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Power Line Carrier AMR . Ideal Technology for Caribbean Electric Utilities. What is AMR? . Automatic Meter Reading Basic Remote Collection of Meter Billing Information from a customer’s premise Advanced
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Power Line Carrier AMR Ideal Technology for Caribbean Electric Utilities
What is AMR? • Automatic Meter Reading • Basic • Remote Collection of Meter Billing Information from a customer’s premise • Advanced • Collection of other key information to assist in customer service improvement, maintenance, planning etc… Carilec Engineering Conference 2001
AMR – Popular Technologies • Radio Based • Fixed Network or Mobile Radio Receivers • Telephone Based • Landline or Cellular connection to the host • Power Line Carrier (PLC) • Direct Connection from the customer to a collection point over the existing current carrying power lines • Hybrids of the above Carilec Engineering Conference 2001
AMR – Popular TechnologiesAdvantages and Disadvantages • Fixed Radio Network • Can be read on demand (on-line) • Very quick But….. • Very expensive technology to install • Expensive and complicated to maintain • Not suitable for hilly or mountainous locations • Radio frequencies may not be available or allowed in that country (e.g. Spread Spectrum) Carilec Engineering Conference 2001
AMR – Popular TechnologiesAdvantages and Disadvantages • Walk or Drive by Radio Based Meter Reading • Transmitters are relatively low cost • Simple technology to implement But… • Not truly automatic as readers are still necessary (walk-by) • Vehicles are now needed (drive-by) expensive and costly to maintain • Some meters are difficult to read if they are far from the road/footpath • Radio frequencies may not be available/allowed Carilec Engineering Conference 2001
AMR – Popular TechnologiesAdvantages and Disadvantages • Telephone Based - Fixed or Cellular • Relatively low cost transmitters • Simple technology • Meters can be read quickly on demand But… • Very costly to read (Toll charges) • Customers consider the sharing of their telephone lines, a invasion of privacy Carilec Engineering Conference 2001
Power Line Carrier - Overview • Data Packets are sent over the existing power lines • Power Line is the transmission medium • No need for radio transmitters or telephone connections for each meter • Inherent on-line system design capability Carilec Engineering Conference 2001
Power Line Carrier TechnologyHow does it work? • Current frequency is used as the carrier • Information is sent in packets modulated on the current frequency (Carrier Frequency) by the remote transmitter • Signals demodulated at the collector end and information is then decoded to enable billing Carilec Engineering Conference 2001
Power Line Carrier TechnologyAdvantages • No need for additional expensive communication medium • Existing Power Line is the communication medium • System can be on-line, and can alert the utility of power problems if no signal is detected from the customer end • Transmitter Signal Strength can be used as a guide to the utility about maintenance issues Carilec Engineering Conference 2001
Power Line Carrier TechnologyDisadvantages – (Traditionally) • Transmitter power demands are high to increase the signal travel distance • Transmitters are large due to large power requirements • Signals may not travel well through transformers or capacitors • Signals easily affected by noise on the lines • Applications are limited to short distances due to the above factors Carilec Engineering Conference 2001
Power Line Frequency Power Line With Carrier Transmission through transformer and capacitor banks Power Line Carrier TechnologyDisadvantages – (Traditionally) Some data is attenuated and lost Carilec Engineering Conference 2001
Revolutionized Power Line Carrier Technology Carilec Engineering Conference 2001
Power Line Carrier TechnologyRevolutionized (some types) • Uses a Smaller Signal Bandwidth • Needs a lower transmit power • Transmitter size is reduced • Modulated on a 120 Hz Current Carrier • Slow but Sure transmission • Signal passes through transformers etc. • Continuously Transmits Data • Take advantage of “On-line System” benefits Carilec Engineering Conference 2001
