . The electronic device as claimed in claim 1 , wherein the controller is configured to read an identification of each of the storage units and to set the distance threshold of each of the storage units according to the identification.

3 . The electronic device as claimed in claim 2 , wherein the controller comprises:

a storage controller, configured to read the identification of each of the storage units and to generate an identification signal associated with the identification of each of the storage units.

4 . The electronic device as claimed in claim 3 , wherein the controller further comprises a platform management controller configured to determine whether the distance is longer than the distance threshold, and when the distance is longer than the distance threshold, the platform management controller is configured to output the control signal to the row fan to increase the rotation speed of the row fan.

5 . The electronic device as claimed in claim 4 ,

wherein the platform management controller is configured to connect to the Internet and read the distance threshold of each of the storage units from a database according to the identification signal;

wherein the database is configured to store a table to record the identification of each of the storage units and the distance threshold corresponding to each of the storage units.

6 . The electronic device as claimed in claim 1 , further comprising a relative motion sensor and a distance sensor; wherein the relative motion sensor is configured to detect a relative motion of the storage array from a preset position with the row fan and to output a corresponding enable signal; wherein the distance sensor is configured to sense the distance between the memory array and the row fan according to the enable signal and output a corresponding distance signal.

7 . The electronic device as claimed in claim 6 , wherein the relative motion sensor is a far-infrared sensor.

8 . The electronic device as claimed in claim 7 , further comprising a drawer structure; wherein the row fan is disposed on a backplane, and the backplane faces a first plane of the drawer structure; the distance sensor is disposed on the backplane or the first plane of the drawer structure.

9 . The electronic device as claimed in claim 8 , further comprising a casing, wherein the drawer structure is disposed in the casing and is able to perform the relative motion with the casing in one direction.

10 . The electronic device as claimed in claim 9 , wherein the storage array is disposed in the drawer structure and the row fan is disposed on the casing.

11 . The electronic device as claimed in claim 1 , wherein when the distance is longer than the longest one of the distance thresholds of the storage units, the controller is configured to output the control signal to the row fan to increase the rotation speed of the row fan.

12 . The electronic device as claimed in claim 1 , wherein the distance threshold for each of the storage units is determined according to a level of the noise emitted by the row fan measured at the position of each of the storage units.

13 . A control method of a rotation speed of a fan, suitable for an electronic device having a storage array, a row fan, a distance sensor, a relative motion sensor, and a controller, wherein the storage array comprises a plurality of storage units, the control method comprising:

the distance sensor senses a distance between the storage array and the row fan and outputs a corresponding distance signal;

the controller determines a distance threshold for each of the storage units; and

when the controller determines that the distance exceeds the distance threshold according to the distance signal, the controller outputs a control signal to the row fan to increase the rotation speed of the row fan;

wherein determining the distance threshold for each of the storage units comprises:

changing the distance between each of the storage units and the row fan, and recording a decibel level of noise measured at a position of each of the storage units corresponding to different distances; and

selecting a minimum distance corresponding to the noise that is under a predetermined decibel level as the distance threshold for each of the storage units;

wherein the predetermined decibel level is defined according to a working efficiency of each storage unit under influences of the noise emitted by the row fan.

14 . The control method as claimed in claim 13 , further comprising:

the relative motion sensor detects the relative motion of the storage array from a preset position with the row fan and outputs a corresponding enable signal; and

the distance sensor senses the distance between the storage array and the row fan according to the enable signal.

15 . The control method as claimed in claim 13 , wherein the step of determining whether the distance exceeds the distance threshold and outputting the control signal to the row fan comprises:

in response to the controller determining that the distance is longer than the longest one of the distance thresholds of the storage units according to the distance signal, the controller outputs the control signal to the row fan to increase the rotation speed of the row fan.

16 . The control method as claimed in claim 13 , further comprises a step of setting the distance threshold for each of the storage units comprising:

the controller reads the identification of each of the storage units and generates an identification signal associated with the identification of each of the storage units; and

the controller sets the distance threshold for each of the storage units according to the identification.

17 . The control method as claimed in claim 16 , wherein the step of setting the distance threshold for each of the storage units further comprises:

reading the distance threshold for each of the storage units from a database according to the identification signal.

18 . The control method as claimed in claim 17 , wherein the database comprises a table; the table records the identification of each of the storage units and the distance threshold corresponding to each of the storage units.

19 . The control method as claimed in claim 17 , further comprising:

determining the distance threshold for each of the storage units according to a level of the noise emitted by the row fan measured at the position of each of the storage units; and

storing the distance threshold for each of the storage units in the database.