US3778726A - Method of and apparatus for generating signals - Google Patents

Method of and apparatus for generating signals Download PDF

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Publication number
US3778726A
US3778726A US00259199A US3778726DA US3778726A US 3778726 A US3778726 A US 3778726A US 00259199 A US00259199 A US 00259199A US 3778726D A US3778726D A US 3778726DA US 3778726 A US3778726 A US 3778726A
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United States
Prior art keywords
frequency
supply system
power supply
mains
output
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Expired - Lifetime
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US00259199A
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English (en)
Inventor
J Kucera
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Zellweger Uster AG
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Zellweger Uster AG
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
    • H02J13/00006—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment
    • H02J13/00007—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment using the power network as support for the transmission
    • H02J13/00009—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment using the power network as support for the transmission using pulsed signals
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S40/00—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them
    • Y04S40/12—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
    • Y04S40/121—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment using the power network as support for the transmission

Definitions

  • a tank [56] References Cited circuit connected to the power supply system and UNITED STATES PATENTS tuned at least approximately to the said repetition fre- 3 182 265 5/ 965 w 328,223 X quency is excited by it into oscillation in each cycle of l u th l 3,446,947 5/1969 Overstreet 328/39 X e Imp Se sequence 3,721,904 3/1973 Verhoeven 328/39 10 Claims, 5 Drawing Figures u H 1 10 P 4 ffl i 16 19% 2% l %4 1 U 1 I l l i ,r- I i N 3 50.
  • the present invention relates to a new and improved method of and apparatus for generating signals, and this invention also relates to application of this method of the transmission of information.
  • alternating current impulses preferably of audio frequency
  • alternating current impulses delivered by a transmitter are superimposed upon a power supply system at a central location by means of coupling elements.
  • These alternating current impulses disseminate throughout the power supply system and, as required, can be removed therefrom at any point with known means and evaluated for example for remote-control purposes.
  • ripple control the required direction of propagation of the aforementioned signals coincides with the direction of energy flow in the power supply system.
  • the power supply system for transmitting signals in the opposite direction to energy flow.
  • ripple control it is standard practice to use only one central transmitter and a large number of receivers
  • the second case is concerned in particular with the transmission of signals by means of a plurality of transmitters from a number of outside stations of the power supply system to a central station with only one or with only a few receivers.
  • Transmitters of this type generate not only a discrete frequency, but also a relatively densely occupied spectrum of oscillations. In practical application, this makes it difficult or even impossible to simultaneously use other discrete frequencies in the same power supply system. This is a serious disadvantage, especially in cases where data emanating from numerous sources has to be transmitted.
  • a further object of the present invention is to provide a method and an apparatus for generating signals where essentially only a selected frequency is transmitted which bears a fixed relationship to the mains frequency.
  • a relatively high noise level can be expected in the transmission channel.
  • the interfering voltages are largely harmonics of the mains frequency f Accordingly, considerable importance is attached to selecting the optimum signal frequency
  • the signals spread out in a direction opposite to the direction of energy flow in the power supply system and that the transmitting power is several times lower than in conventional ripple-control technology.
  • receivers suitable for the present purpose also have to exhibit high sensitivity because only weak signals are received.
  • an apparatus for generating, in a power supply system, a transmission signal with a frequency f bearing a fixed relationship to the mains frequency f of the power supply system comprising an impulse generator, to the input of which a mains frequency control signal source is connected, the impulse generator including a frequency multiplier and a frequency divider in series with a pulse shaper, a controllable switching element the input of which is connected to the impulse generator output, and an oscillating or tank circuit connected to the power supply system and tuned at least approximately to the frequency f the tank circuit being coupled to a circuit controlled by the switching element.
  • FIG. I is a simplified circuit diagram of a first embodiment of transmitter designed according to the teachings of the present invention.
  • FIG. 2 is a circuit diagram of a second embodiment of transmitter according to the present invention.
  • FIG. 3 is a circuit diagram of a third embodiment of transmitter according to the present invention.
  • FIG. 4 is a diagram depicting voltage characteristics of an impulse generator of the third inventive embodiment of transmitter.
  • FIG. 5 is a detailed circuit diagram of a fourth embodiment of transmitter designed according to the present invention.