System Bandwidth Transmission Power TV 6MHz 200 Kw Radio 10 KHz 1 Kw PLC .0015 Hz .0003 w New PLC TechnologyWhy it now works • Reduced Bandwidth • Slower data transmission but results in reduced transmitter power needs • Even though low powered, this easily overcomes transmission losses Carilec Engineering Conference 2001
New PLC TechnologyWhy it now works • Reduced Bandwidth Cont’d • Many channels (hence transmitters) in a small frequency band e.g. 5-10 Hz • Low Frequencies • (5-10 Hz) propagate very well through distribution lines • Low Frequency = Long wavelength, avoids standing wave problems • Hardly affected by capacitors, or line length Carilec Engineering Conference 2001
New PLC TechnologyWhy it now works • Modulated on 120 Hz current carrier • Data sent at zero crossing where least noise is present PLC AMR Carilec Engineering Conference 2001
New On-Line PLC AMR Financial and Operational Benefits
New On-Line PLC AMR Financial Benefits • Low Transmitter cost • Low Recurrent reading costs • Fewer/no meter reading personnel • Fewer/no meter reading vehicles • Very low data collection costs • Very low maintenance/operating costs • Robust equipment • High MTBF Carilec Engineering Conference 2001
On-Line PLC AMROperational Benefits • Notification of Power Loss • Loss of transmitter signal indicates possible loss of power at customer premise • Loss of several transmitter signals in an area, provides information on locating that problem easier and faster • Signal Strength Reading • Poor/deteriorating transmitter signal strength could indicate need for customer premise connection maintenance, distribution transformer problems, or need for line maintenance. Carilec Engineering Conference 2001
On-Line PLC AMROperational Benefits continued • Load Information • Peak KWh values and times assists the utility in sizing transformers and loading them correctly • Power Theft Indication • Frequent transmitter signal loss from customer premise could indicate removal and re-installation of the meter (upside down) whereby meter will decrement instead Carilec Engineering Conference 2001
On-Line PLC AMROperational Benefits continued • Power Theft Indication • Discrepancies between power supplied and power billed could indicate customer bypassing meter Carilec Engineering Conference 2001
Power Line Carrier Technology Why is it applicable for Caribbean Electric Utilities
On-Line PLC AMRIdeal for Caribbean Electric Utilities • Deployment is quick and less expensive • Doesn’t require much deviation from normal operations • Not capital or labour intensive • System is online from inception • Allows the utility to install as needed but getting all of the advantages for the first transmitter onwards • Readings not dependant on media from other utilities • E.g. Wire line or Cellular Telephone Carilec Engineering Conference 2001
On-Line PLC AMRIdeal for Caribbean Electric Utilities • Signals not affected by topography (Hills etc.) • As in the case of wireless solutions • No problems with radio frequency assignments • 900 MHz spread spectrum not allowed in all islands • Customer Service is improved • More information is available to the electric utility, on demand, for better customer service. No estimated billing, and fewer billing queries. • Service Levels are improved • Available information can assist in developing routine and unscheduled maintenance systems Carilec Engineering Conference 2001
On-Line PLC AMRIdeal for Caribbean Electric Utilities • Technology of choice in new project deployments at electric utilities • 32 of 49 in 2000* • 94 of 156 in 1999* • 31 of 51 in 1998* * Source AMRA Trials and Installations Reports Carilec Engineering Conference 2001
On-Line PLC AMRCompany Wide Benefits • Billing/Revenue Department • Immediate billing can be given on demand • Bill queries can be settled easier from easily available archives • Operations & Maintenance Departments • Online system can provide information to guide decisions in transformer sizing, load balancing, and line maintenance • Online power quality and end of line voltage measurement also possible Carilec Engineering Conference 2001
On-Line PLC AMRCompany Wide Benefits Cont’d • Customer Services Department • Elimination of estimated billing queries • Resolution of irregular billing complaints by scrutiny of archives • Proof of “Power Supplied” when customer makes claims about damages due to loss of supply • Meter Reading Department • Far more efficient and cost effective process Carilec Engineering Conference 2001
Power Line Carrier AMR Ideal Technology for Caribbean Electric Utilities