Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B3/00—Line transmission systems
  • H04B3/54—Systems for transmission via power distribution lines
  • H04B3/542—Systems for transmission via power distribution lines the information being in digital form
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B2203/00—Indexing scheme relating to line transmission systems
  • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
  • H04B2203/5404—Methods of transmitting or receiving signals via power distribution lines
  • H04B2203/5416—Methods of transmitting or receiving signals via power distribution lines by adding signals to the wave form of the power source
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B2203/00—Indexing scheme relating to line transmission systems
  • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
  • H04B2203/5429—Applications for powerline communications
  • H04B2203/5433—Remote metering
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B2203/00—Indexing scheme relating to line transmission systems
  • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
  • H04B2203/5429—Applications for powerline communications
  • H04B2203/5458—Monitor sensor; Alarm systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B2203/00—Indexing scheme relating to line transmission systems
  • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
  • H04B2203/5462—Systems for power line communications
  • H04B2203/5466—Systems for power line communications using three phases conductors

Definitions

• Sine wave Sine wave and frequency at 50 Hz of the power supply Line current
• Half-wave Half-sine wave and frequency at 50 Hz of the power supply Line current
• Control Electronic unit with command functions
• Block Group of one or more Line Sine waves and/or Half-waves.
• LDS Line Data System
• 2nd Problem Necessity that the sensor Stations, when connected on a public lighting Line, continue to be fed and operational also during the hours when the luminaires are off, without having to use booster batteries or other support devices.
• the LDS finds its ideal technical field (currently preferred by the inventors but nevertheless indicative and not limitative) wherever there is the opportunity to use the electric power distribution Lines to propose applications; these include at least 3 sectors: 1 ) Transport (detection and management of vehicular traffic); 2) Pollution (climate and
• T environmental data recording stations T environmental data recording stations); 3) Management of electricity, gas, water, teleheating, etc. distribution networks.
• LDS makes it possible to create extensive and capillary acquisition networks with extra-urban and urban area coverage concerning the acquisition and communication of elementary, congruent and isochronous data, thanks to the easiness with which the recording Stations can be applied to any type of Line to
• Substantially LDS is composed of two different types of electronic units.
• the first is 7' ⁇ a Control unit and the second consists of the Sensor Stations for remote sensing, remote control and the like, to be installed in the field.
• the units feature valid innovative solutions, the most important of which include: 1) Synchrosys: this concerns the original method synchronous with the Line frequency to send control data and codes to the field units (Fig. 6).
• the method which uses un-modulated Tones, is managed by the Control units and uses the Line to obtain an extremely rugged and reliable communication system.
• the data and commands can be addressed indifferently to one unit, to a group of units or to all the various families of units installed in the field that use the same Line. Said data and commands start, synchronize, stop, modify the operational parameters of the field units and the data managed by these units.
• LDS operates on any type of Line and more than one system can co-exist on the same Line, also for different families and purposes, without any limitation and without interfering with one another.
• the operating principle is based on the employment of Tones inserted and synchronized with a Line Sine wave or Half-wave Block to communicate one Byte.
• the method permits communication protocols to be implemented, which are extremely simple and efficient when compared to the asynchronous types used by the PLC systems, as well as free from z:, interferences thanks to the signal (Tone) integration redundancy that can be effected by the receiver synchronously with the transmitter, thus avoiding the sending of parity Bits and or the repetition of messages.
• base Tones at different frequencies allows having on the same Line more Control units which manage independently, concurrently, without reciprocal limitations and interferences, various Station arrays, each relating to one same sy ⁇ tem or to different application systems.
• the method makes it possible not only to contain the basic industrial costs, but also to reduce to a minimum the occupation of the allowed and available frequency range. Lastly, since both Synchrodata and Synchrosys are synchronous with the line frequency, it is not necessary to introduce pauses between the sending of an elementary data and the next. Every instant of the Line time can be used to communicate data and commands (Figs. 4, 5 and 6).
• informatics terms the method permits implementing a communication management protocol of the Token-Passing synchronous type with a pre-determined sequence in case of group or all-units scan. With this method both the Control and the Stations connected to it can manage the communication protocol transparently without occupying, for this management, part of the Line passband which thus remains entirely available for the communication of data and commands .
• Smartpower features the original method whereby the sensor Stations, when installed on a public lighting system, remain fed and thus operational also whith the luminaires switched off, with no need for autonomous supply.
• LDS satisfies both application and economy demands in that it permits, using the existing Lines as they are, to implement monitoring and control systems extended over all the area served by the road network and the power, gas and water distribution networks.
• LDS can be viewed as one of the most original, innovative, economic and practical inventions, systems, methods or utilities known at present.
