Embedded high frequency ground monitor

Patent metadata

Field	Value
Publication number	US-11353485-B2
Application number	US-202016787278-A
Country	US
Kind code	B2
Filing date	Feb 11, 2020
Priority date	Feb 11, 2020
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

A measurement module receives a defined system topology and system component characteristics information for a system. The measurement module calculates an expected system impedance for the defined system topology. The measurement module collects one or more impedance measurements using a high frequency voltage stimulus. Finally, the measurement module compares the one or more impedance measurements with the expected system impedance to determine adequacy of protective grounding of the system.

First claim

What is claimed is:

1. A measurement module for high frequency ground monitoring, comprising:
at least one processor;
at least one non-transitory memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, performs an operation comprising:
receiving a defined system topology of a system and information on characteristics of components in the system;
calculating an expected system impedance for the system;
conducting one or more measurements of actual system impedance of the system using a high frequency voltage stimulus; and
comparing the one or more measurements of actual system impedance with the expected system impedance to determine adequacy of protective grounding of the system.

2. The measurement module of claim 1 , further comprising:
a high frequency signal generator in the measurement module, configured to provide the high frequency voltage stimulus by injecting a high frequency test signal into the components connected through grounding capacitance to a reference ground of the system;
a high frequency current measurement circuit in the measurement module, configured to measure actual return current collectively from the components through the grounding capacitance, in response to the test signal, to obtain the one or more measurements of the actual system impedance of the system;
the at least one memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, further performs an operation comprising:
determining whether the actual system impedance substantially equals the expected system impedance; and
characterizing the adequacy of protective grounding of the system based on the determination.

3. The measurement module of claim 2 , further comprising:
the at least one memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, further performs an operation comprising:
determining that the actual system impedance substantially equals the expected system impedance; and
characterizing the adequacy of protective grounding of the system as acceptable, based on the determination.

4. The measurement module of claim 2 , further comprising:
the at least one memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, further performs an operation comprising:
determining that the actual system impedance does not substantially equal the expected system impedance; and
characterizing the adequacy of protective grounding of the system as not acceptable, based on the determination.

5. The measurement module of claim 4 , further comprising:
the at least one memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, further performs an operation comprising:
outputting an indication that the grounding capacitance of the components does not have a good connection to the reference ground of the system.

6. The measurement module of claim 2 , further comprising:
a control bus connecting the measurement module to one or more of the components in the system;
the at least one memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, further performs an operation comprising:
measuring an actual return current from one or more components selected with a control signal on the control bus, through the grounding capacitance, in response to the test signal, to obtain one or more measurements of an actual component impedance of the one or more selected components.

7. The measurement module of claim 2 , further comprising:
a data bus connecting the measurement module to one or more of the components in the system;
the at least one memory including computer program code, wherein the computer program code, when executed by operation of the at least one processor, further performs an operation comprising:
monitoring with the data bus, indications of data errors generated by one or more of the components;
determining a failure of capacitive grounding of the one or more components that is generating the data error indications.

8. The measurement module of claim 1 , wherein the conducting of one or more measurements of actual system impedance and the comparing of the one or more measurements of actual system impedance with the expected system impedance, is performed either on a frequent schedule, on demand, or in response to detected error conditions in the system.

9. A method for high frequency ground monitoring, comprising:
receiving a defined system topology of a system and information on characteristics of components in the system;
calculating an expected system impedance for the system;
conducting one or more measurements of actual system impedance of the system using a high frequency voltage stimulus; and
comparing the one or more measurements of actual system impedance with the expected system impedance to determine adequacy of protective grounding of the system.

10. The method of claim 9 , further comprising:
providing a high frequency voltage stimulus by injecting a high frequency test signal into the components connected through grounding capacitance to a reference ground of the system;
measuring actual return current collectively from the components through the grounding capacitance, in response to the test signal, to obtain the one or more measurements of the actual system impedance of the system;
determining whether the actual system impedance substantially equals the expected system impedance; and
characterizing the adequacy of protective grounding of the system based on the determination.

11. The method of claim 10 , further comprising:
determining that the actual system impedance substantially equals the expected system impedance; and
characterizing the adequacy of protective grounding of the system as acceptable, based on the determination.

12. The method of claim 10 , further comprising:
determining that the actual system impedance does not substantially equal the expected system impedance; and
characterizing the adequacy of protective grounding of the system as not acceptable, based on the determination.

13. The method of claim 12 , further comprising:
outputting an indication that the grounding capacitance of the components does not have a good connection to the reference ground of the system.

14. The method of claim 10 , further comprising:
selecting with a control signal on a control bus, one or more of the components in the system to be connected to the high frequency signal generator, to provide the high frequency test signal to the selected one or more components;
measuring an actual return current from the one or more selected components through the grounding capacitance, in response to the test signal, to obtain one or more measurements of an actual component impedance of the one or more selected components.

15. The method of claim 10 , further comprising:
monitoring with a data bus, indications of data errors generated by one or more of the components;
determining a failure of capacitive grounding of the one or more components that is generating the data error indications.

16. The method of claim 9 , wherein the conducting of one or more measurements of actual system impedance and the comparing of the one or more measurements of actual system impedance with the expected system impedance, is performed

Assignees

• Schneider Electric Usa Inc

Inventors

• Jefferies Kevin M
• White Matthew L
• Edwards Benjamin W
• Weiler Richard K
• Freeman Alan E

Classifications

• G01R27/205

  Measuring contact resistance of connections, e.g. of earth connections · CPC title

• G01R29/105

  using anechoic chambers; Chambers or open field sites used therefor (test sites used for measuring on other objects than aerials G01R29/0828; wave absorbing devices H01Q17/00) · CPC title

• G01R29/0821

  rooms and test sites therefor, e.g. anechoic chambers, open field sites or TEM cells (for testing antennas G01R29/105) · CPC title

• G01R31/58

  Testing of lines, cables or conductors (testing of electric windings G01R31/72) · CPC title

• G01R31/002

  where the device under test is an electronic circuit · CPC title