Apparatus and method for measuring motor speed

Patent metadata

Field	Value
Publication number	US-10175260-B2
Application number	US-201615202163-A
Country	US
Kind code	B2
Filing date	Jul 5, 2016
Priority date	Jul 13, 2015
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

An apparatus for measuring motor speed may include: an encoder configured to output a signal based on revolution of a motor; and a control unit configured to detect a mechanical angle of the motor according to an output signal of the encoder, estimate an actual angle of the motor based on the detected mechanical angle, and calculate the speed of the motor by differentiating the estimated actual angle.

First claim

What is claimed is:

1. An apparatus for measuring motor speed, comprising:
an encoder configured to output a signal based on revolution of a motor;
a control unit configured to detect a mechanical angle of the motor according to an output signal of the encoder, estimate an actual angle of the motor based on the detected mechanical angle, and calculate the speed of the motor by differentiating the estimated actual angle; and
a filter unit configured to low-pass filter the calculated motor speed.

2. The apparatus of claim 1 , wherein when estimating the actual angle, the control unit estimates an angular velocity of the motor, calculates a correction angle based on the estimated angular velocity, and estimates the actual angle based on the calculated correction angle.

3. The apparatus of claim 2 , wherein the control unit estimates the actual angle by adding the correction angle to the mechanical angle.

4. The apparatus of claim 1 , wherein when calculating the speed of the motor, the control unit calculates an angular velocity by differentiating the estimated actual angle, and calculates the speed of the motor by converting the calculated angular velocity into RPM (Revolution Per Minute).

5. A method for measuring motor speed, comprising:
detecting, by a control unit, a mechanical angle of a motor according to an output signal of an encoder;
estimating, by the control unit, an actual angle of the motor based on the detected mechanical angle;
calculating, by the control unit, the speed of the motor by differentiating the estimated actual angle; and
low-pass filtering, by the control unit, the calculated motor speed, after the calculating of the speed of the motor.

6. The method of claim 5 , wherein the estimating of the actual angle comprises:
estimating the angular velocity of the motor;
calculating a correction angle based on the estimated angular velocity; and
estimating the actual angle based on the calculated correction angle.

7. The method of claim 6 , wherein in the estimating of the actual angle based on the calculated correction angle, the control unit estimates the actual angle by adding the correction angle to the mechanical angle.

8. The method of claim 5 , wherein the calculating of the speed of the motor comprises:
calculating an angular velocity by differentiating the estimated actual angle; and
converting the calculated angular velocity into RPM.

9. An apparatus for measuring motor speed, comprising:
an encoder configured to output a signal based on revolution of a motor; and
a control unit configured to detect a mechanical angle of the motor according to an output signal of the encoder, estimate an actual angle of the motor based on the detected mechanical angle, and calculate the speed of the motor by differentiating the estimated actual angle,
wherein when calculating the speed of the motor, the control unit calculates an angular velocity by differentiating the estimated actual angle, and calculates the speed of the motor by converting the calculated angular velocity into revolutions per minute (RPM).

Assignees

• Hyundai Mobis Co Ltd

Inventors

• Lee Jae Hyun

Classifications

• G01D5/24495

  using previous values · CPC title

• G01P3/481 Primary

  of pulse signals · CPC title

• G01P3/66 Primary

  using electric or magnetic means (G01P3/80 takes precedence; measuring short time intervals G04F8/00, G04F10/00) · CPC title