AC POWER LINE CARRIER COMMUNICATION
Short Description
This is a project on Power Line Communication...
Description
1. Introduction 1.1 Background & Need Data Transmission in the twentieth century mainly meant the transmission of telephonic data over the wires. This had many disadvantages. Telephonic Equipment is comparatively costlier. Telephone Circuits were often unreliable. Telephone Lines were found to be unable to sustain the harsh weather conditions in the mountainous terrain and the extreme weather. In addition the electrical interference between the parallel power lines and the telephone lines was a case of concern. On the flip side the power Lines were much more robust and reliable. Since power Lines were already available it made much more sense to use them rather than investing in the making of new lines. Power Lines Communication was gaining a lot of ground in the early twentieth century. The advantages that were offered by the implementations of this technology and its social and economic impacts led to many companies investing in this technology and using it in their own grid. These Companies (GE, WestingHouse and much later AT&T) pioneered the development of this technology. [1] “At Last Successful Telephone Communication has been conducted over live High-Tension Lines by the AG&E which has been convinced thereby that the method employed will solve one of its most important problems, namely insuring a reliable and less expensive mode of communication between its load dispatchers and interconnected stations. The test which proved the practicality of the method was conducted on July 7th and July 8th between the company’s Atlantic City and Ocean City Stations, over a live 11,000kV, 60 cycle line 12 miles long. [Adding Transformers and an underground cable, the equivalent length was 22 miles. The system employed works on the principle of wireless or directed radio. The carrier current for the communications had a frequency in excess of 5000 cycles[2]. Among the chief advantages the investment and maintenance expense connected with private lines are eliminated, high 1
rental charges for leased telephone lines avoided no interference from power circuits or static is experienced. the system can be used with any voltage transmission system, the possibility of power circuits breaking is remote, and even if they all fall to the ground communication will still be maintained. .. the investment for the apparatus will be around $500 station... more economical than an ordinary wired telephone system . Audibility is higher than with ordinary telephones[AG&E] is planning to apply the communication scheme to all of its properties for system load dispatching” 1.2 Commercialization of Power Lines Communication Systems GE was the first company to commercialism the use of carrier current telephony over power lines. The cautious optimization of the companies led to an almost stagnation of this technology around the 1930’s[3]. Instead of using the antennae, the number of households using coupling capacitors was increasing but not at the desired rate. Cost Cutting measures on the other hand put these measures on the back burner.
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2. Problem Definition 2.1 Why PLCC is not widely used till now? PLCC has its advantages. The PLCC systems though did have their limitations. These limitations which could not be overcome at the time due to technological constraints, paralyzed the infusion of this technology into the mainstream power transmission grid. Power Line Communications could not be used to transmit data over larger distances. This affected the bit rate being made available to the user. Power Lines Communications can be roughly categorized as Narrow Band Power Lines Systems and the Broad Band Power Lines Systems. The Narrow band PLC have a slower data rate(3 - 500Khz), lower Data Rates (100kbps) and are used over larger distances(several kilometers). The Wideband PLC work at higher frequencies (1.8 - 250 Mhz), have higher data rates (100Mbps) are mainly used for BPL ( Broadband over Power Lines). Power Lines Communications was simplex till the early 1980’s. This means that data transmission was possible in a single direction. Duplex transmission on an efficient basis was first undertaken during the 1980’s. After this the viability of the PLCC on a regular basis became more feasible. [4] The equipment needed for the Power Lines was extremely costly. The high installation cost hindered the foray of the power companies into PLC. Moreover the dormancy of this technology due to these constraints in the earlier days really put this technology on a back burner until much later when it was thought it is much more advantageous to utilize PLCC.
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2.2 Noise Due to Devices Connected to Power Line The electrical noise present on a power line when a device is operational is called conducted elector-magnetic interference , which can be classified into two types: transient and continuous. Transient noise is characterized by the short duration for which it can be observed, generally few tens of nanoseconds to a few milliseconds. Continuous noise on the other hand can be observed for as long as the device is operational. Both transient and continuous noise can either be concentrated within a narrow frequency band or spread over a wider bandwidth (also called broadband noise). A compact fluorescent light bulb (CFL) is an example of a device that generates continuous noise, which is conducted over the power line due to its physical contact with the power line. Since a home's electrical distribution system is interconnected in parallel at the home's circuit breaker panel, conducted EMI propagates widely from a given device throughout the electrical infrastructure. Table shows the different frequency at which devices generate noise.