• the known techniques include:
• Accessory conductors Systems based on the use of accessory conductors to be installed beside the Lines. This method represents an apparently simple solution; however, it is costly as to both initial investments - in that the cables must meet precise isolation norms - and the additional maintenance costs linked to the vulnerability of the system due to the operational context: "The road”.
• Radio or telephone communications Systems that use radio units, dedicated telephone iines or similar solutions, are exposed to the same problems as the accessory conductors.
• DTMF Dual Tone MultHrequency: this is a call-routing telephone system which employs 2 tones at a time out of 8 available and is thus able to supply 16 different values.
• the system has been invented to overcome the problems of the present technologies and to be easily produced and installed by all interested parties with the result - as will be seen further on - of obtaining a more secure method of performance; the LDS invention furhermore, is the most economic of any system known so far.
• the general architecture of the LDS system is organized on 3 levels, as follows:
• This consists of one or more electronic units, intelligent and capable of managing, dialoguing with and receiving data from the field units. More Control units can depend on a same Supervision Centre but can also operate independently and autonomously.
• This level consists of field electronic units, intelligent and adaptable to multiple ' " ' uses, capable of managing one or more transducers of different nature for remote sensing, remote control and the like according to the various user demands.
• the Stations when installed on a public lighting system, can function also during the hours when the luminaires are off without need for booster batteries or other support systems.
• the various sections composing a Station are contained in a sealed, 1 eventually thermostated box, of pole or wall type, which can supply the voltages and currents required for the various types of transducers used.
• Fig.1 Shows the general block diagram of the system for remote sensing and remote control- Fig ⁇ Shows the general block diagram of the system for the remote reading of meters;
• F ⁇ g.3 Shows an application of the system between an individual phase and neutral
• Fig.4 Depicts the waveforms of the high speed Synchrodata communication
• Fig.5 Depicts the waveforms of the low speed Synchrodata communication
• Fig.6 Depicts the waveforms of the Synchronous command code by employing unmodulated Tones, synchronous with the Line Sine waves
• Fig.7 Shows the block diagram of the Control unit
• Fig.8 Shows the block diagram of a typical field Station.
• Fig. 1 Shows the general block diagram of the LDS system dedicated to sensing and remote control when installed on a public lighting system. The diagram is divided into two sections: In the "Power Delivery Point Section” is grouped the Control unit and in the “Field Section” are grouped the field units. On the left the incoming Line supply (1) and the power factor capacitor (2)
• the Teiedeflectors (3) are needed to insert the low voltage, 50 Hz Smartpower supply (4) to feed the Stations in the absence of the 220 Volt primary energy.
• the low voltage power supply applied to the Line does not concern the installed public lighting luminaires which thus remain disconnected.
• Such power supply voltage for the recording Stations (9) is inserted during the hours when the luminaires are switched off.
• the Teledeflectors (3) are kept closed r on the contacts towards the 220 Volt power supply. Upon lack of said power supply the Teledeflectors automatically switch on the standby contacts and introduce the low voltage supplied by (4).
• Control unit (5) sends the commands to the field via the induction circuit (6), one for each supply phase, and collects the data coming from the field i through an equal number of induction circuits (7) without connecting physically on the Line. Lastly, it communicates with an eventual Supervision Centre via a data transmission line (8).
• Fig. 2 shows the general block diagram of the LDS system where employed on phase to phase distribution networks. This type of connection permits also to translate the communication of data and commands between the medium voltage secondary and primary of a transformer.
• the exemplified diagram, relating to the remote reading of meters, is divided into
• the Control unit (14) sends the commands to the field via two induction circuits (15) and receives the data via two detection circuits (16) with which it obtains also the Line synchronism at 50 Hz. It shall be noted that the Control does not act directly on the Line current, from
• the reading Station (20) reads the values indicated by the transducers via a Demultiplexer (21 ) and keeps them in storage; it receives the commands emitted by the Control (14) via the detection circuits (23) and sends the data detected to the Control (14) via the induction circuits (22).
• the comparison is provided between the LDS system which employs a 1 ,600 Hz Tone and a PLC system which employs an 80 KHz frequency to transmit on a phase-to-phase distribution circuit.
• the LDS system can transfer, at equal time period, many more useful data than a PLC system with 1 ,200 bp ⁇ communication speed, it must be borne in mind that, to evaluate the power needed to transmit long distance on low voltage Lines, it is necessary to take into account the presence of power factor capacitors.
• Fig. 4 illustrates the electric diagram of the Synchrodata communication code waveforms.
• the principle upon which the communication is founded from the various field units to the Control unit consists in the modulation of the current of a Block of Sine waves by means of unmodulated Tones transmitted synchronously with the Sine waves.
