Method for outputting constant air volume by multi-motor driving system

Patent metadata

Field	Value
Publication number	US-10690371-B2
Application number	US-201816012739-A
Country	US
Kind code	B2
Filing date	Jun 19, 2018
Priority date	Dec 31, 2015
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

A method for outputting constant air volume by a fan system including at least two brushless DC (BLDC) motors, the method including: storing a constant air volume control function Q=F (n, C) in a data processor, where Q indicates an air volume, n indicates a rotational speed of the BLDC motors, and C indicates an operating parameter of the BLDC motors; transmitting, by the data processor, identical speed signal commands to the BLDC motors, and allowing the BLDC motors to operate at equal or approximately equal rotational speeds; and feedbacking, by the BLDC motors, motor operating parameters C to the data processor, calculating, by the data processor, a motor speed n for outputting and maintaining a constant air volume, and transmitting the motor speed to the BLDC motors.

First claim

What is claimed is:

1. A method, comprising:
1) providing a fan system comprising at least two brushless DC (BLDC) motors and a plurality of wind wheels, the at least two brushless DC (BLDC) motors being closed-loop speed-control motors and adapting to drive corresponding wind wheels, and disposing the at least two brushless DC (BLDC) motors and the plurality of wind wheels in one air duct;
2) providing a data processor, and storing a constant air volume control function Q=F (n, C) in the data processor, wherein Q indicates an air volume, n indicates a rotational speed of the at least two BLDC motors, and C indicates an operating parameter of the at least two BLDC motors;
3) transmitting, by the data processor, identical speed signal commands to the at least two BLDC motors, and allowing the at least two BLDC motors to operate at equal or approximately equal rotational speeds; and
4) feedbacking, by the at least two BLDC motors, motor operating parameters to the data processor, calculating, by the data processor, a motor speed n for outputting and maintaining a constant air volume, and transmitting, by the data processor, the motor speed to the at least two BLDC motors.

2. The method of claim 1 , wherein:
the data processor is disposed outside the at least two BLDC motors;
the at least two BLDC motors each comprise a control and drive circuit board and a motor body; The control-and-drive-circuit board comprises a power circuit, a microprocessor, a detection circuit for detecting the motor operating parameters, an inverter circuit, and a rotor position measurement circuit; the power circuit supplies power to circuits;
the rotor position measurement circuit detects and inputs a rotor position signal to the microprocessor;
the detection circuit inputs detected parameters to the microprocessor;
the microprocessor controls the inverter circuit to operate; and
an output terminal of the inverter circuit is connected to windings of a stator assembly.

3. The method of claim 2 , wherein the data processor communicates with the at least two BLDC motors in a wired or wireless mode.

4. The method of claim 3 , wherein two BLDC motors are employed.

5. The method of claim 4 , wherein a difference between a rotational speed specified by the data processor and a real rotational speed of the BLDC motors is within plus or minus 3 turns.

6. The method of claim 2 , wherein the at least two BLDC motors have the same specifications.

7. The method of claim 6 , wherein the control-and-drive-circuit board is integrated with the motor body.

8. The method of claim 2 , wherein the control-and-drive-circuit board is separated from the motor body.

9. The method of claim 8 , wherein control and drive circuit boards of the at least two BLDC motors are integrated with the data processor on one circuit board.

10. The method of claim 9 , wherein the microprocessors of the control-and-drive-circuit boards of the BLDC motors are replaced by the data processor.

11. The method of claim 1 , wherein the data processor is a digital signal processor (DSP) or a microcontroller unit (MCU).

12. The method of claim 1 , wherein the data processor communicates with the at least two BLDC motors in a wired or wireless mode.

13. The method of claim 12 , wherein two BLDC motors are employed.

14. The method of claim 13 , wherein a difference between a rotational speed specified by the data processor and a real rotational speed of the BLDC motors is within plus or minus 3 turns.

15. The method of claim 1 , wherein the motor operating parameters are powers or currents.

16. The method of claim 15 , wherein the constant air volume in the data processor is an external input value.

17. The method of claim 15 , wherein the motor operating parameters fed back to the data processor are the powers, the powers of the BLDC motors are accumulated by the data processor to yield a total power, and then the total power is input to the constant air volume control function Q=F (n, P) to calculate the motor speed n for outputting and maintaining the constant air volume.

18. The method of claim 15 , wherein the motor operating parameters fed back to the data processor are a bus current, the bus currents of the BLDC motors are accumulated by the data processor to yield a total bus current, and then the total bus current is input to the constant air volume control function Q=F (n, P) to calculate the motor speed n for outputting and maintaining the constant air volume.

Assignees

• Zhongshan Broad Ocean Motor Co

Inventors

• Sun Hairong
• Wu Jipeng

Classifications

• H02P5/50

  by comparing electrical values representing the speeds · CPC title

• H02P5/74

  controlling two or more AC dynamo-electric motors (H02P5/46, H02P5/60 take precedence) · CPC title

• H02P2006/045

  Control of current · CPC title

• F24F11/75 Primary

  for maintaining constant air flow rate or air velocity · CPC title

• H02P6/04 Primary

  Arrangements for controlling or regulating the speed or torque of more than one motor (H02P6/10 takes precedence) · CPC title