  • transmitters described by way of example in the following are substantially free from the disadvantage of generating a wide spectrum of undesirable interfering frequencies. They are all based on the fact that energy is delivered by impulses to an oscillating or tank circuit tuned at least approximately to the frequency f at least once during each cycle of the required frequency f preferably for about one-quarter of a cycle.
  • FIG. I is a simplified circuit diagram of a first embodiment of transmitter.
  • An LC-oscillating or tank circuit I with an impedance coil 2 and a capacitor 3 is connected to a phase conductor P and to the neutral conductor of a power supply system with the mains voltage U and the frequency f,
  • the LC-oscillating circuit I is closed through the impedance of the power supply system. Accordingly, any oscillating current generated in the LC-oscillating circuit 1 flows substantially through the phase conductor p to the feed of supply point and from there back through the neutral con ductor O.
  • a controllable switching element is coupled to the LC-oscillating circuit 1 through a winding 4 coupled to the coil 2.
  • a switching transistor 5a serves as the controllable switching element 5.
  • other known eontrollable switching elernnts particularly from the semiconductor art, such as for example thyristors and the like, may also be used for this purpose.
  • the emitter 6 of the switching transistor 5a is connected through a lead 7 to a terminal 8.
  • the collector 9 of the switching transistor 50 is connected through the coupling winding 4 and through a resistor 10 to a terminal 11.
  • a supply voltage U is applied between the terminals 8 and II.
  • the supply voltage U can be generated for example in known manner by a known type of supply device connected to the phase conductor P and the neutral conductor 0.
  • the impulse generator 15 is connected to the terminals 11 and 8 through leads l6 and 17, respectively.
  • One input 18 of the impulse generator 15 is connected through a lead 19 to the phase conductor P.
  • the impulse generator 15 generates impulses whose repetition frequency is consistent with the signal frequency f to be generated.
  • the controllable switching element 5 is controlled by these impulses. Current impulses flow through the coupling winding 4 in the supply circuit of the switching element 5 at the rhythm of the frequency f with the result that the LC-oscillating or tank circuit I is excited into forced oscillations with the frequency f
  • the impulse frequency f,- generated by the impulse generator 15 is kept in a fixed relationship to the mains frequency f,,, by a mains frequency signal delivered through the lead I9 to the impulse generator 15 in a manner that will be described further on.
  • the impulses given off from the impulse generator 15 and the current impulses flowing through the coupling winding 4 preferably have an impulse pause ratio of approximately 1 3.
  • an oscillation of substantially constant amplitude and frequency is generated therein in contrast to other known pulse-excited transmitters which generate damped cycles.
  • a second type of transmitter will now be described by way of example with reference to FIG. 2 with particular emphasis upon the structure and mode of operation of the impulse generator 15.
  • Identical components carry the same reference numerals as employed in FIGS. 1 and 2.
  • the impulse generator 15 contains a frequency multiplier 20.
  • a suitable frequency multi plier 20 is an oscillator synchronised in known manner to a harmonic of the mains frequency f
  • the input 18 of the impulse generator 15 is connected to input 21 of the frequency multiplier 20.
  • An output 22 of the frequency multiplier 20 is connected to an input 23 of a frequency divider 24.
  • An output 25 of the frequency divider 24 is connected to the input 26 of a pulse shaper 27 whose output 28 is connected to the output 14 of the impulse generator 15.
  • the output 14 of the impulse generator 15 is connected to the input of the controllable switching element 5.
  • the frequency multiplier can be adjusted to a factor (n) of II and the frequency divider 24 to a quotient (p) 2 for this case.
  • the signal frequency f is thus always equal to 5.5 times the mains frequency f,,,, even in the event of fluctuations in the mains frequency.
  • other fixed ratios between the signal frequency f and the mains frequency f can be adjusted by altering the aforementioned factor or quotient.
  • a third emboidment of transmitter shown by way of example in FIGS. 3 and 4 illustrates how an impulse sequence with the aforementioned impulse pause ratio of l 3 can be readily generatedat the output 14 of the impulse generator 15, even in the event of fluctuating frequency.
  • identical components carry the same reference numerals.
  • Both the frequency multiplier 20 and also the frequency divider 24 are constructed in known manner in such a way that their output signals U and U respectively, follow a rectangular pattern as a function of time as shown in FIG. 4 in graphs a and b.
  • the output signal U (cf. FIG. 4, graph a) of the frequency multiplier 20 is delivered through a lead 29 to a first input 30 of an AND-gate 31, and the output voltage U (cf. FIG. 4, graph b) of the frequency divider 24 through a lead 32 to a second input 33 of this AND-gate 31, the output voltage U at the output 34 of the AND-gate 31 follows a time pattern of the type shown in graph 0, FIG. 4.
  • the output signal U Since the output signal U already has the required frequency f the impulses of the output voltage U also occur with the repetition frequency f
  • the output signal U receives the required impulse pause ratio of l 3, even where the mains frequency f and hence the frequency f is subjected to fluctuations.