• each unit will transmit in turn, according to the sequential order established upon installation, i.e. at the moment when the 50 Hz synchronous counting will correspond to the Block of Sine waves assigned as group sequence or Stations array sequence.
• the Control By analyzing the sequence of the various Blocks of Sine waves with identical counting system of the Stations and by recognizing the Tone sent in each segment of rhe Block, the Control is able to reconstruct the binary content of the communication made by the field unit, and recognizes its source.
• the three parentheses (33), (34) and (35) show examples of various Blocks; other cases can be developed maintaining the same principle of synchrony which is the essential object of this new technology.
• Line (32) shows the 50 Hz Line Sine waves
• sign (+) indicates the positive Half-waves and sign (-) the negative Half-waves;
• Each letter "R” shows the Result of ithe communication which is obtained according to the position of the Tones in the Sine waves or in the Half-waves;
• Parenthesis (33) depicts the case where each field unit is assigned 4 Line Sine waves to transmit a Byte using 4 different Tones.
• Unit 1 is assigned Block 1 which comprises Sine waves 1 to 4;
• Unit 2 is assigned Block 2 which includes Sine waves
• Tone "A” "0 0" binary value
• one of the 4 reference Tones is chosen and with it is modulated the Line current for the duration of one Sine wave.
• Block 3 composed of Sine waves 9, 10, 1 1 and 12 of said parenthesis (33), provides An example of the above-mentioned 4 Tone method.
• Parenthesis (34) shows how to use the method in the event that a higher communication speed is needed.
• the duration of the Line current modulation is reduced to only one Half-wave for each Tone, thus obtaining the possibility of communicating one Byte with 2 Sine waves, 2 Bytes with 4 Sine waves, and so forth.
• Parenthesis (35) shows how to use the method in case of a slower communication specially suitable, for example, for remote reading of slowly varying consumption meters. In this situation it is possible to use Tones of lower frequency and to :.7 proiongue the modulation of the Line current for 2 or more 50 Hz Sine waves, as better detailed in Fig. 5.
• the method permits to communicate any number of Bytes, one after the : other, until the necessary length of the message is reached.
• the Line current can be modulated for the period of one Half-wave or fraction of it or, of one Sine wave or multiple of it.
• a Tone can be used according to a binary logic 1/0 so that its presence/absence in a Block element allows sending and receiving the state of each of the Bits of one Byte. Assuming instead to have more elementary Tones available, it will be possible to associate to each binary configuration of n Bits a specific Tone, thereby obtaining increasingly faster communication techniques as the value of n increases in that, at equal time, it will be possible to transfer increasingly greater parts of a Byte.
• the optimal choice will be made by balancing the desired performance and the basic complexity of the system.
• Half-wave or fraction Sine wave or multiple will be made on the basis of the frequencies chosen as base Tones and the redundancy needed to reach the desired communication reliability.
• Synchrodata method of communication particularly suitable for monitoring systems regarding phenomena characterized by low variation speed.
• the adoption of Tones of appropriate frequency, associated to the presence of a Tone for multiple Sine waves, allows obtaining a communication free from disturbances thanks to the signal integration redundancy that can be effected by the receiver.
• Line (36) shows the 50 Hz Line Sine waves
• Line (37) shows the frequency "A" Tone which prolongues for 10 Sine waves and, for lack of space, a portion of the Tone "B" duration, and so forth;
• Line (38) shows the Tone "A" integration upon reception
• Line (39) shows the beginning of the Tone "B" integration upon reception
• Line (40) shows the moment in which the transmit/receive Tone is identified
• Fig. 6 illustrates the electric diagram of the waveforms of the Synchrosis code formulated and emitted by the Control for the command of the field units. It shall be noted that the current of a Line Sine waves series is modulated to generate binary codes corresponding to: Start Signal
• the method thus converts the 50 Hz Line low frequency into a brief and fast binary ! . code which can be sent on the Line independently from the flow of data the field units are sending to the Control.
• the Control can generate on the Line a powerful, complete and composite message able to satisfy any data and command communication requirement.
• the module that formulates the Code is contained in the Control unit which sends it via the induction circuits (see Figs. 1 and 2) which insert the Tone current synchronously with the Line Sine waves.
• the Start command emitted by a Control will synchronize only and solely all the field units relating to the application system controlled by it.
• a Synchrosys code diagram is shown, dimensioned for 16 commands and 64 addresses, but nothing prevents the concept from being reduced or expanded as needed.
