summer traning jodhpur

1. Power Line Carrier
CommunicationTO FROM:
PROF.RAVI SONI PREETESH KUMAR ARYA
(PROF.,EE DEPARTMENT) (IV YR,EE)

2. Contant
 Training overview
 Company profile
 Introduction
 General modulation principle
 Basic principle of PLCC
 Specification
 Basic arrangement
 Wave trap
 Tuning capacitor
 Battery charger

3.  Technical specification
 Maintanance and fault traction
 Maintanance and fault traction procedure
 applications
 Advantages
 disadvantages
 Key learning
 Conclusion

4. Training overview
 Name of industry : Rajasthan Rajya vidyut prasaran nigam limited
 Location : 220KV BASNI GSS , Jaipur
 Duration of training : 20 may to 11 july
 Department of training : electrical engineering

5. About company
 RRVPNL started working from july 1957
 Sh.shailendra Agarwal,IAS is the chairman & MD of RRVPNL
 RVPN provides the pathway for power within whole rajasthan
 This is the body of big organization ACT, like public limited
companies
 It works as electric power distribution regulation within the state.

6. Introduction
 PLCC, Power Line Carrier Communication, is an approach to utilize
the existing power lines for the transmission of information.
 This technology has been in wide use since 1950 and was mainly
used by the grid stations to transmit information at high speed.
 Can use existing infrastructure for data traffic
 Involves a lot of technicalities.

7. General modulation principle
 Single side band transmission
 Carrier frequency is spaced on a 4KHz
 I.F. fixed at 16KHz
 Full duplex mode is used
 Lower side band is used throught all communication

8. Basic principle of PLCC
 The communication system cannot be directly
connected to the high voltage lines suitably designed
coupling devices.
 These usually consist of high voltage capacitor with
polaritical devices used in conjucation with suitable line
matching unit (LMU) for matching the impedence of line
to that of the coaxial cable connecting the unit of the
PLC transmit-receive equipment.

9. Specifications of PLCC
1) GENERAL:-
 Carrier frequency range:-40 to 512KHz
 Useful AF band:-300 to 3700Hz
2) TRANSMITTER:-
 Peak envelope power:-25W
 Side band power:-15W

10. Basic arrangement
 The basic arrangement of connecting the WT and coupling
capacitor in PLCC communication is shown in figure

11. Types of coupling
 A) phase to ground coupling

12.  Phase to phase coupling

13.  Phase to phase coupling

14.  INTERLINE OR INTER CIRCUIT COUPLING

15. Wave traps
 Wave traps – (WT’s) are used between the transmission line and the
power stations to avoid carrier power dislocation in the power plant
and cross talk with other power line carrier circuits connected to the
same power station

16. Tuning capacitor
 For lower voltage class of tuning units with impulse test voltage
rating upto 40 KV polystyrene capacitors are used
 For higher voltage class of tuning units with impulse test voltage
rating upto 150 KV, capacitors with mineral oil impregnated paper
dielectric are used
 Used are high voltage, high stability mica capacitors with low losses

17. Battery charger
 PLCC (Power Line Carrier Communication) works on rectified AC or
main power supply. When supply goes off, we use BATTERY CHARGER
for proper functioning of PLCC, which provides supply to the PLCC
equipment for uninterrupted working. It provides DC to the panel by
battery of 48V. In this type 24 batteries are connected in series and
individually per battery has approximately 2V capacity.
 Battery charger mainly consists of 4 sections –

 1. Float charger
 2. Boost charger section
 3. Control section
 4. Alarm section

18. Technical specifications
 NORMAL INPUT :415 V AC 3-PHASE
 INPUT VARIATION : +/- 20%
FLOAT CHARGER :
DC OUTPUT :50 V
OUTPUT CURRENT :20 TO 40 AMP
EFFICIENCY : >70%

19.  BOOST CHARGER
 DC output - 43.2 to 67.2 V
 Output current - 25-70 Amps.
 Efficiency - >80%

20. Maintanace & fault traction
 Fault analysis:
in fault analysis the faulty devices are checked in this
serial or manner:
1. Telephone or tele operation signal
2. Cabling low frequency circuit or DC power supply
3. PLC equipment
4. HF transmission path

21. Maintainance and fault traction
procedure
 The control circuit boards should be inserted far firmly.
 The charger should be switch off once in every month.
 The battery terminal should be connected first and AC input after
that.
 All mounting bolts should be checked before energizing.

22. Applications
 PLCC Unit Provide Five type of operation:
1:TELEPHONE FACILITES
2:COMPRESSOR & EXPANDER
3:EMERGENCY CALL
4:SIGNAL BOOSTING
5:SUPERVISION & ALARMS

23. Advantages
 No separate wires are needed for communication purpose.
 Both communication and power transfer can be possible on same
circuit
 Power lines provides the shortest route between the power station
 Increase reliability
 Lower attenuation over long distance
 Implementation cost is reduced

24. Disadvantages
 Reflection are produced on spur lines connected to high voltage
line this increased attenuation and create other problem.
 High voltage lines have transformer connections,which attenuate
carrier currents.
 Noise introduced by power lines is far more than in case of
telephonic lines.
 Proper care has to be taken to guard carrier equipment and
persons using them against high voltages and currents on the lines.

25. Key learning
 PLCC is mainly used for telecommunication,tele-protection and
tele-monitoring,between electrical substation through power lines.
 In a PLCC system the communication is established through the
power line.
 The carrier frequency range is allocated to include the audio signal,
protection and the pilot frequency.

26. conclusion
 Power line carrier communication has been found to be the most
economical and reliable method for communication in a medium
and over long distance in a power system.

27. Questions?

28. Thank you