Detecting the open or closed state of a circuit breaker

Patent metadata

Field	Value
Publication number	US-12591009-B2
Application number	US-202217991607-A
Country	US
Kind code	B2
Filing date	Nov 21, 2022
Priority date	Nov 22, 2021
Publication date	Mar 31, 2026
Grant date	Mar 31, 2026

Abstract

A meter including a phase conductor connected to a phase line of the network, a cut-off member, and a detection circuit comprising: an injection chain arranged, while the cut-off member is open, to generate a test signal with a predetermined voltage level, and arranged to inject the test signal into the phase conductor downstream from the cut-off member; a measurement chain arranged to measure an intermediate voltage level of the test signal at a measurement point of the injection chain, which point is situated between the generator component and the injection component; a processor component arranged to act as a function of the intermediate voltage level in order to determine whether the circuit breaker is open or closed.

First claim

The invention claimed is:

1 . A meter arranged to measure electrical energy delivered to an installation by a distribution network comprising a phase line and a neutral line, the meter being arranged to be connected to a circuit breaker situated outside the meter and downstream therefrom, the meter comprising:
a phase conductor and a neutral conductor arranged to be connected respectively to the phase line and to the neutral line of the distribution network; a cut-off member connected in the phase conductor; a detection circuit comprising:
an injection chain comprising at least one generator component and an injection component, the at least one generator component being arranged, while the cut-off member is open, to generate a test signal with a predetermined voltage level, the injection component being arranged to inject the test signal into the phase conductor downstream from the cut-off member, the injection component having a first terminal connected to the at least one generator component and a second terminal connected to the phase conductor;
a measurement chain arranged to measure an intermediate voltage level of the test signal at a measurement point (Pm) of the injection chain, which point is situated between the at least one generator component and the injection component and is connected to the at least one generator component and to the first terminal of the injection component;
a processor component arranged to act as a function of the intermediate voltage level in order to determine whether the circuit breaker is open or closed.

2 . The meter according to claim 1 , wherein the injection component is a first capacitor that is integrated in a first highpass filter serving to filter out interfering signals coming from the distribution network.

3 . The meter according to claim 1 , wherein the at least one generator component comprises both a generator module arranged to produce the test signal with the predetermined voltage level and also a driver forming a current source arranged to ensure that the test signal is generated with a current level that is sufficient for conserving a voltage level at the output of the at least one generator component that is equal to the predetermined voltage level.

4 . The meter according to claim 1 , wherein the measurement chain comprises in succession, from upstream to downstream, a second highpass filter, an envelope detector, and a lowpass filter.

5 . The meter according to claim 4 , further comprising an analog-to-digital converter positioned upstream from the envelope detector.

6 . The meter according to claim 4 , further comprising an analog-to-digital converter positioned downstream from the envelope detector.

7 . The meter according to claim 1 , wherein the injection chain is arranged, while the cut-off member is open, to inject the test signal periodically for a predetermined duration.

8 . The meter according to claim 1 , wherein the injection chain is arranged, while the cut-off member is open, to inject the test signal continuously.

9 . The meter according to claim 1 , wherein the test signal is an alternating signal at a frequency that is at least one hundred times greater than the frequency of the phase current flowing in the phase line of the distribution network.

10 . The meter according to claim 1 , wherein the meter is a single-phase meter.

11 . The meter according to claim 10 , wherein the phase conductor is connected to electrical ground of the meter upstream from the cut-off member, the meter further comprising a second capacitor positioned upstream from the cut-off member and having a first terminal connected to the neutral conductor and a second terminal connected to the phase conductor.

12 . The meter according to claim 11 , wherein the injection component is a first capacitor, the injection chain comprising a resistor connected between the first capacitor and an output of the at least one generator component, the processor component being arranged to compare the intermediate voltage level of the test signal with a predetermined detection threshold, and to detect that the circuit breaker is open when the intermediate voltage level of the test signal is greater than the predetermined threshold and that the circuit breaker is closed when the intermediate voltage level of the test signal is less than or equal to the predetermined detection threshold, the predetermined detection threshold lying between a high level and a low level Vb such that:
Vb=Vp *( Z ( C 1)+ Z (subscriber)+ Z ( C 2)∥ Z (upstream))/( R+Z ( C 1)+ Z (subscriber)+ Z ( C 2)∥ Z (upstream)) where:
Vp is the predetermined voltage level, Z(C1) is the impedance of the first capacitor, Z(C2) is the impedance of the second capacitor, Z(upstream) is the impedance between the phase line and the neutral line upstream from the meter, and Z(subscriber) is the impedance between the phase line and the neutral line downstream from the meter, said impedances being estimated at the frequency of the test signal.

13 . The meter according to claim 1 , wherein the meter is a three-phase meter.

14 . The meter according to claim 13 , wherein the injection component is a first capacitor, the injection chain including a resistor connected between the first capacitor and an output of the at least one generator component, the processor component being arranged to compare the intermediate voltage level of the test signal with a predetermined detection threshold, and to detect that the circuit breaker is open when the intermediate voltage level of the test signal is greater than the predetermined threshold and that the circuit breaker is closed when the intermediate voltage level of the test signal is less than or equal to the predetermined detection threshold, the predetermined detection threshold lying between a high level and a low level Vb such that:
Vb=Vp *( Z ( C 1)+ Z (subscriber))/( R+Z ( C 1)+ Z (subscriber)) where: Vp is the predetermined voltage level of the test signal, Z(C1) is the impedance of the first capacitor, and Z(subscriber) is the impedance between the phase line and the neutral line downstream from the meter, said impedances being estimated at the frequency of the test signal.

15 . A detection method performed in the processor component of the meter according to claim 1 , the method comprising the following steps performed while the cut-off member is open:
using the injection chain to generate and inject the test signal into the phase conductor downstream from the cut-off member; acquiring the intermediate voltage level of the test signal; as a function of the intermediate voltage level of the test signal, determining whether the circuit breaker is open or closed.

16 . A non-transitory computer-readable storage medium storing a computer program including instructions that cause the processor component of the meter according to claim 1 to execute a detection method performed in the processor component of the meter, the method comprising the following steps performed while the cut-off member is open:
using the injection chain to generate and inject the test signal into the phase conductor downstream from the cut-off member;
acquiring the intermediate voltage level of the test signal;
as a function of the intermediate voltage level of the test signal, determining whether the circuit breaker is open or closed.

Assignees

• Sagemcom Energy & Telecom Sas

Inventors

• Teboulle Henri
• Lhuillier Pierre

Classifications

• G01R31/3275

  Fault detection or status indication · CPC title

• G01R19/0084

  Measuring voltage only · CPC title

• G01R31/3274 Primary

  Details related to measuring, e.g. sensing, displaying or computing; Measuring of variables related to the contact pieces, e.g. wear, position or resistance (measuring contact resistance G01R27/205) · CPC title

• G01R22/068 Primary

  Arrangements for indicating or signaling faults · CPC title

• G01R31/327 Primary

  Testing of circuit interrupters, switches or circuit-breakers · CPC title