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Power line communication technologies in smart grids Chapter 4 155

4.5.2 BB PLC regulations
In Europe, EN 50561-1 standard [92] was accepted in 2012, which describes
transmission limits and measurement methods for indoor BB-PLC systems
operating over LV power networks in the frequency range 1.6065–30 MHz.
This standard separately considers AC mains power, PLC ports, and telecom-
munication networks. Following the EN 50561-1, the EN 50561-3 is released
for frequencies between 30 and 87.5 MHz in 2016 [93]. The EN 50561-1
requires a cognitive frequency exclusion operation that constitutes several
notches in the pass band if a broadcast service is determined. The EN
50561-2 aims to present specifications for outdoor BB-PLC but it is not yet
completed.
In the United States, the Code of Federal Regulations, Title 47, Part 15,
arranges both indoor and outdoor BB-PLC in the range of 1.705–80 MHz. In
addition, it specifies limits for both conducted and radiated emissions. The par-
ticular radiation limits are presented for PLC systems in two parts. The first one
covers frequencies between 1.705 and 30 MHz while the second one is for the
frequencies between 30 and 88 MHz. The conversion of radiation limits into the
PSD values is performed through a coupling factor that may depend on many
parameters such as wiring, topology, and characteristics of power grid.
The BB PLC systems in Japan are only applicable for in-home applications.
Therefore, the BB-PLC systems are designed to operate frequencies between 2
and 30 MHz in Japan [94]. On the other hand, emission limits of common mode
currents are defined in two parts where the first one is valid for 2–15 MHz and
the second one is for 15–30 MHz bands.

4.6 Case study PLC applications for smart grids

In order to provide case study examples of PLC applications, this section pre-
sents several outdoor PLC applications performed for remote monitoring of
renewable energy sources (RESs). The section introduces two PLC applications
reported by the authors of the book [5, 8]. The observing, metering and man-
agement processes are essential for renewable energy systems similar to the
SG applications of conventional power grids. In the first case study, remote
monitoring requirements of the RESs are investigated for solar microgrid sys-
tems [8]. The aim of this case study is to eliminate monitoring costs since the
power lines are not only used to deliver electricity, but also are exploited to
transmit several parameters of loads located at the back-end of the modeled
solar microgrid. The block diagram of designed microgrid structure containing
generation, energy conversion, transmission, distribution and monitoring sec-
tions is depicted in Fig. 4.14. The DC-AC energy conversion system of this
model is composed of solar power plant and multilevel inverter (MLI) system.
While the solar plant contains three separate solar plants with perturb and
observe maximum power point tracking (P&O MPPT) system, the multilevel