METHOD AND DEIVCE FOR MEASURING CURRENT

• US 20140118013A1
• Filed: 12/06/2013
• Published: 05/01/2014
• Est. Priority Date: 10/31/2012
• Status: Active Grant

• Current Assignee: Huawei Digital Power Technologies Company Limited (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Investment & Holding Co., Ltd.
• Inventors: Yang, Jing, Wei, Qinghuan
• Granted Patent: US 9,482,696 B2
• Time in Patent Office: Days
• US Class Current: 324/691
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01N 27/025 a current being generated within the material by induction
• CPC Class Codes: G01R 1/203 Resistors used for electric measuring, e.g. decade resistors standards, resistors for comparators, series resistors, shunts resistors in general H01C; microwave or radiowave terminations H01P1/26; coupling devices H01R
• CPC Class Codes: G01R 27/08 Measuring resistance by measuring both voltage and current

Abstract

A method and an electronic device are disclosed for measuring a current. The device measures a temperature between a first sampling point and a second sampling point on a metal structure carrying a current to be measured. The device outputs a first signal according to the measured temperature and a second signal after sampling and filtering the first signal. The device detects the first voltage signal at the first sampling point and the second voltage signal at the second sampling point. The device samples and filters a difference between the first voltage signal and the second voltage signal and outputs a third voltage signal. The device restores the second signal to a temperature value representing a temperature between the first sampling point and the second sampling point and calculates a resistance value between the first sampling point and the second sampling point according to the temperature value.

Claims

1. A method, comprising:

measuring, by an electronic device having a metal structure, a temperature between a first sampling point and a second sampling point on the metal structure carrying a current to be measured, and outputting a first signal according to the measured temperature;

outputting, by the electronic device, a second signal after sampling and filtering the first signal;

detecting, by the electronic device, a first voltage signal at the first sampling point and a second voltage signal at the second sampling point, sampling and filtering a signal difference between the first voltage signal and the second voltage signal, and outputting a third voltage signal;

converting, by the electronic device, the second signal into a first digital signal, restoring, according to the first digital signal, the second signal to a temperature value representing the temperature between the first sampling point and the second sampling point, and calculating a resistance value between the first sampling point and the second sampling point according to the temperature value;

converting, by the electronic device, the third voltage signal into a second digital signal, and restoring, according to the second digital signal, the third voltage signal to a voltage value representing a voltage between the first sampling point and the second sampling point; and

calculating, by the electronic device, a value of a current between the first sampling point and the second sampling point according to the voltage value and the resistance value.

2. The method according to claim 1, wherein the calculating a resistance value between the first sampling point and the second sampling point according to the temperature value specifically comprises:

calculating a resistance value corresponding to the temperature value by using a resistance-temperature comparison table or a resistance-temperature formula.

3. The method according to claim 1, wherein the metal structure comprises a copper bar between the first sampling point and the second sampling point, the copper bar comprising multiple holes.

4. An electronic device, comprising:

a metal bar, configured to carry a current to be measured;

a temperature sensor, configured to measure a temperature between a first sampling point and a second sampling point located on the metal structure, and output a first signal according to the measured temperature;

a temperature sampling detector, configured to receive the first signal output by the temperature sensor, and output a second signal after sampling and filtering the first signal;

a voltage sampling detector, configured to detect a first voltage signal at the first sampling point located on the metal structure and a second voltage signal at the second sampling point located on the metal structure, sample and filter a signal difference between the first voltage signal and the second voltage signal, and output a third voltage signal;

an analog-digital converter, configured to;

receive the second signal output by the temperature sampling detector, convert the second signal into a first digital signal, and output the first digital signal; and

receive the third voltage signal output by the voltage sampling detector, convert the third voltage signal into a second digital signal, and output the second digital signal; and

a controller, configured to;

receive the first digital signal and the second digital signal output by the analog-digital converter, restore, according to the first digital signal, the second signal to a temperature value representing the temperature between the first sampling point and the second sampling point, and calculate a resistance value between the first sampling point and the second sampling point according to the temperature value; and

restore the third voltage signal to a voltage value representing a voltage between the first sampling point and the second sampling point according to the second digital signal, and calculate, according to the voltage value and the resistance value, a value of a current between the first sampling point and the second sampling point.

5. The electronic device according to claim 4, wherein the controller is specifically configured to:

calculate the resistance value between the first sampling point and the second sampling point and corresponding to the temperature value by using a resistance-temperature comparison table or a resistance-temperature formula.

6. The device according to claim 4, wherein the analog-digital converter is integrated inside the controller;

or the analog-digital converter is integrated outside the controller.

7. The device according to claim 4, wherein the metal structure comprises a copper bar comprising.

8. The device according to claim 4, wherein the metal structure comprises a copper bar comprising multiple apertures.