Page 138 - From Smart Grid to Internet of Energy

122 From smart grid to internet of energy

words, the frequencies below 3 kHz are used by the UNB PLC technologies
where the reachable data rate is around 100 bps. The UNB PLC technologies
that have been exploited metering applications are based on proprietary
solutions.
Narrowband (NB) PLC technologies: These technologies operate at fre-
quencies between 3 and 500 kHz, and the NB PLC systems are composed of
two subcategories called “low data rate (LDR)” and “high data rate (HDR)”.
The NB PLC standards differ from country to country, and the NB frequencies

are specified by European Comit e Europ een de Normalization Electrotechnique
(CENELEC) in Europe, Federal Communications Commission (FCC) in USA,
Association of Radio Industries and Businesses (ARIB) in Japan, and Electric
Power Research Institute (EPRI) in China.

l Low data rate (LDR): LDR NB PLC technologies that use single carrier
modulation schemes are widely preferred for smart metering and indoor
automation applications. Some popular examples of this category are IEC
61334-5 based metering systems, X10 and HomePlug C&C.
l High data rate (HDR): HDR NB PLC technologies can present up to hun-
dreds of kbps data rates by using multicarrier modulation schemes such as
orthogonal frequency division multiplexing (OFDM). Powerline Related
Intelligent Metering Evolution (PRIME) Alliance and G3-PLC Alliance
developed PRIME and G3-PLC, respectively. These industrial specifica-
tions have been recently involved into the ITU-T Recommendations
G.9903 and G.9904.

Broadband (BB) PLC technologies: BB PLC systems operate in a very wide
frequency range from 1.8 to 250 MHz. They employ multicarrier modulation
schemes similar to the HDR NB PLC systems. In addition, this technology
can reach data rates at the level of Mbps since it has been developed for
high-speed indoor applications. The BB PLC technology based devices are
compatible with TIA-1113, IEEE 1901 and ITU-T G.hn standards.
As shown in Fig. 4.2, the PLC technologies can be summarized in terms of
operating frequencies, data rates, mapping schemes, regulations and standards.
Further information for the specifications and standards of UNB PLC, NB PLC,
and BB PLC systems are presented in Section 4.4.

4.2.1 Ultra-narrow band PLC

The first application for load control in the UNB frequencies was the RCS that
was based on unidirectional communication feature with very low data rates.
Other applications are AMR Turtle System and Two-Way Automatic Commu-
nications System (TWACS). While data rate of former system is extremely low
as much as 0.001 bps, data rate of TWACS is maximum at most twice the mains
frequency, i.e., 100 bps in Europe and 120 bps in North America [17].Even