Low frequency bilateral communication over distributed power lines

A full-duplex communications system for transmitting information, comprising:

• an electric power distribution line to transmit an electrical power signal;
• a power distribution circuit coupled to the electric power distribution line to provide the electrical power signal to a power consumer via the electric power distribution line;
• a first information transmitter coupled in series with a neutral connection of the power distribution circuit to provide first information signals concurrently with the electrical power signal to the power consumer via the electric power distribution line;
• at least one protection module coupled between the neutral connection and ground to provide a short-circuit connection between the neutral connection and ground upon recognition of an open-circuit condition at the first information transmitter;
• a first information receiver, coupled to a power consumer device powered by the electrical power signal, to receive the first information signals via the electric power distribution line;
• a second information transmitter coupled to the power consumer device to provide second information signals concurrently with the electrical power signal via the electric power distribution line;
• and
• a second information receiver coupled to the power distribution circuit to receive the second information signals via the electric power distribution line;
• and
• whereby full duplex communication between the power distribution circuit and the power consumer is accomplished via the electric power distribution line.

A signal transmission device for transmitting information signals from a utility power distribution node to a power consumer via a power distribution line used to provide a power signal to the power consumer, the signal transmission device comprising:

• (a) an information signal modulating circuit to superimpose an information signal on the power signal, wherein the information signal has a basebond frequency less than a frequency of the power signal, comprising:
• (i) a zero-crossover sense circuit to determine approximate zero-crossover points of the power signal;
• (ii) a signal inversion circuit coupled to the zero-crossover sense circuit to invert the phase of every nth half-period of the power signal between successive ones of the zero-crossover points to create a carrier power signal, wherein consecutive positive phases of the carrier power signal correspond to a first logic state of the information signal and consecutive negative phases of the carrier power signal correspond to a second logic state of the information signal;
• and
• (b) signal driving circuitry coupled to the signal inversion circuit and to the power distribution line to drive the carrier power signal to the power consumer via the power distribution line.

A full-duplex communications system for transmitting information, comprising:

• an electric power distribution line to transmit an electrical power signal;
• a power distribution circuit coupled to the electric power distribution line to provide the electrical power signal to a power consumer via the electric power distribution line;
• a first information transmitter coupled to the power distribution circuit to provide first information signals concurrently with the electrical power signal to the power consumer via the electric power distribution line;
• a first information receiver, coupled to a power consumer device powered by the electrical power signal, to receive the first information signals via the electric power distribution line;
• a second information transmitter coupled to the power consumer device to provide second information signals concurrently with the electrical power signal via the electric power distribution line;
• and
• a second information receiver coupled to the power distribution circuit to receive the second information signals via the electric power distribution line,
• whereby full duplex communication between the power distribution circuit and the power consumer is accomplished via the electric power distribution line,
• wherein the first and second information transmitters each comprise a sub-carrier signal generator circuit to respectively modulate the first and second information signals onto the electrical power signal wherein each of the sub-carrier signal generator circuits comprise a signal modulator to modulate the corresponding first and second information signals onto the electrical power signal at a frequency lower than a frequency of the electrical power signal.

A full-duplex communications system for disseminating information from a power distribution station to a plurality of power consumer sites via an electric power distribution line which provides power to the plurality of power consumer sites, comprising:

• a power distribution line coupled to each of the plurality of power consumer sites;
• a power distribution circuit coupled to the power distribution line at the power distribution station to provide a power signal to the plurality of power consumer sites via the power distribution line;
• an information transmitter coupled to the power distribution circuit to provide information signals concurrently with the power signal to the plurality of power consumers via the power distribution line;
• at least one information receiver at each of the plurality of power consumer sites, each of the information receivers being coupled to a power consumer device powered by the power signal, wherein each of the information receivers receives the information signals via the power distribution line;
• a consumer information transmitter at each of the power consumer devices to provide consumer information signals concurrently with the power signal to the power distribution station via the power distribution line;
• and
• a consumer information receiver coupled to the power distribution circuit to receive the consumer information signals via the power distribution line,
• whereby full duplex communication between the power distribution circuit and the plurality of power consumer sites is accomplished via the power distribution line,
• wherein the information transmitter and the consumer information transmitter each comprise a sub-carrier signal generator circuit to respectively modulate the information and consumer information signals onto the electrical power signal wherein each of the sub-carrier signal generator circuits comprise a signal modulator to modulate the corresponding first and second information signals onto the electrical power signal at a frequency lower than a frequency of the electrical power signal.

A full-duplex communications system for transmitting information, comprising:

• an electric power distribution line to transmit an electrical power signal;
• a power distribution circuit coupled to the electric power distribution line to provide the electrical power signal to a power consumer via the electric power distribution line;
• a first low frequency signal modulator coupled to the power distribution circuit to modulate first information signals onto the electrical power signal, at a frequency lower than a frequency of the electrical power signal, thereby providing to the power consumer via the electric power distribution line, the first information signals passing through one or more transformers disposed along the power distribution line;
• a first information receiver, coupled to a power consumer device powered by the electrical power signal, to receive the first information signals via the electric power distribution line;
• a second low frequency signal modulator coupled to the power consumer device to modulate second information signals onto the electrical power signal, at a frequency lower than a frequency of the electrical power signal, via the electric power distribution line, the second information signals passing through one or more transformers disposed along the power distribution line;
• and
• a second information receiver coupled to the power distribution circuit to receive the second information signals via the electric power distribution line,
• whereby full duplex communication between the power distribution circuit and the power consumer is accomplished via the electric power distribution line.

A full-duplex communications system for transmitting information, comprising:

• an electric power distribution line to transmit an electrical power signal;
• a power distribution circuit coupled to the electric power distribution line to provide the electrical power signal to a power consumer via the electric power distribution line;
• a first information transmitter coupled in series with a neutral connection of the power distribution circuit to provide first information signals concurrently with the electrical power signal to the power consumer via the electric power distribution line, the first information signals passing through one or more transformers disposed along the power distribution line;
• at least one protection module coupled between the neutral connection and ground to provide a short-circuit connection between the neutral connection and ground upon recognition of an open circuit condition at the first information transmitter;
• a first information receiver, coupled to a power consumer device powered by the electrical power signal, to receive the first information signals via the electric power distribution line;
• a second information transmitter coupled to the power consumer device to provide second information signals concurrently with the electrical power signal via the electric power distribution line, the second information signals passing through one or more transformers disposed along the power distribution line;
• and
• a second information receiver coupled to the power distribution circuit to receive the second information signals via the electric power distribution line,
• whereby full duplex communication between the power distribution circuit and the power consumer is accomplished via the electric power distribution line.