Distribution network powerline carrier communication system

• US 3,942,170 A
• Filed: 01/31/1975
• Issued: 03/02/1976
• Est. Priority Date: 01/31/1975
• Status: Expired due to Term

• Current Assignee: ABB Power T&D Limited (ABB Limited)
• Original Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Inventors: Whyte, Ian A.
• Primary Examiner(s): Habecker, Thomas B.
• Application Number:
  US05/546,068
• Time in Patent Office: 396 Days
• Field of Search: 340/310 A, 340/310 R, 340/151
• US Class Current: 340/12.38
• CPC Class Codes: H02J 13/00007 using the power network as support for the transmission
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H04B 2203/5416 by adding signals to the wave form of the power source
• CPC Class Codes: H04B 2203/5425 improving S/N by matching impedance, noise reduction, gain control
• CPC Class Codes: H04B 2203/5433 Remote metering
• CPC Class Codes: H04B 2203/5437 Wired telephone
• CPC Class Codes: H04B 2203/5441 Wireless systems or telephone
• CPC Class Codes: H04B 2203/5479 using repeaters
• CPC Class Codes: H04B 2203/5483 using coupling circuits
• CPC Class Codes: H04B 2203/5487 cables
• CPC Class Codes: H04B 3/542 the information being in digital form
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 40/121 using the power network as support for the transmission

Abstract

A distribution powerline carrier communication system for providing distribution automation functions. The communication system includes a distribution powerline, with inductive couplers and frequency translating repeaters cooperating to circumvent signal obstructions, such as distribution transformers, and to increase the signal strength. The inductive couplers pick up the communication signals without metallic contact to the primary distribution lines, and the repeaters change the frequency band of the communication signals, enabling the amplifier gain of the repeaters to be selected without limitation due to undesirable feedback and oscillation.

Claims

1. A powerline communication system, comprising:

frequency translating repeater means,

uniquely addressable remote communication terminals,

means providing an interrogation signal in a first frequency band which includes an address of a selected remote communication terminal,

a first communication link including powerline conductors and magnetic field coupler means interconnecting said means which provides said interrogation signal and said repeater means,

a second communication link including powerline conductors interconnecting each repeater means with certain of said remote communication terminals,

each of said repeater means including means for changing the frequency of said interrogation signal to a second frequency band which is non-overlapping with said first frequency band, and means for applying the resulting interrogation signal to its associated second communication link,

each of said remote communication terminals, when uniquely addressed by an interrogation signal over its associated second communication link, providing a response signal on said second communication link, with said response signal being in a third frequency band which is non-overlapping with the first and second frequency bands,

and response receiving means associated with said first communication link for receiving the response signal provided by an addressed remote communication terminal.

2. The powerline communication system of claim 1 including a utility meter associated with each remote communication terminal, and encoder means for translating the reading of said utility meter to a signal which is incorporated into the response signal provided by the remote communication terminal when it is uniquely addressed by an interrogation signal.

3. The powerline communication system of claim 1 wherein the responding remote communication terminal adds its unique address to the response signal.

4. The powerline communication system of claim 1 including a distribution transformer associated with each frequency translating means, with each distribution transformer interconnecting a powerline conductor of the first communication link with a powerline conductor of a second communication link.

5. The powerline communication system of claim 4 wherein each frequency translating repeater means receives the interrogation signal from the first communication link and applies the modified interrogation signal to a second communication link, by-passing the associated distribution transformer.

6. A powerline communication system, comprising:

first powerline conductor means,

second powerline conductor means,

distribution transformer means interconnecting said first and second powerline conductor means,

electrical loads connected to said second powerline conductor means,

frequency translating repeater means associated with certain of said distribution transformer means,

uniquely addressable remote communication terminals associated with certain of said electrical loads,

a source of interrogation signals which provides an interrogation signal in a first frequency band having an address of a selected remote communication terminal,

response receiving means,

means providing an interrogation communication link between said source of interrogation signals and said remote communication terminals, including said primary electrical distribution powerline conductor means, magnetic field coupling means coupling said first powerline conductor means to said repeater means, coupling means coupling said repeater means to said second powerline conductor means, and means coupling each remote communication terminal to said second powerline conductor means, whereby said repeater means changes the frequency band of the interrogation signal applied to the second powerline conductor means to a second band which is non-overlapping with the first band,

means providing a response communication link between said remote communication terminal and said response receiving means, including said second powerline conductor means, said distribution transformer means, said first powerline conductor means, and means coupling said response receiving means to said first powerline conductor means, whereby each remote communication terminal provides a response signal for said response receiving means when it is addressed by an interrogation signal with said response signal being in a third frequency band, which is non-overlapping with said first and second frequency bands.

7. The powerline communication system of claim 6 including a utility meter associated with each remote communication terminal, and encoder means for translating the reading of said utility meter to a signal which is incorporated in the response signal provided by the remote communication terminal when it is uniquely addressed by the interrogation signal.