Device
Noise Generated at Frequency
TV Turning ON 115Khz Laptop Charger Unplugged 114Khz CFL Bulb 50Khz – 110 Khz SMPS 1 – 40Khz LCD Monitor 64Khz PC 30 Khz – 45 Khz Various Household Appliances 150KHz – 500 Khz After analyzing the above data we came up to a conclusion that it is best to send FSK modulated signal over the power lines at frequency between 75KHz – 105KHz. 4
3. Final Goals Our goal is the successful transmission of data over the AC power lines. In addition to error free transmission we aim at making the system cheaper, portable and user friendly. Our aim is to create a user friendly plug and play type device in the form of a transceiver modem which would provide easy to use and cheaper (almost free) communication. PLCC is a very promising technology with many probable applications which would immensely benefit all. Through our project we look forward to contributing to this technology and search for ways to make it more consumer friendly.
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4. Literature Survey 4.1 IEEE Paper Study A Power Line Communication Tutorial - Challenges and Technologies, Phil Stutterlin and Walter Downey, pp 4-6.
The Power Lines available today were built for the purpose of power transmission from one place to another. The attempt to transmit data over these power lines leads to the reception of a lot of noise. This noise is due to the numerous devices connected to the power lines. An analysis of this noise and their characteristics helps us better understand how to tackle the problem of noise elimination in the Power Lines. The characteristics of the modulation techniques and their subsequent analysis gives us an idea of the advantages and disadvantages of each technique. The receiver contains a phase locked loop. We studied the modulation techniques and compared their performance in the present of noise. Finally Spread Spectrum technology is reviewed for the use of communications on Power Lines. Spread Spectrum is a method of signal modulation where the transmitted signal occupies a bandwidth considerably higher than the minimum necessary to send the information and some function other than the information being sent is used to increase this Bandwidth. Spread Spectrum was found to be unsuitable and rather detrimental for the PLCC system. Inference : After carefully studying the various technology we infer that Digital Signal Processing is absolutely necessary for the system to function efficiently. Spread Spectrum is found to be having a negative impact on the output and hence should be avoided. FSK is found to be the most immune to noise and hence chosen for our project.
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Active Filter Design Techniques, Op-Amps for Everyone, Texas Instruments, Literature no. SLOAO88
One of the problems while designing a PLCC based system is the reception of or the extraction of only the desired data signal from the power line at the receiver site. For this we need a filter which has a high order filter which can pass a definite band of frequencies only. The specifications here become very stringent so as to avoid any noise and 50Hz signal from the power line. The suitable candidate for this a Band Pass Filter with a reasonably high order so as to suite our requirements. The technique to design a BandPass filter which would be used to design the filters of the Power Line Communication Circuit has been studied in detail. The implementation of this design depends on the considerations of the practical available values of the components. Inference : The designing techniques of the filters at the receiving end are enhanced by the use of Band Pass Filters. Band Pass Filters gives us more customization in terms of defining our required window of frequencies.
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4.2 Existing PLCC Standards European Committee for Electrochemical Standardization (CENELEC) The European Countries collectively have formed an organization for the standardization of issues and concerns related to power lines communication. This standard defines standards for allowed frequency range and output voltages for communication over power lines. A frequency of 3 to 148.5 kHz is allowed for communication and this range is further subdivided into 5 sub bands.[7][8] Band
Frequency Range 3kHz-9kHz
A Band
9kHz-95kHz
B Band
95kHz-125kHz
C Band D Band
125kHz-140kHz 140kHz-148.5kHz
Usage This range is restricted to energy providers Restricted to energy providers and their concession holders Restricted to consumers Restricted to consumers. No access protocol is defined for this band.
