Powerline carrier control installation

• US 4,383,243 A
• Filed: 05/18/1979
• Issued: 05/10/1983
• Est. Priority Date: 06/08/1978
• Status: Expired due to Term

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Tappeiner, Hermann, Smutny, Kurt, Krugel, Karl-Heinz, Paessler, Ernst-Robert
• Primary Examiner(s): Groody, James J.
• Application Number:
  US06/040,477
• Time in Patent Office: 1,453 Days
• Field of Search: 340/310 R, 340/310 A, 340/310 CP, 333/23 C, 455/91, 455/114, 455/127, 455/282, 455/352
• US Class Current: 307/3
• CPC Class Codes: H02J 13/00009 using pulsed signals
• CPC Class Codes: H04B 2203/545 Audio/video application, e.g. interphone
• CPC Class Codes: H04B 2203/5483 using coupling circuits
• CPC Class Codes: H04B 2203/5491 using filtering and bypassing
• CPC Class Codes: H04B 3/56 Circuits for coupling, blocking, or by-passing of signals
• 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 powerline carrier control installation includes a control transmitter with an audio frequency output voltage, an isolation transformer, a coupling capacitor for parallel coupling to an a-c voltage network, and a device for suppressing a line frequency backward voltage. For coupling the audio frequency output voltage to the a-c voltage network, a resonant circuit tuned to the audio frequency is provided, the resonant circuit capacitance being supplied by the coupling capacitor and the resonant circuit inductance formed essentially by the main field inductance of the isolation transformer, eliminating the need for a separate coupling choke.

A device, specifically the powerline carrier control transmitter itself, is equipped to deliver, in addition to the audio frequency output voltage, a line frequency compensating a-c voltage which has a low amplitude in comparison to the line a-c voltage in order to suppress the line frequency feedback transmitted from the network.

Claims

1. A powerline carrier control installation comprising:

(a) a powerline carrier control transmitter which supplies an audio frequency output voltage;

(b) an isolation transformer having a main field inductance and having a transformation ratio higher than 1;

5 fed on the primary, low voltage side by the audio frequency output voltage;

(c) a coupling capacitor coupling the secondary side of said transformer to an a-c voltage network of given distribution system feeder a-c voltage and line frequency, the line frequency being somewhat lower than the audio frequency of the output voltage;

(d) said coupling capacitor along with the main field inductance of the isolating transformer forming a tuned resonant circuit the resonant frequency of which is at least approximately tuned to the audio frequency; and

(e) said powerline carrier control transmitter acting as a device for suppressing the line frequency backward voltage transmitted from the network side, the control transmitter being equipped to deliver, in addition to the audio frequency output voltage, a line frequency compensating a-c voltage which is low in amplitude in comparison to the line a-c voltage.

3. A powerline carrier control installation according to claim 1, wherein said powerline carrier control transmitter is coupled to the primary winding of the isolation transformer through only an additional inductance.

4. A powerline carrier control installation according to claim 1, wherein the powerline carrier control transmitter is coupled to the primary winding of the isolation transformer at most through only an additional inductance, and wherein the main field inductance of the isolation transformer, the capacitance of the coupling capacitor, and said additional inductance are rated so that for audio frequency the inductive impedance of the circuit including of these components equals the capacitive impedance.

2. A powerline carrier control installation comprising:

(a) a powerline carrier control transmitter which supplies an audio frequency output voltage;

(b) an isolation transformer having a main field inductance and having a transformation ratio higher than 1;

5 fed on the primary, low voltage side by the audio frequency output voltage;

(c) a coupling capacitor only, coupling the secondary side of said transformer directly to an a-c voltage network of given distribution system feeder a-c voltage and line frequency, the line frequency being somewhat lower than audio frequency of the output voltage;

(d) an additional inductance only, coupling the powerline carrier control transmitter to the primary winding of the isolation transformer;

(e) said coupling capacitor along with the main field inductance of the isolating transformer and additional inductance forming a tuned resonant circuit the resonant frequency of which is at least approximately tuned to the audio frequency, the resonant frequency of said tuned resonant circuit being determined by the capacitance of the coupling capacitor, the main field inductance of the isolation transformer and the additional inductance transmitted to the secondary winding of the transformer; and

(f) the powerline carrier control transmitter being equipped to take up a line frequency backward voltage which is low in amplitude in comparison to the line a-c voltage and itself acting as a device for suppressing a line frequency feedback transmitted from the network side.

5. A powerline carrier control installation according to claim 3 or 2, wherein said additional inductance is formed by an additional choke connected in series with the primary winding of the isolation transformer.

6. A powerline carrier control installation according to claim 5, wherein said additional choke is structurally included in the isolating transformer.

7. A powerline carrier control installation according to claim 3 or 2, wherein said additional inductance is formed by a non-negligible leakage inductance of the isolation transformer.