This document provides an overview of power line carrier communication (PLCC) technology. PLCC uses power lines to transmit speech, data, and teleprotection signals between substations in a cost effective and reliable way over medium to long distances without requiring separate communication wires. The key components of a PLCC system include a line matching unit, coupling capacitor, transmitter, receiver, and wave trap to isolate the power and communication signals on the lines.

1. POWER LINE CARRIER
COMMUNICATION
PRESENTED BY
MOHIT AGARWAL
CGI/ECE/ 7TH SEM/15

2. INDEX
• TRAINING OVERVIEW
• INTRODUCTION
• BASIC PRINCIPAL OF PLCC
• SIGNALS FOR PLCC
• COMPONENTS
• PLCC STATION
• BLOCK DIAGRAM OF
CIRCUIT
• BASIC COUPLING
ARRANGEMENT
• MAINTAINENCE AND
FAULT TRACKING
• ADVANTAGE
• LIMITATIONS
• CONCLUSION

3. TRAINING OVERVIEW
 Name Of Industry : Rajasthan Rajya Vidyut Prasaran Nigam
Limited
 Location: 220KV GSS PREMISES, RIICO INDUSTRIAL
AREA, BHARATPUR
 Reporting Officer: A. K. MITTAL
 Duration of training : 3rd June to 18th July, 2014
 Department of training :Electronics & Communication

4. INTRODUCTION
 PLCC is the method of transmitting information
using power network.
 Its equipment are used for point-to-point
communication over high voltage power lines
 It’s equipments are used to send/receive
speech/data/teleprotection signals.
 It’s the most economical and reliable method of
communication for medium or long distance.

5. BASIC PRINCIPAL OF PLCC
 The telephone communication system cannot be
directly connected to the high voltage lines so,
we use suitably designed coupling devices for
communication.
 These usually consist of high voltage capacitor
used in conjunction with suitable line matching
unit (LMU) for matching the impedance of line
to that of the coaxial cable connecting the unit
to the PLC transmiter-receiver equipment.

6. SIGNALS FOR PLCC
The signal that can be transmitted over the PLCC
include
 Speech signal (300-2000Hz )
 Data signal (2000-3000Hz)

7. Components
• PLCC station
• Line matching Unit
• CVT/CC
• Earth Switch
• Lightening Arrestor
• Wave Trap
• Co axial Cable
7
EPAX
RF carrier
(40-500kHz)
Power Line
(50Hz)
C.C
RTU
L.T
PLCC TERMINAL

8. PLCC station
• It is the station where (modulation)Transmission ,
Receiving (Demodulation ) , Amplification and
Filtration are performed.
• Transmitter :
8

9. Receiver :

10. CVT/CC
• It is Control Voltage transformer/ Coupling capacitor.
• This is used for blocking the high voltage entering
to the PLCC equipment.
Earth Switch
• This is used at the time of maintenance of LMU.

11. Lightening Arrestor
• Used to protect the system from the
damaging effect of lightening.
• It works as an insulator between light
and the power line.
Co axial Cable
• This is used for inter connection
between PLCC & L.M.U for carrying the
high frequency signal.

12. Line Matching Unit
The out-put of PLCC is connected to the matching unit
before the power lines to achieve the proper impedance
matching and protection in between PLCC Equipments
and power line.
Module Cabinet

13. Wave Trap
• Consists of a number choke
coils connected in series.
• It is connected in series with the
power line and prevents carrier
current from
entering to the power
equipment.
• Offer negligible impedance to
power frequency & high
impedance to carrier frequency.
PLC signal
Blocking
HV Line
Substation
Power
energy
PLC
Signal

14. Block diagram 0f Circuit

15. BASIC COUPLING ARRANGEMENT
 The power frequency and radio frequency currents are
sorted by this arrangement .
 Carrier currents are prevented to enter station bus by
wave trap & power frequency current is blocked by
coupling capacitor, from the PLC equipment.
 Hence we get power current at the bus & carrier current
at PLC equipment.

16. BATTERY CHARGER
• PLCC work on rectified AC or main supply, when supply
goes off, we make use of a device for proper functioning
of PLCC called battery charger.
• This is the device that provide supply to the PLCC
equipment for uninterrupted working.
• It provide DC to the panel by battery.
16

17. Maintenance & Fault Tracking
• FAULT ANALYSIS
In fault analysis the faulty devices are checked in
this serial or manner:-
1. Telephone or tale operation signal
2. Cabling low frequency circuit or DC power supply
3. PLC equipment
4. HF transmission path

18. MAINTAINANCE AND FAULT TRACING
PROCEDURE
1. The control circuit boards should be inserted far
firmly.
2. The charger should be switch off once in every
month.
3. The battery terminal should be connected first and
the AC input after that.
4. All mounting bolts should be checked before
energizing.

19. 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.
 Increased reliability.
 Lower attenuation over long distance.
 Implementation cost is reduced.

20. Limitations
 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 telephone lines.

21. Key learning
• PLCC is mainly used for telecommunication, tele-protection
and tele-monitoring between electrical
substations 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.

22. CONCLUSION
The Training was based on communication over
existing power line.

23. ANY QUERIES ?