Federal Communications Commission (FCC) This is the regulator for the USA. It has defined standards to be followed in the specific frequency range allocated for PLCC.[9]
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IEEE 1901 Institute of Electrical and Electronics Engineers (IEEE) stated a standard named IEEE 1901 for high speed power line communications. This group was formed in 2005 and gave its first standard in 2010 which includes two different physical layers, first one based on OFDM modulation and the other one based on wavelet modulation.[8] HomePlug Power Lines Alliance Home Plug Power Lines Allowance is a group of companies dedicated to the improvement of networking technologies across Power Lines. In June 2001 the first specification named Home Plug 1.0 was launched.[9] Products launched under the Home plug Standardization target in house usage of power lines communication. The costs of these equipments has been significantly reduced over subsequent years. An easy to use interface along with the cheaper cost has helped in propelling these devices made on this standardization.
Illustration 1: Home Plug PLCC Module
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5. Market Research 5.1 Product Study The Home Plug Alliance, a non profit Industry Association was formed in March 2000 by a group of industry leading companies to enable standards based PowerLines networking products. The first Industry standard was released in June 2001.This alliance consists of members such as GE Electric, LG, SONY, QualComm etc. Home Plug pioneered the way in developing high speed data rate for PLCC. Extensive Field tests conducted by it helped in the process for increasing the data rate and studying the path for the development of the this technology.
Illustration 2:
HomePlug uses OFDM coding for the coding of the data before transmission. The focus of HomePlug has been distributed on three broad categories namely Physical Layer throughput, MAC Layer Throughput, TCP Layer Throughput.[13] MSEB uses the PLCC technology for communication within its network. The routers and the repeaters ensure the transmission of data overcoming the attenuation losses over large distances. Multiple Sub 10
Stations are connected to the Main Station in an area. These main stations can facilitate as nodes. They route the data signal that is coming from a particular substation to another substation. During this path there is need for coupling circuitry which would ensure that there is now power feedback into the system. If along with the data power enters the communication medium it can wreak havoc to the entire communication as well as the Power Distribution System. The coupling circuitry ensures that the high Voltage Transmission lines do not interfere with the Communication process. At MSEB , there are multiple layers of modulation and filtering. This is to ensure that the data is highly secure as well as noise free. MSEB utilizes Amplitude Modulation. Amplitude Modulation does have a lot of disturbance on account of it being extremely prone to noise. As such the only utilization until now in the PLCC system being utilized at MSEB is for voice transmission. This has ensured that the communication systems stay up at all times. Obviously Back up communication mediums such as mobile phones are available in case of a power failure. UPPTCL [b]Similar to the MSEB in Maharashtra the UPPTCL also uses the PLCC technology for internal use. The wideband communication link is the link that specifies the connection between the substations as specified in the previous para. BPL BPL Telecom is the manufacturer of PLCC equipments. It integrates all the different types of communication media with the existing Transmission and Terminal Equipment network using its latest state-ofthe-art digital switch. The equipment can be configured for “speech-plus” operation (simultaneous transmission of speech and audio tones).[11] When used for data one, each channel can carry up to twenty four 50 baud telegraphic/data channels or a smaller number of channels at higher baud rates. Elements of the system may also be used for transmission over cable, open-wire lines, and radio multiplex applications 11
5.2 Site survey MSEB is a company that uses PLCC for its internal communication. It’s proximity to our city endeared us to visit the MSEB office for further details on their usage of the technology. We first visited the MSEB office at Kharghar. The executive engineer listened to our project and showed a lot of interest in the execution of our project. He directed us to their power distribution center at Airoli. We met Mr. Lokare at Airoli. Apart from the concepts we understood the problems faced while transmitting and receiving the data and more importantly we learned the ways that can help us overcome these problems. For eg. The problems of coupling between the circuitry and the power lines could be achieved by using a coupling capacitor and transformer. The way the routing of data takes place from a substation to another was explained properly. We got to see the complex circuitry that help this kind of communication possible. MSEB uses Amplitude Modulation for its data transmission. There are multiple levels of filtering and modulation. They even showed us their telephone modems that uses PLCC. Our visit was truly fulfilling as it paved the way for a better and more refined thinking from our side. The visit redefined our ideas and strengthen our confidence and belief in our project “Power Line carrier communication”.
