Motor speed curve control circuit and moter thereof

Patent metadata

Field	Value
Publication number	US-9602036-B2
Application number	US-201514842912-A
Country	US
Kind code	B2
Filing date	Sep 2, 2015
Priority date	Jun 5, 2015
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

The present disclosure illustrates a motor speed curve control circuit. The motor speed curve control circuit is configured for adjusting a speed of a motor according to a motor speed curve. The motor speed curve control circuit comprises a divider resistor module, an analog-to-digital converter and an arithmetic unit. The resistor module is configured for generating at least one turning-point voltage. The turning-point voltage is used to adjust a slope of the motor speed curve. The analog-to-digital converter converts the turning-point voltage to digital form. The arithmetic unit sets a speed associated with the turning-point voltage corresponding to a first preset duty cycle in the motor speed curve, such that the motor speed curve becomes linear. The arithmetic unit generates a second pulse width modulation signal according to the adjusted motor speed curve and a first pulse width modulation signal to drive the motor.

First claim

What is claimed is:

1. A motor speed curve control circuit, the motor speed curve control circuit storing a plurality of motor speed curves for adjusting the speed of a motor according to the motor speed curves, wherein each of the motor speed curves is related to a duty cycle of a first pulse width modulation signal and the speed of the motor, the motor speed curve control circuit comprising:
a divider resistor module, configured to generate at least a turning-point voltage and at least a parameter voltage, wherein each of the motor speed curves has a multi-stage slope;
an analog-to-digital converter, connected to the divider resistor module, and configured to convert the turning-point voltage in a digital form; and
an arithmetic unit, connected to the analog-to-digital converter and a pulse width modulation signal generating unit, and configured to choose one of the motor speed curves according to the parameter voltage and then adjust a slope of the motor speed curve according to the turning-point voltage to make the adjusted motor speed curve become linear;
wherein the arithmetic unit sets the speed corresponding to the turning-point voltage as the speed within a first preset duty cycle of the motor speed curve to make the adjusted motor speed curve become linear, and then the arithmetic unit outputs a second pulse width modulation signal according to the adjusted motor speed curve for driving the motor.

2. The motor speed curve control circuit according to claim 1 , wherein the motor speed curve control circuit is connected to a control unit, and the control unit is configured to control a full-bridge circuit according to the second pulse width modulation signal output by the arithmetic unit for making the motor rotate.

3. The motor speed curve control circuit according to claim 2 , wherein the full-bridge circuit comprises a first switch, a second switch, a third switch and a fourth switch, the first switch and the second switch are connected to an input voltage source, the third switch and the fourth switch are connected to a ground terminal, and the gates of the first switch, the second switch, the third switch and the fourth switch are respectively connected to the control unit, wherein the conducting states of the first switch, the second switch, the third switch and the fourth switch are related to a working state of the motor.

4. The motor speed curve control circuit according to claim 3 , wherein the first switch and the second switch are P-channel MOSFETs, and the third switch and the fourth switch are N-channel MOSFETs.

5. The motor speed curve control circuit according to claim 1 , wherein the parameter voltage comprises a speed voltage and a pulse width voltage, the speed voltage is related to an initial speed of the motor in the motor speed curve, and the pulse width voltage is related to an initial duty cycle of the first pulse width modulation signal in the motor speed curve.

6. The motor speed curve control circuit according to claim 5 , wherein the parameter voltage comprises a threshold voltage, the threshold voltage is related to a minimum driving threshold of the motor in the motor speed curve, and when the duty cycle of the first pulse width modulation signal is lower than the minimum driving threshold, the motor stops working.

7. The motor speed curve control circuit according to claim 1 , wherein the divider resistor module outputs a plurality of turning-point voltages, the arithmetic unit adjusts the slopes of the motor speed curve according to the turning-point voltages to make the adjusted motor speed curve become linear.

8. A motor, comprising:
a motor speed curve control circuit, the motor speed curve control circuit storing a plurality of motor speed curves for adjusting the speed of the motor according to the motor speed curves, wherein each of the motor speed curve is related to a duty cycle of a first pulse width modulation signal and the speed of the motor, the motor speed curve control circuit comprising:
a divider resistor module, configured to generate at least a turning-point voltage and at least a parameter voltage, wherein each of the motor speed curves has a multi-stage slope;
an analog-to-digital converter, connected to the divider resistor module, and configured to convert the turning-point voltage in a digital form;
an arithmetic unit, connected to the analog-to-digital converter and a pulse width modulation signal generating unit, and configured to choose one of the motor speed curves according to the parameter voltage and then adjust a slope of the motor speed curve according to the turning-point voltage to make the adjusted motor speed curve become linear; and
a control unit, connected to the motor speed curve control circuit, configured to control a full-bridge circuit according to a second pulse width modulation signal output by the arithmetic unit for making the motor rotate;
wherein the arithmetic unit sets the speed corresponding to the turning-point voltage as the speed within a first preset duty cycle of the motor speed curve to make the adjusted motor speed curve become linear, and then the arithmetic unit outputs the second pulse width modulation signal according to the adjusted motor speed curve for driving the motor.

9. The motor according to claim 8 , further comprising:
a Hall sensor, connected to the control unit, configured to generate a first timing signal and a second timing signal to the control unit, such that the control unit controls the full-bridge circuit according to the first timing signal, the second timing signal and the second pulse width modulation signal.

10. The motor according to claim 8 , wherein the full-bridge circuit comprises a first switch, a second switch, a third switch and a fourth switch, the first switch and the second switch are connected to an input voltage source, the third switch and the fourth switch are connected to a ground terminal, and the gates of the first switch, the second switch, the third switch and the fourth switch are respectively connected to the control unit, wherein the conducting states of the first switch, the second switch, the third switch and the fourth switch are related to a working state of the motor.

11. The motor according to claim 10 , wherein the first switch and the second switch are P-channel MOSFETs, and the third switch and the fourth switch are N-channel MOSFETs.

12. The motor according to claim 8 , wherein the parameter voltage comprises a speed voltage and a pulse width voltage, the speed voltage is related to an initial speed of the motor in the motor speed curve, and the pulse width voltage is related to an initial duty cycle of the first pulse width modulation signal in the motor speed curve.

13. The motor according to claim 12 , wherein the parameter voltage comprises a threshold, the threshold voltage is relevant to a minimum driving threshold of the motor in the motor speed curve, and when the duty cycle of the first pulse width modulation signal is lower than the minimum driving threshold, the motor stops working.

14. The motor according to claim 8 , wherein the divider resistor module outputs a plurality of turning-point voltages, the arithmetic unit adjusts the slopes of the motor speed curve according to the turning-point voltages for making the adjusted motor speed curve become linear.

Assignees

• Anpec Electronics Corp

Inventors

• Chen Kun-Min
• Li Ching-Sheng
• Chiu I-Lin

Classifications

• H02P6/06

  Arrangements for speed regulation of a single motor wherein the motor speed is measured and compared with a given physical value so as to adjust the motor speed · CPC title

• H02P6/085

  in a bridge configuration · CPC title

• H02P27/08 Primary

  with pulse width modulation · CPC title

• H02P23/0004 Primary

  Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control · CPC title