Multi-fan assembly control

1. A fan assembly, comprising:

a first fan;

a second fan; and

a controller configured to:

determine that an air movement demand corresponds to operation of at least one of the first fan and the second fan at a resonance speed;

instruct the first fan to operate at a first speed which is less than the resonance speed; and

instruct the second fan to operate at a second speed which is greater than the resonance speed.

2. The fan assembly of claim 1 , wherein the first fan and the second fan are configured to operate in parallel.

3. The fan assembly of claim 1 , wherein the controller is configured to instruct the first fan to operate at the first speed which is less than the resonance speed by a first amount, wherein the controller is configured to instruct the second fan to operate at the second speed which is greater than the resonance speed by a second amount, and wherein the first amount is approximately equal to the second amount.

4. The fan assembly of claim 1 , comprising a third fan.

5. The fan assembly of claim 4 , wherein the controller is configured to instruct the third fan to operate at a third speed which is greater than the resonance speed.

6. The fan assembly of claim 5 , wherein the controller is configured to instruct the first fan to operate at the first speed which is less than the resonance speed by a first amount, wherein the controller is configured to instruct the second fan to operate at the second speed which is greater than the resonance speed by a second amount, wherein the controller is configured to instruct the third fan to operate at the third speed which is greater than the resonance speed by a third amount, and wherein the first amount is approximately equal to a combination of the second amount and the third amount.

7. The fan assembly of claim 4 , wherein the controller is configured to instruct the third fan to operate at a third speed which is less than the resonance speed.

8. The fan assembly of claim 7 , wherein the controller is configured to instruct the first fan to operate at the first speed which is less than the resonance speed by a first amount, wherein the controller is configured to instruct the second fan to operate at the second speed which is greater than the resonance speed by a second amount, wherein the controller is configured to instruct the third fan to operate at the third speed which is less than the resonance speed by a third amount, and wherein a combination of the first amount and the third amount is approximately equal to the second amount.

9. The fan assembly of claim 1 , comprising one or more vibration sensors communicatively coupled with the controller, wherein the one or more vibration sensors are configured to detect vibrations in the first fan, the second fan, or both, wherein the controller is configured to receive data indicative of the vibrations in the first fan, the second fan, or both from the one or more vibration sensors, and wherein the controller is configured to analyze the data indicative of the vibrations to determine that the air movement demand corresponds to operation of the first fan and the second fan at the resonance speed.

10. The fan assembly of claim 1 , comprising one or more air sensors communicatively coupled with the controller, wherein the one or more air sensors are configured to detect an airflow parameter indicative of a flow rate of air through the first fan, the second fan, or both, and wherein the controller is configured to receive data indicative of the airflow parameter from the one or more air sensors.

11. The fan assembly of claim 10 , wherein the controller is configured to:

analyze the data indicative of the airflow parameter to determine the desired movement of air; or

analyze the data indicative of the airflow parameter to determine that the flow rate corresponds to the desired movement of air.

12. A fan assembly controller comprising processing circuitry configured to:

determine a demand for air movement by a fan assembly;

determine that the demand for air movement corresponds to operation of at least one of a first fan of the fan assembly and a second fan of the fan assembly at a resonance speed;

instruct the first fan to operate at a first speed which is less than the resonance speed; and

instruct the second fan to operate at a second speed which is greater than the resonance speed.

13. The fan assembly controller of claim 12 , wherein determining the demand for air movement by the fan assembly comprises receiving the demand for air movement by the fan assembly.

14. The fan assembly controller of claim 12 , wherein the processing circuitry is configured to operate the first fan and the second fan in parallel.

15. The fan assembly controller of claim 12 , wherein the processing circuitry is configured to:

instruct the first fan to operate at the first speed which is less than the resonance speed by a first amount; and

instruct the second fan to operate at the second speed which is greater than the resonance speed by a second amount, wherein the first amount is approximately equal to the second amount.

16. The fan assembly controller of claim 12 , wherein the processing circuitry is configured to:

receive data indicative of vibrations in the first fan, the second fan, or both; and

analyze the data indicative of the vibrations to determine that the vibrations exceed a threshold vibration amount indicative of the first fan and the second fan operating at the resonance speed.

17. The fan assembly controller of claim 12 , wherein the processing circuitry is configured to:

receive data indicative of an operating flow rate of the fan assembly; and

determine that the operating flow rate corresponds to the demand for air movement, wherein the demand for air movement comprises a target flow rate of the fan assembly.

18. The fan assembly controller of claim 12 , wherein the processing circuitry is configured to:

receive data indicative of an operating flow rate of the fan assembly; and

analyze the data indicative of the operating flow rate to determine the demand for air movement.

19. A fan controller comprising a memory having a non-transitory, computer-readable medium including one or more sequences of instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising:

determining that an air movement demand corresponds to operation of at least one of a first fan of the fan assembly and a second fan of the fan assembly at a resonance speed;

instructing the first fan to operate at a first speed which is less than the resonance speed; and

instructing the second fan to operate at a second speed which is greater than the resonance speed.

20. The fan controller of claim 19 , wherein the operations comprise:

instructing the first fan to operate at the first speed which is less than the resonance speed by a first amount; and

instructing the second fan to operate at the second speed which is greater than the resonance speed by a second amount, wherein the first amount is approximately equal to the second amount.

21. The fan controller of claim 19 , wherein the determining operation comprises:

instructing the first fan, the second fan, or both to operate at the resonance speed based on the air movement demand;

receiving, from one or more vibration sensors, data indicative of vibrations of the first fan, the second fan, or both; and

analyzing the data indicative of the vibrations to determine that the vibrations exceed a threshold vibration amount indicative of the first fan and the second fan operating at the resonance speed.

22. The fan controller of claim 19 , wherein the operations comprise:

receiving, at the controller and from one or more air sensors, data indicative of a flow rate of air through the first fan, the second fan, or both; and

analyzing the data indicative of the flow rate of air to determine the air movement demand.

23. The fan controller of claim 19 , wherein the operations comprise:

receiving, at the controller and from one or more air sensors, data indicative of a flow rate of air through the first fan, the second fan, or both; and

analyzing the data indicative of the flow rate of air to determine that an operating movement of air corresponds to the air movement demand.

24. The fan controller of claim 19 , wherein the operations comprise operating the first fan and the second fan in parallel.