Illustration 3: MSEB Power Sub Station, Airoli 12
6. Related Theory 6.1 Block Diagram
Analog Data
MC
ADC
For
FSK modulator
Step Up Transformer
Coupling Circuitry
Error Control Digital Data
AC Mains 230V / 50Hz
Coupling Circuitry Analog o/p
DAC MC For Data Recovery
Digital Output
FSK Demod
Band Pass Filter
Step Down Transformer
Drawing 1: Basic Block Diagram
This block diagram shows a brief overview of the progress of the data as it travels through the system. After applying the block codes to the digital data, the data is converted to its analog counterpart using FSK modulation. FSK modulated signal is stepped up and then sent to the AC power lines via the coupling circuitry. This marks the end of the transmission. 13
At the receiver end, the signal is first stepped down and then filtered in order to remove the unwanted noise elements. The modulated data is demodulated at the FSK demodulator. The data is then extracted by using the micro-controller coding. Finally the digital data is converted to its original form (analog/digital). 6.2 Data Flow in PLCC System The system mentioned above is compatible with both analog as well as digital data. Analog signals have infinite number of values of amplitude whereas Digital signals have only limited number of values. Source of analog data can be anything like voice from microphone or any audio signal which is required to be transformed. But analog data can't be directly coupled to a power line because analog data has infinite samples and such infinite values of amplitude can't be transmitted in a communication system because each communication system or communication module is associated with bandwidth restrictions which can't be overruled. Hence sampling (to convert analog data into finite number of samples) and especially utmost part of sampling that is analog to digital conversion is required for reliable transmission. From here the signal is fed to the Micro-controller block. Micro-controller that we would be using is the AVR series ATmega 328. In order to minimize the cost and production time we prefer using the Arduino Uno Board. The main purpose of controller here is to do coding so as to facilitate Error Detection & Correction. For this we would be using Block coding and Parity techniques. It's to ensure that the data to be transmitted should not get corrupted by noise and if it does get then necessary steps would be taken to avoid it. In block coding we divide message into blocks each of 'k' bits called data words. We add r redundant bits to each block to make the length n= k+r. The resulting nbit blocks are called codewords. So accordingly the input to the controller is a data stream which would be converted to codewords using a software program written in 'c' programming language. Here one 14
important thing to be noted is that is that block coding process is one to one; the same data word is always encoded as the same codeword. This means that we have 2n - 2k codewords that are not used. We call these codewords as invalid or illegal. So now the data is out of the controller and is forwarded to the modulator. Modulation is the process of translating low frequency baseband signal to high frequency high bandpass signal. The need for modulation here is to mainly transform digital signal into equivalent analog signal using a form of modulation known as Frequency Shift Keying(FSK) and also to translate it to a higher range of specially selected frequencies so as to keep the data safe from noise interferences. For making this implementation of a modulator we would be using a specially designed modulator chip called XR2206[17]. We have selected XR2206 as a FSK modulator because of its capability of producing high quality sine and pulse waveforms of high stability and accuracy. Low sine wave distortion and excellent temperature stability are also the factors which make us zero in on its selection as FSK modulator. [14]
Illustration 4: XR2206 15
Figure above shows the way in which XR2206 is used as FSK modulator. Resistors R1, R2 & Capacitor C are our design variables. R1 is related to mark frequency and R2 is related to space frequency. So depending our requirement we can select appropriate values of the design variables. The output of the FSK modulator is a signal of amplitude between 5-10 volts. In order to introduce this signal on the power line we need to step up it up to 25-30 volts. This may be required as 5 volts signal from modulator output may not survive on the power line of 230 volts. For this purpose we use a step up transformer. The main preference while choosing a transformer is that it should pass the high frequency signal from FSK modulator to the power line without distorting it. The iron core transformer may saturate at this high frequency(87k-102k) thus distorting our required signal. Thus what we need is a ferrite core transformer which best suits our demand. One of the most critical components of any Power Line Communication (PLC) system is its interface circuit (or coupling circuit) with the power distribution network. This is by no means a simple unit considering the challenging characteristics of the PLC channel. The coupling circuitry forms the backbone of the PLC system Due to high voltages, varying impedance, high amplitudes and time dependent disturbances, coupling circuits need to be carefully designed to provide both the specific signal transmission with the appropriate bandwidth, and the safety level required by the applicable international standards. The superimposing of a PLC signal on a power waveform implies that the coupler circuitry and power circuitry would have to be carefully designed and interfaced for optimal compatibility between the two systems. In PLCC, Power system and the communication system operate at the two extremes – power system at very low frequency and very high power, current and voltages levels and communication systems at much higher frequencies and very low power, current and voltage levels. To be able to design PLC systems as well as to supply a proper interface 16
between power and communication system the coupling circuitry is must. The purpose of the coupling circuits is two-fold. Firstly, it prevents the high voltage 50 Hz signal, used for power distribution, to enter the equipment. Secondly, it certifies that the major part of the received/transmitted signal is within the frequency band used for communication.