8. The powerline communication system of claim 6 wherein the responding remote communication terminal adds its unique address to the response signal.

9. A powerline communication system for transmitting carrier signals over first and second distribution network powerline conductor means connected between a distribution network substation and a plurality of distribution transformers, and between the distribution transformers and a plurality of electrical loads, respectively, comprising:

frequency translating repeater means at certain of the distribution transformers,

first and second coupling means coupling each of said repeater means to the first and second powerline conductor means, respectively, connected to the associated distribution transformer, with said first coupling means being a magnetic field coupler,

uniquely addressable remote communication terminals at certain of the electrical loads,

means coupling each of said remote communication terminals to the second powerline conductor means connected to the associated electrical load,

means providing an interrogation signal which includes an address for addressing a selected remote communication terminal,

a central communication terminal at the substation providing a first modulated carrier signal on the first powerline conductor means responsive to said interrogation signal, which is in a first frequency band,

said repeater means each including means for receiving said first modulated carrier signal, and for transmitting a second modulated carrier signal responsive to said modified interrogation signal over the second powerline conductor means it is coupled to, which is in a second frequency band, non-overlapping with said first frequency band,

said remote communication terminals each including means for receiving and processing the second modulated carrier signal, and when uniquely addressed by the second modulated carrier signal providing a response signal on the associated second powerline conductor means which is in a third frequency band, non-overlapping with said first and second frequency bands,

and coupling means coupled to the first powerline conductor means for receiving the response signal.

10. The powerline communication system of claim 9 including a utility meter associated with each remote communication terminal, and encoder means for translating the reading of said utility meter to a signal which is incorporated into the response signal provided by the remote communication terminal when it is uniquely addressed by the second modulated carrier signal.

11. A distribution network powerline carrier communication system for automatically and remotely reading a utility meter, comprising:

a distribution substation,

a plurality of distribution transformers,

a plurality of electrical loads,

first powerline conductors interconnecting said distribution substation with said plurality of distribution transformers,

second powerline conductors interconnecting each of said distribution transformers with certain of said electrical loads,

utility meter means associated with certain of said electrical loads,

encoder means for coverting the reading of said utility meter means to an electrical signal,

frequency translating repeater means associated with certain of said distribution transformers,

addressable remote communication terminal means associated with certain of said electrical loads, for providing a response signal when addressed which includes the signal from an associated encoder means,

a central communication terminal including means for providing an interrogation signal in a first frequency band which includes the address of a selected remote terminal means, and means for receiving signals from said remote communication terminal means,

means providing an interrogation communication link, including said first powerline conductors, a magnetic field coupler coupling said first powerline conductors to said repeater, means coupling said repeater to said second powerline conductors, and means coupling said second powerline conductors to said remote communication terminal means,

said repeater means, when receiving an interrogation signal, providing a modified interrogation signal for its associated remote communication terminals which is in a second frequency band, non-overlapping with said first frequency band,

said remote communication terminal, when uniquely addressed by the modified interrogation signal providing a response signal which includes a signal provided by its associated encoder means, with said response signal being in a third frequency band, non-overlapping with said first and second frequency bands,

and means providing a response communication link which extends from each remote communication terminal means to the central communication terminal, via its associated distribution transformer means.

12. A powerline communication system, comprising:

first and second powerline conductor means,

impedance means associated with said first and second powerline conductor means,

first communication terminal means providing a first communication signal on said first powerline conductor means which has a carrier frequency within a first frequency band,

repeater means,

first coupling means, said first coupling means inductively coupling the first communication signal from said first powerline conductor means into said repeater means,

said repeater means including means for modifying said first communication signal by changing the carrier frequency such that it is within a second frequency band, which is non-overlapping with said first frequency band,

second coupling means applying the modified first communication signal to said second conductor means,

and second communication terminal means associated with said conductor means for receiving the modified first communication signal.

13. The powerline communication system of claim 12 wherein the repeater means includes means for amplifying the modified first communication signal.

14. The powerline communication system of claim 12 wherein the second communication terminal means includes means providing a second communication signal and means for applying said second communication signal to the second powerline conductor means, said second communication signal having a carrier frequency within a third frequency band which is non-overlapping with the first and second frequency bands, and the first communication terminal means includes means for receiving the second communication signal over the first and second conductors.

15. The powerline communication system of claim 12 wherein the impedance means is a transformer which interconnects the first and second powerline conductors, with the repeater means providing a unidirectional by-pass circuit about said transformer for communication signals.

16. The powerline communication system of claim 15 wherein the second communication terminal means includes means providing a second communication signal and means for applying it to the second powerline conductor means, said second communication signal having a carrier frequency within a third frequency band which is non-overlapping with the first and second frequency bands, and the first communication terminal means includes means for receiving the second communication signal.

17. The powerline communication system of claim 12 wherein the first coupling means is a magnetic field coupler including a ferrite rod antenna disposed in the magnetic field adjacent the first conductor means, a band pass filter tuned to the first frequency band, and an amplifier.