  • the output voltage U of the AND-gate 31 is delivered through a lead 35 to the output 14 of the impulse generator 15 and through the lead 13 to the input 12 of the controllable switching element 5.
  • FIG. 5 identical components also carry the same reference numerals as in FIGS. 1, 2 and 3.
  • a mainsfrequency control signal is delivered through the lead 19 from the phase conductor P to the input'l8 of the impulse generator 15 by way of resistor 36.
  • This control signal is delivered through the resistor 36 to the base terminal 37 of a transistor 38.
  • a diode 39 is connected between the base terminal 37 and the lead 7 which is at zero potential. This diode 39 limits the negative voltage occurring at the base of the transistor 38.
  • the transistor 38 is driven to be fully conductive by the positive half waves of the mains frequency control signal in such a way that output signals of opposite phase occur at its emitter terminal 40 through an emitter resistance 41 and at its collector terminal 42 through a collector resistance 43.
  • These output voltages have a substantially rectangular waveshape or pattern. Accordingly, corresponding flanks in the two output signals are always directed opposite to one another.
  • the output signals occurring at the transistor 38 are differentiated through an RC-section or circuit embodying a capacitor 44 and a resistor 45 and through another RC-section with a capacitor 46 and a resistor 47. These differentiated output signals are delivered in known manner as control signal to a conventional multivibrator 52 from the circuit terminal or junction 48 or 49 through a diode 50 or 51 respectively.
  • the sweep frequency of the multivibrator 52 is synchronised, which moreover is dimensioned in such a way that it oscillates at n-times the mains frequency f
  • the factor n of the frequency multiplier 52 and the quotient of the frequency divider are best selected in such a way that a signal frequency f, which no longer coincides with a harmonic of the mains frequency f is generated. This is the case where n/p does not amount to a whole number.
  • the frequency divider 24 (cf. FIG. 3) is in the form of commercially available module SN 7472, a product of Texas Instrument Corporation, USA.
  • the output signal U of the frequency multiplier 20 (in this case realized by the multivibrator 52) and the output signal U of the frequency divider 24 (module SN 7472) are in a logical configuration.
  • the diodes 53 and 54 and 55 connected to the terminal 11 through a resistor 56 are used for this purpose.
  • the diode 55 is further connected through a resistor 57 to the output 14 of the impulse generator 15 which, in addition, is connected to the lead 7 via a resistor 58.
  • This logical configuration circuit also acts as a pulse shaper as previously considered.
  • a transmitter according to the invention can be obtained with very little outlay, especially where integrated circuits are used.
  • the need for the rigid ratio between the signal frequency f abd the mains frequency f which has to be satisfied at the transmitting end is ideally fulfilled.
  • the need for consistency between the receiver response frequency and the signal frequency f governed by the mains frequency f can be fulfilled with simple means, as already mentioned.
  • the present invention is used with particular advantage for example where it is desired to report the position of switching element in a power distributing system to a central station by transmitting signals through the power supply system. It is possible with a transmitting power of only a few watts to reliably cover distances of for example 10 kilometers and more.
  • a method of generating in a power supply system a transmission signal for remote control purposes with a frequency bearing a fixed relationship to the mains frequency of the power supply system comprising the steps of forming by frequency multiplication and frequency division an impulse sequence whose repetition frequency bears said fixed relationship to the mains frequency. and exciting into oscillation by means of the repetition frequency during each cycle of the impulse sequence a tank circuit connected to the power of supply system and tuned at least approximately to the rep etition frequency, said tank circuit only being excited into forced oscillation in the presence of the repetition frequency.
  • An apparatus for generating in a power supply system a transmission signal for remote control purposes with a frequency bearing a fixed relationship to the mains frequency of the power supply system comprising an impulse generator having an input and an output, a mains frequency control signal source connected with the input of said impulse generator, said impulse generator including a frequency multiplier and a frequency divider in series with a pulse shaper, a controllable switching element having an input connected with the output of said impulse generator, and a tank circuit connected to the power supply system and tuned at least approximately to the transmission signal frequency, said tank circuit being coupled with a circuit controlled by the controllable switching element and delivering the generated oscillating current into the power supply system 7.
  • said frequency multiplier embodies an oscillator synchro nized to a harmonic of the mains frequency.
  • the oscillator comprises a multivibrator synchronized by a mains frequency control signal to a harmonic of the mains frequency.
US00259199A 1971-07-01 1972-06-02 Method of and apparatus for generating signals Expired - Lifetime US3778726A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH891371A CH540607A (de) 1971-07-01 1971-07-01 Verfahren und Vorrichtung zur Signalerzeugung und Anwendung des Verfahrens