Illustration 5: Coupling
In practice the coupling is achieved by connecting a 47nF (230V) capacitor with a 1:1 transformer. The capacitor posses a very high impedance to the 50Hz power signal and allows HF signals to pass through it. The purpose of the transformer is to provide electrical isolation. The figure above shows the idea described above. Now that we have taken every possible precaution for data integrity and safety of equipments, we are ready to introduce our FSK modulated stepped up signal on to the power line. What would practically happen is that our modulated signal will ride on the 50Hz Sine wave o power line.
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Illustration 6: 50Hz Signal with data modulated on it
Illustration 7: Zoom version on 50Hz signal
After the data has traveled all the way and reached the destination the next important thing is to accept this combined(50hz + FSK signal) signal through a coupling circuitry. The use of coupling circuitry will be same as stated in the above paragraphs. The received will be at 230 volts, therefore we need to step down it before proceeding. This is done with the help of a ferrite core step down transformer. Power lines tend to have a lot of interference due to the various devices connected such as SMPS, Welding machines etc. So the final signal that we receive at the receiver is an integration of our FSK data, 50Hz power line signal and noise. We have to extract the FSK signal from the this received signal. To achieve we initially tried to use a High Pass Filter. However this did not reject the High Frequency Noise. Thus the idea of using the Band Pass Filter was thought of. The Band of frequencies chosen for the Band Pass Filter is from (86k-103k). This range eliminates two things. It rejects the 50Hz Power Lines signal as well the noise from the high frequency range (above 200Khz). This has already been explained in brief previously in pg. (4).The design of the BPF was undertaken with these frequencies(86Khz and 103Khz) as the range .
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Illustration 8: Noise addition
The resultant signal out of the BPF is the FSK modulated signal. In order to extract the desired data we need to pass it through the FSK demodulator circuit. We use a specialized monolithic IC XR 2211[16] for this purpose. Because of wide frequency range (0.01Hz to 300KHz) and wide voltage range (4.5V to 20V) XR2211 is selected as Demodulator .The XR 2211 is a specially designed monolithic Phase Locked loop IC for demodulation of FSK. The design variables and constants for using XR 2211 for FSK demodulator are provided in the Data Sheet of XR 2211[15]. The data that we receive from the output of the demodulator is in the form of ‘code words’. In order to extract the original data from these code words we need to pass these code words into the micro controller. Here a software program will separate the required data from the redundancy bits. The output of the micro controller is serial and digital in nature. Depending on the application we can use this output either in its digital form or we can convert it into analog form using an DAC. This is the data that we required. The data achieved at this point should be free from errors. This data should be in the same format as was transmitted at the transmission end. 19
7. Softwares NI LabVIEW LabVIEW (short for Laboratory Virtual Instrumentation Engineering Workbench) is a platform and development environment for a visual programming language from National Instruments. The purpose of such programming is automating the usage of processing and measuring equipment in any laboratory setup. LabVIEW is a graphical programming environment used by engineers and scientists to develop sophisticated measurement, test, and control systems using intuitive graphical icons and wires that resemble a flowchart. It offers unrivaled integration with thousands of hardware devices and provides hundreds of built-in libraries for advanced analysis and data visualization – all for creating virtual instrumentation.
