Method and apparatus to commission voltage sensors and branch circuit current sensors for branch circuit monitoring systems

Patent metadata

Field	Value
Publication number	US-9829519-B2
Application number	US-201514722481-A
Country	US
Kind code	B2
Filing date	May 27, 2015
Priority date	May 27, 2015
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A system and method for a branch current monitoring system employing a 2-Phase Wye, a Single-Phase 3-Wire or a Single-Phase 2-Wire wiring configuration that is configured to identify a phase association and a polarity for a branch circuit current sensor using the phase angle between voltage and current. Also, a system and method for verifying phase association and polarity determinations for branch circuit current sensors that utilizes real and reactive power measurements.

First claim

What is claimed is:

1. A method for a branch current monitoring system employing a 2-Phase Wye wiring configuration, wherein the branch current monitoring system has a first phase and a second phase, the method comprising:
obtaining a voltage measurement using a voltage sensor associated with the first phase;
obtaining a current measurement using a branch circuit current sensor, wherein the branch circuit current sensor is intended to measure a phase current of the first phase;
determining a phase angle between the voltage measurement and the current measurement; and
using the phase angle and a set of rules including a plurality of predetermined rules to identify at least one phase association and at least one polarity for the branch circuit current sensor, wherein the using the phase angle and the set of rules comprises:
determining that the branch circuit current sensor is one of: (i) associated with the first phase with a normal polarity or (ii) associated with the second phase with a flipped polarity in response to the phase angle satisfying a first one of the rules; or
determining that the branch circuit current sensor is one of: (i) associated with the first phase with a flipped polarity or (ii) associated with the second phase with a normal polarity in response to the phase angle satisfying a second one of the rules, wherein the first one of the rules comprises the phase angle being within a first range or a second range and the second one of the rules comprises the phase angle being within a third range, and wherein the first range is greater than or equal to 0° and less than 20°, wherein the second range is greater than 320° and less than 360°, and wherein the third range is greater than 140° and less than 200°.

2. A method for a branch current monitoring system employing a 2-Phase Wye wiring configuration, wherein the branch current monitoring system has a first phase and a second phase, the method comprising:
obtaining a voltage measurement using a voltage sensor associated with the first phase;
obtaining a current measurement using a branch circuit current sensor, wherein the branch circuit current sensor is intended to measure a phase current of the first phase;
determining a phase angle between the voltage measurement and the current measurement; and
using the phase angle and a set of rules including a plurality of predetermined rules to identify at least one phase association and at least one polarity for the branch circuit current sensor, wherein the using the phase angle and the set of rules comprises:
determining that the branch circuit current sensor is one of: (i) associated with the first phase with a normal polarity or (ii) associated with the second phase with a flipped polarity in response to the phase angle satisfying a first one of the rules; or
determining that the branch circuit current sensor is one of: (i) associated with the first phase with a flipped polarity or (ii) associated with the second phase with a normal polarity in response to the phase angle satisfying a second one of the rules, wherein the first one of the rules comprises the phase angle being within a first range and the second one of the rules comprises the phase angle being within a second range, and wherein the first range is greater than 20° and less than 80°, and wherein the second range is greater than 200° and less than 260°.

3. A method for a branch current monitoring system employing a Single-Phase 3-Wire wiring configuration, wherein the branch current monitoring system has a first phase and a second phase, the method comprising:
obtaining a voltage measurement using a voltage sensor associated with the first phase;
obtaining a current measurement using a branch circuit current sensor, wherein the branch circuit current sensor is intended to measure a phase current of the first phase;
determining a phase angle between the voltage measurement and the current measurement; and
using the phase angle and a set of rules including a plurality of predetermined rules to identify at least one phase association and at least one polarity for the branch circuit current sensor, wherein the using the phase angle and the set of rules comprises:
determining that the branch circuit current sensor is one of: (i) associated with the first phase with a normal polarity or (ii) associated with the second phase with a flipped polarity in response to the phase angle satisfying a first one of the rules; or
determining that the branch circuit current sensor is one of: (i) associated with the first phase with a flipped polarity or (ii) associated with the second phase with a normal polarity in response to the phase angle satisfying a second one of the rules, wherein the first one of the rules comprises the phase angle being within a first range or a second range and the second one of the rules comprises the phase angle being within a third range, and wherein the first range is greater than or equal to 0° and less than 50°, wherein the second range is greater than 350° and less than 360°, and wherein the third range is greater than 170° and less than 230°.

4. A method for a branch current monitoring system employing a Single-Phase 2-Wire wiring configuration, wherein the branch current monitoring system has a first phase, the method comprising:
obtaining a voltage measurement using a voltage sensor associated with the first phase;
obtaining a current measurement using a branch circuit current sensor, wherein the branch circuit current sensor is intended to measure a phase current of the first phase;
determining a phase angle between the voltage measurement and the current measurement; and
using the phase angle and a set of rules including a plurality of predetermined rules to identify at least one phase association and at least one polarity for the branch circuit current sensor, wherein the using the phase angle and the set of rules comprises:
determining that the branch circuit current sensor is associated with the first phase with a normal polarity in response to the phase angle satisfying a first one of the rules, wherein the first one of the rules comprises the phase angle being within a first range, and wherein the first range is greater than or equal to 0° and less than 50°; or
determining that the branch circuit current sensor is associated with the first phase with a flipped polarity in response to the phase angle satisfying a second one of the rules, wherein the second one of the rules comprises the phase angle being within a second range, and wherein the second range is greater than or equal to 170° and less than 230°.

5. A branch circuit meter module for a branch current monitoring system employing a 2-Phase Wye wiring configuration, wherein the branch current monitoring system has a first phase and a second phase, the branch circuit meter module comprising:
a control system, wherein the control system stores and is structured to execute a number of routines, the number of routines being structured to:
receive a voltage measurement from a voltage sensor associated with the first phase;
receive a current measurement from a branch circuit current sensor, wherein the branch circuit current sensor is intended to measure a phase current of the first phase;
determine a phase angle between the voltage measurement and the current measurement; and
use the phase angle and a set of rules including a plurality of predetermined rules to identify at least one phase association and at least one polarity for the branch circuit current sensor, wherein the routines are structured to use the phase angle and the set of rules by:

determining that the branch circuit current sensor is one of: (i) associated with the first phase with a normal polarity or (ii) associated with the second phase with a flipped polarity in response to

Assignees

• Eaton Corp

Inventors

• Hayashi Alan Kenji
• Zaremski Brian Zachary
• Gao Zhi

Classifications

• G01R31/67

  Testing the correctness of wire connections in electric apparatus or circuits · CPC title

• G01R21/133

  by using digital technique · CPC title

• G01R31/2829

  Testing of circuits in sensor or actuator systems (testing of apparatus for measuring electric or magnetic variables G01R35/00; testing of indicating or recording apparatus G01D; in airbag systems B60R21/0173; checking gas analysers G01N33/007; monitoring or fail-safe circuits for electromagnets H01F7/1844) · CPC title

• G01R25/00 Primary

  Arrangements for measuring phase angle between a voltage and a current or between voltages or currents · CPC title

• G01R35/005 Primary

  Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references (G01R33/0035, G01R35/002 take precedence) · CPC title