Intelligent electronic device with enhanced power quality monitoring and communication capabilities

• US 20100324845A1
• Filed: 04/03/2008
• Published: 12/23/2010
• Est. Priority Date: 01/27/2005
• Status: Active Grant

• Current Assignee: EI Electronics LLC (Hubbell, Inc.)
• Original Assignee: Electro Industries/Gaugetech
• Inventors: Wang, Wei, Kagan, Erran, Spanier, Joseph
• Granted Patent: US 8,160,824 B2
• Time in Patent Office: Days
• US Class Current: 702/62
• CPC Class Codes: G01R 13/00 Arrangements for displaying electric variables or waveforms
• CPC Class Codes: G01R 19/00 Arrangements for measuring currents or voltages or for indicating presence or sign thereof G01R5/00 takes precedence; for measuring bioelectric currents or voltages A61B5/24
• CPC Class Codes: G01R 19/2513 Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging
• CPC Class Codes: G01R 21/133 by using digital technique
• CPC Class Codes: G01R 22/10 using digital techniques
• CPC Class Codes: G06F 17/40 Data acquisition and logging for input to computer G06F3/00
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

An intelligent electronic device (IED) has enhanced power quality and communications capabilities. The power meter can perform energy analysis by waveform capture, detect transient on the front end voltage input channels and provide revenue measurements. The power meter splits and distributes the front end input channels into separate circuits for scaling and processing by dedicated processors for specific applications by the power meter. Front end voltage input channels are split and distributed into separate circuits for transient detection, waveform capture analysis and revenue measurement, respectively. Front end current channels are split and distributed into separate circuits for waveform capture analysis and revenue measurement, respectively.

Claims

1. An intelligent electronic device (IED) for recording at least one waveform of an AC power system, the IED comprising:

a voltage input circuit operative to sense line voltage from the AC power system and generate at least one voltage signal representative of the voltage sensed from the AC power system;

at least one analog-to-digital converter circuit configured to sample the at least one voltage signal to output digital samples representative of said voltage input circuit;

at least one processor operatively coupled to said analog-to-digital converter and configured to perform at least one mathematical computation on samples received from the analog-to-digital converter; and

at least one volatile memory operatively coupled to said at least one processor to receive samples from the analog-to-digital converter;

wherein the at least one processor is configured to trigger a recording and storing in non-volatile memory at least one of said digital samples based on an algorithm that includes at least one of an adaptive trigger, a waveshape trigger and a rate of change trigger.

2. The IED of claim 1, further comprising a communication device for sending an alarm, limit, or measured data via Ethernet protocol.

3. The IED of claim 2, wherein the communication device sends said data utilizing SNMP protocol.

4. The IED of claim 1, wherein said adaptive trigger utilizes a voltage averaging scheme.

5. The IED of claim 1, wherein the at least one processor performs an adaptive trigger and waveshape trigger.

6. The IED of claim 3, wherein the communication device sends at least one alarm via e-mail.

7. An intelligent electronic device (IED) for recording at least one waveform of an AC power system, the IED comprising:

a voltage input circuit operative to sense line voltage from the AC power system and generate at least one voltage signal representative of the voltage sensed from the AC power system;

at least one analog-to-digital converter circuit configured to sample the at least one voltage signal to output digital samples representative of said voltage input circuit;

at least one processor operatively coupled to said analog-to-digital converter and configured to perform at least one mathematical computation on samples received from the analog-to-digital converter; and

at least one volatile memory operatively coupled to said at least one processor to receive samples from the analog-to-digital converter;

wherein the at least one processor is configured to trigger a recording and storing in non-volatile memory at least one of said digital samples based on an algorithm that includes at least one of an adaptive trigger wherein the adaptive trigger includes adjusting at least one trigger set point based on the preceding average voltage sensed.

8. The IED of claim 7, further comprising a communication device for sending an alarm, limit, or measured data via Ethernet protocol.

9. The IED of claim 8, wherein the communication device sends said data utilizing SNMP protocol.

10. The IED of claim 7, wherein the at least one processor performs an adaptive trigger and waveshape trigger.

11. The IED of claim 7, further comprising a graphic display for displaying waveform records.

12. The IED of claim 7, further comprising a graphic display for displaying waveform records with a time stamp.

13. The IED of claim 11, wherein the graphic display displays status input changes.

14. The IED of claim 11, further comprising means for producing audible sounds.

15. The IED of claim 7, further comprising at least one anti-aliasing filter for filtering sensed voltage above a predetermined set point.

16. A system for an intelligent electronic device (IED) to send data utilizing Simple Network Management Protocol (SNMP) and Modbus TCP, the system comprising:

an SNMP agent;

SNMP management software;

a software system which communicates via Modbus TCP protocol; and

the intelligent electronic device (IED) comprising;

an Ethernet communication port located on the IED including at least one of a physical port and a wireless port; and

a Modbus TCP protocol stack, wherein the IED can parse Modbus TCP requests coming from the software system.

17. The system of claim 16, wherein the Ethernet communication port is an RJ45 port.

18. The system of claim 16, further comprising a wireless network and an antenna.

19. The system of claim 16, wherein the communication port is configured for transmitting an e-mail alarm while communicating via Modbus TCP protocol and SNMP to at least one software system.

20. The system of claim 19, wherein the e-mail alarm includes transient voltage event data.

21. The system of claim 19, wherein data transmitted to said software system includes waveform records.

23. The system of claim 16, wherein the IED further comprises:

a voltage input circuit operative to sense line voltage from the AC power system and generate at least one voltage signal representative of the voltage sensed from the AC power system;

at least one analog-to-digital converter circuit configured to sample the at least one voltage signal to output digital samples representative of said voltage input circuit;

at least one processor operatively coupled to said analog-to-digital converter and configured to perform at least one mathematical computation on samples received from the analog-to-digital converter; and

at least one volatile memory operatively coupled to said at least one processor to receive samples from the analog-to-digital converter;

24. The system of claim 23, wherein the IED includes at least one anti-aliasing filter for filtering sensed voltage above a predetermined set point.

22. The system of claim 22, wherein the waveform records are captured using at least one of said adaptive, waveshape and rate of change triggers.

25. An intelligent electronic device (IED) including an anti-aliased waveform recording system, the waveform recording system comprising:

a voltage input circuit operative to sense line voltage from the AC power system and generate at least one voltage signal representative of the voltage sensed from the AC power system;

at least one analog-to-digital converter circuit configured to sample the at least one voltage signal to output digital samples representative of said voltage input circuit;

at least one of a digital and analog anti-alias filter for filtering the samples above a predetermined set point;

at least one processor operatively coupled to said analog-to-digital converter and configured to perform at least one mathematical computation on samples received from the analog-to-digital converter; and

at least one volatile memory operatively coupled to said at least one processor to receive samples from the analog-to-digital converter.

26. The IED of claim 25, further comprising an Ethernet port to communicate data on said waveform information.

27. The IED of claim 25, wherein said Ethernet protocol is at least one of Modbus TCP and SNMP protocols.

28. The IED of claim 25, wherein the processor records waveforms on based on at least one adaptive, envelope and rate of change trigger.