Arduino Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments. Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The micro controller on the board is programmed using the Arduino programming language (based on Wiring) and the Arduino development environment (based on Processing). Arduino projects can be stand-alone or they can communicate with software running on a computer (e.g. Flash, Processing, MaxMSP). 20
MutiSim NI Multisim (formerly MultiSIM) is an electronic schematic capture and simulation program which is part of a suite of circuit design programs, along with NI Ultiboard. Multisim is one of the few circuit design programs to employ the original Berkeley SPICE based software simulation. Multisim was originally created by a company named Electronics Workbench, which is now a division of National Instruments. Multisim includes microcontroller simulation (formerly known as MultiMCU), as well as integrated import and export features to the Printed Circuit Boardlayout software in the suite, NI Ultiboard.
Processing Processing is an open source programming language and environment for people who want to create images, animations, and interactions. Initially developed to serve as a software sketchbook and to teach fundamentals of computer programming within a visual context, Processing also has evolved into a tool for generating finished professional work. Today, there are tens of thousands of students, artists, designers, researchers, and hobbyists who use Processing for learning, prototyping, and production. For our Project we will be using processing with Arduino Board, so as to have GUI to control the transmitter functions.
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8. APPLICATIONS Power line networking offers several advantages over other available home networking technologies; the availability of power outlets in abundance in every home and offices , it eliminates the need of laying new wiring. PLCC technology can be deployed into different types of applications in order to provide economic networking solutions. Hence merging with other technologies it proves useful in different areas. These are few key areas where PLC communications are utilized: a. Transmission & Distribution Network: PLCC was first adopted in the electrical transmission and distribution system to transmit information at a fast rate. b. Home control and Automation: PLCC technology is used in home control and automation. This technology can reduce the resources as well as efforts for activities like power management, energy conservation, etc. Plug the adapter into any existing power sockets and you can program it to control other modules over your AC wiring. You can program all the switch modules in the house in a single unit and you can remotely switch lights, televisions, Audio-visual equipment and other appliances on and off with a touch of a button --- A handy controller for Home Automation. The Programmable Controller and the corresponding Switch Modules are configurable at the host station. An LCD screen shows the operating status of the modules under control. In modern homes, there is a huge requirement of sending digital information, audio, and video all over the home. Running new wires to support this will increase the burden and cost of maintenance. To overcome this, PLCC is the right choice to implement Home Automation concept. Home automation or also known as Smart Home technology is a collection of systems and devices in a home that have an ability to interact with each other or function individually in order to be optimized 22
in best way. Using PLCC technology, existing power wiring of the house is used to connect home appliances with each other as well as with internet. Architecture of a PLCC based home automation system is shown in the above image. Various home appliances are connected within a loop through the existing power cables. This technology can connect each device with the network which is connected to an AC outlet. All appliances are also connected with a centralized control panel which controls them. c. Entertainment: PLCC is used to distribute the multimedia content throughout the home. d. Telecommunication: Data transmission for different types of communications like telephonic communication, audio, video communication can be made with the use of PLCC technology. e. Security Systems: In monitoring houses or businesses through surveillance cameras, PLCC technology is far useful. The surveillance cameras connected over Power System in a light bulb is unique; simply screw it into any light socket. Hidden inside the "bulb" is a sophisticated Low-Light Monochrome Camera, coupled with PLCC circuitry. The video signal is "encoded" by this circuit and fed directly to the power line. Each Video Over Power System features a companion Decoder, which plugs into any wall outlet. A typical homeowner would plug in the decoder at the outlet nearest the TV. A standard video output connects the decoder to any TV or VCR using line-level RCA-type cables. Once the Decoder is plugged in and connected, live video is delivered to the TV or VCR. It's simple and easy. There are no wires to run, no holes to drill, and no antennas or complicated "tuning" is required.