• the code shown in the diagram uses a Block of 12 Sine waves configured as follows:
• Line (41 • A) shows the 50 Hz Line Sine waves
• Line (41 - B) shows the command code obtained by direct modulation of the Line current, particularly suitable for the Stations installed on public lighting systems
• Line (41 - C) shows the command code obtained by indirect modulation of the Line current, particularly suitable for the Stations installed on other distribution networks
• the code starts with the Start command formulated, in the example, with the use of the Tone in an "ON" Sine wave and one "OFF". This is followed by the command 77. code and the address of the field unit to which the command is addressed.
• Line (41 ) represents the command as emitted by the Control, while the subsequent Iines (42/49) show how said command is elaborated upon reception and detected by the field Stations.
• the Tone used for the Start signal can be different from the Tones used for communication of data, commands and addresses.
• Line (42) shows the result of the integration of the Tone. It shall be noted that the logic level is always high in the presence of the Tone ("ON" State) and low in the moments when instead the Tone is missing ("OFF" State);
• Line (43) shows the 50 Hz continuous Clock reproduced locally. This continuous form is furnished by the local system of generation compared and synchronized in phase with the Line Sine waves;
• Line (44) shows continuous pulses, shorter and shifted in phase towards the end - of each positive Half-wave. Each pulse is used to detect the absence or presence of the Tone in each Half-wave.
• the code shown in the example relates only to the positive Half- waves, but the same is done with the negative Half -waves and the two Results compared and summed up as per Results (46, 47, 48 and 49).
• Line (45) shows the output furnished by a comparator circuit AND (omitted) by comparing the previous levels of the forms (42, 43 and 44);
• Line (46) displays the Result of the Start command in the established interval of time
• Line (47) shows the control of the duration of the communication cycle of the
• Line (48) displays the Result of the command code in the assigned time interval
• Line (49) displays the Result of the field unit address code.
• the message will be . :: received by all the stations operationally connected to the Control that has emitted the command: All those enabled to receive the commands on that specific frequency of Tone, but only the addressed Station(s) will execute it starting from the end of the communication cycle: 13th Sine wave, in the example.
• Fig. 7 shows the block diagram of the Control unit divided into 4 sections:
• Tone reception The example shows the case of a 4 Tone Synchrodata communication.
• the task of the section is to separate and detect the Tones received rhrough:
• Microcontroller hereinafter: "CPU”
• Transmitter section Its task is to send the commands to all the Stations operationally connected to the Control, in a balanced way on the two phases:
• the CPU (64) collects from the matrix (56) the address of the
• the CPU is able to reconstruct the binary content of the information sent by the Station whose address is that determined by the circuit (56).
• the CPU For transmission of the commands the CPU enables the Push-Pull circuits (66 and ⁇ " 67) which function as current Drivers for the induction circuits (68).
• Fig. 8 shows the block diagram of a typical field Station divided for simplicity into 3 sections: Address Counters; Oscillator and Logic.
• the task of the address counters section is to count the 50 Hz Sine waves through:
• the task of the logic section is to manage all the Control unit through:
• Oscillator The task of the oscillator is to produce the Clock for the CPU and to generate the communication Tones which, in the explicative and not limitative example, are 4, through: (84) Oscillator circuit synchronized with the 50 Hz Line Sine waves;
• the CPU (76) analyzes the data of each Transducer via the interface (82), composes and retains in memory the various messages to be transmitted but waits for Matrix AND (75) to indicate the transmission Block corresponding to the command received. In fact, dependent on this command the transmission can and shall take place:
• the CPU On the basis of the turn assigned to the unit as group sequence or universe sequence if the command has been addressed, respectively, to a specific group or to all the units connected to that Control.
• the CPU actuates the Demultiplexer (78) to select the Tone to be used, as a function of the binary value of each pair of Bits of the Byte to be communicated, and enables the AND circuit (79) which will actuate the transmitter (80).
• the CPU is synchronized with the 50 Hz Line Sine waves by the circuit (77) through which it detects also the command code sent from the Control unit and sets up for the requested executions. In the event that an external device is addressed by the command, it will act through the Driver (83).

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Selective Calling Equipment (AREA)
• Control Of Transmission Device (AREA)

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• 1996
  • 1996-02-21 IT IT96RM000116A patent/IT1284281B1/it active IP Right Grant
• 1997
  • 1997-02-20 EP EP97905388A patent/EP0882332A1/de not_active Ceased
  • 1997-02-20 WO PCT/IT1997/000033 patent/WO1997031430A1/en not_active Application Discontinuation
  • 1997-02-20 AU AU22292/97A patent/AU712697B2/en not_active Ceased
  • 1997-02-20 BR BR9707661A patent/BR9707661A/pt not_active Application Discontinuation

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