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US3778726A true US3778726A (en) 1973-12-11

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US (1) US3778726A (xx)
JP (2) JPS4817658A (xx)
AT (1) AT313417B (xx)
AU (1) AU465762B2 (xx)
BE (1) BE782384A (xx)
CA (1) CA961118A (xx)
CH (1) CH540607A (xx)
DE (1) DE2228008C3 (xx)
FR (1) FR2144209A5 (xx)
GB (1) GB1353128A (xx)
IT (1) IT959983B (xx)
NL (1) NL7202492A (xx)
SE (1) SE391423B (xx)
ZA (1) ZA724133B (xx)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6188258B1 (en) * 1998-11-27 2001-02-13 Mitsubishi Electric System Lsi Design Corporation Clock generating circuitry
US20120197553A1 (en) * 2009-09-29 2012-08-02 Abb Technology Ag Pressure transmitter for measuring the pressure of a process fluid and related method

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AR204804A1 (es) * 1975-02-20 1976-02-27 Gen Public Utilities Aparato para efectuar transmisiones por lineas de energia electrica
DE3581150D1 (de) * 1984-08-27 1991-02-07 Zellweger Uster Ag Verfahren zum senden von daten ueber die leitung eines wechselstrom-verteilungsnetzes und sender zur durchfuehrung des verfahrens.
DE69943227D1 (de) 1998-09-09 2011-04-07 Rohm & Haas Ein Verfahren zur Herstellung einer Kernschalen-schlagmodifizierten Emulsion
US8105149B2 (en) 2006-11-10 2012-01-31 Igt Gaming system and method providing venue wide simultaneous player participation based bonus game

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2772359A (en) * 1955-05-26 1956-11-27 Sperry Rand Corp Synchronized oscillator
US2852671A (en) * 1957-01-23 1958-09-16 Cohen David Method and apparatus for frequency division
US3182265A (en) * 1960-03-02 1965-05-04 Singer Co Frequency discriminator employing a timing circuit
US3343094A (en) * 1963-08-20 1967-09-19 Int Standard Electric Corp Carrier frequency generators
US3349184A (en) * 1965-05-17 1967-10-24 Harvey L Morgan Bandwidth compression and expansion by frequency division and multiplication
US3439278A (en) * 1967-01-24 1969-04-15 Bell Telephone Labor Inc Counter circuit for providing a square-wave output
US3446947A (en) * 1965-11-30 1969-05-27 Bell Telephone Labor Inc Pulse train repetition rate divider that divides by a fractional number
US3617902A (en) * 1970-08-04 1971-11-02 Gen Electric Frequency multiplier
US3721904A (en) * 1970-03-07 1973-03-20 Philips Corp Frequency divider

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH422954A (de) * 1965-05-24 1966-10-31 Landis & Gyr Ag Rundsteueranlage

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2772359A (en) * 1955-05-26 1956-11-27 Sperry Rand Corp Synchronized oscillator
US2852671A (en) * 1957-01-23 1958-09-16 Cohen David Method and apparatus for frequency division
US3182265A (en) * 1960-03-02 1965-05-04 Singer Co Frequency discriminator employing a timing circuit
US3343094A (en) * 1963-08-20 1967-09-19 Int Standard Electric Corp Carrier frequency generators
US3349184A (en) * 1965-05-17 1967-10-24 Harvey L Morgan Bandwidth compression and expansion by frequency division and multiplication
US3446947A (en) * 1965-11-30 1969-05-27 Bell Telephone Labor Inc Pulse train repetition rate divider that divides by a fractional number
US3439278A (en) * 1967-01-24 1969-04-15 Bell Telephone Labor Inc Counter circuit for providing a square-wave output
US3721904A (en) * 1970-03-07 1973-03-20 Philips Corp Frequency divider
US3617902A (en) * 1970-08-04 1971-11-02 Gen Electric Frequency multiplier

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6188258B1 (en) * 1998-11-27 2001-02-13 Mitsubishi Electric System Lsi Design Corporation Clock generating circuitry
US20120197553A1 (en) * 2009-09-29 2012-08-02 Abb Technology Ag Pressure transmitter for measuring the pressure of a process fluid and related method
US9417150B2 (en) * 2009-09-29 2016-08-16 Abb Technology Ag Pressure transmitter for measuring the pressure of a process fluid and related method

Also Published As

Publication number Publication date
NL7202492A (xx) 1973-01-03
CH540607A (de) 1973-08-15
SE391423B (sv) 1977-02-14
ZA724133B (en) 1973-03-28
AT313417B (de) 1974-02-25
JPS5829645Y2 (ja) 1983-06-29
DE2228008B2 (de) 1979-03-15
DE2228008A1 (de) 1973-01-18
GB1353128A (en) 1974-05-15
BE782384A (fr) 1972-08-16
CA961118A (en) 1975-01-14
JPS5515887U (xx) 1980-01-31
AU465762B2 (en) 1975-10-09
DE2228008C3 (de) 1979-10-31
AU4417172A (en) 1974-01-10
FR2144209A5 (xx) 1973-02-09
IT959983B (it) 1973-11-10
JPS4817658A (xx) 1973-03-06

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