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f. Automatic Meter Reading– Automatic Meter reading applications use the PLCC technology to send the data from home meters to Host Central Station. Automatic Meter Reading using PLCC technology is quite useful as it saves a lot of human efforts and also makes the whole system more efficient. The automatic meter reading system consists of three components, namely, Multifunction Node (MFN), Concentrator & Communication Node (CCN) and Operation & Management System (OMS). Different components and their inter-connections are shown in the figure.
Illustration 9: AMR
MFN is a unit installed in household meters, either incorporated in the meter itself or externally connected to it. Its function is to take reading of the meter on an hourly basis and store it in a memory chip. CNN is another part which manages all MFNs within a particular area and collects meter readings from all MFNs. It is generally installed on substations and needs a computer. The computer is installed with Operation and Management System (OMS) which further manages all the data and meter readings from CNNs. 24
9. Conclusion The project has the capability of transforming the information highway in India. In a way that India has bypassed the landline telephone revolution, the adaptation of PLCC can help propel India into an elite group of countries with a very deep Internet penetration. This would in turn help in dispelling the superstitions and ignorance that prevails in some of the backward areas of the country. India’s image as a low cost development country in the world would get a major boost by the implementation of this technology on a wider scale. Power Lines Communication would result in a very large scale savings of the tax payers money. Efficiency of the existing infrastructure would be enhanced thus giving more value for money. This project is aiming at decreasing the value of the PLCC system further. It aims to ensure that the PLCC system can be used as a plug and play device without any major investments on the part of the consumer. PLCC is a technology that has the potential to change the lives of the citizens if factors such as cost, effectiveness and security are handled.
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10. References [1]“Interplant Telephonic Communications Established Over HighTension Lines”Electrical World vol. 76, July 17, 1920,p.141 [2]T.Johnson, Jr., “Recent Developments in Power Line Carrier, Electrical Engineering,’ Vol53, April 1934 p. 543-640 [3]AIML Journal, Volume (7), Issue 1 , June 2007 [4]http://ntrg.cs.tcd.ie/undergrad/4ba2.05/group13/index.html [5]A Power Line Communication Tutorial - Challenges and Technologies, Phil Stutterlin and Walter Downey, pp 4-6 [6] Dinesh ka references [7]http://www.cenelec.eu/index.html [8]http://www.engineersgarage.com/articles/plcc-power-line-carriercommunication [9]http://www.fcc.gov/ [10] https://www.homeplug.org/tech [11] http://bpltelecom.com/telecom/tsg/tsg/htm [12] http://upptcl.org/tech_info/power_system.htm [13]“HomePlug 1.0 Technology White Paper” pp. 6 [14] http://www.ti.com/solution/power_line_communication_modem [15]” Analog Design Filter Techniques”, Op-Amps for Everyone, Texas Instruments, Literature Number SLOD006A, pp.28-32 [16] “XR2211 FSK demodulator/Tone decoder”,EXAR Corporation.pp 14 fig 11. [17] XR-2206 Monolithic Function Generator,EXAR June 1997-3
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11. Index Numerical 87Khz-102Khz,16 3-148.5Khz,8 47nF,17 50Hz,17 A Arduino, 20,14 ATMEGA, 328 14 Automatic Meter Reading, 24
B BandPass Filter, 18,7 Block Coding, 14 BPL, 11
C CCN, 24 CENELEC, 8 CFL, 4 Coupling Circuit, 16
D DAC, 13 Demodulator, 19 EMI, 4
F FCC, 8 FSK, 15 I IEEE 1901, 8
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L LabView, 20
M MFN, 24 Modulator,15 MSEB, 12 MultiSim, 21
N Noise, 3,4
O OFDM ,9 OMS, 24
P Parity Techniques, 14 PLCC, 1,5,3,14,16 PLL ,19 Processing 21
U UPPTCL, 11
X XR 2211, 19 XR 2206, 15
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Photos
Illustration 10: FSK Waveform
Illustration 11: XR2206 Setup 29
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