Page 126 - From Smart Grid to Internet of Energy

110 From smart grid to internet of energy

3.4 Field area networks (FANs)
In power distribution level of the SG, high voltage electricity is transformed into
low voltage electricity by using step-down transformers in order to fulfill the
needs of commercial, industrial and home users [8, 21]. The transformers
can also insulate faults and are utilized to provide a voltage regulation point
as well as voltage transformation process. A FAN is responsible to ensure con-
nectivity of smart devices in substations, distribution and transmission grids.
Smart devices that may be used in FAN can be power line monitors, voltage
regulators, breaker controllers, capacitor bank controllers, smart transformers,
data collectors, and so on. In order to advance quality and reliability of power
systems, these devices are employed to rapidly detect irregularities and failures.
In the SG distribution domain, sufficient number of Remote Terminal Units
(RTUs) along with Phase Measurement Units (PMUs) and IEDs will be essen-
tial to execute several substation automation functions. In addition, the distri-
bution feeders can be exploited as a point of common coupling (PCC) for the
connected DERs and micro-grid components. In order to ensure power delivery
to the customer premises, the distribution feeders utilize power lines, cable
poles and towers. In addition, deployment of wireless sensors along with these
components would be essential to improve distribution supervisory applica-
tions. The key task of a FAN is to ensure exchange of information among
numerous monitoring, control and protection applications available in between
the feeder level equipment, distribution substations and applications.
A connection between backhaul of a utility service and a particular service
stage of the distribution grid can be realized through the FAN communication
network. Typically, a FAN presents the communication connections among the
substation stage and customer stage by exploiting several collector combina-
tions, access points and data concentrators. FAN channels having extremely
robust, stable and low bandwidth features connect sensors/data collectors with
a centralized GW. International Electromechanical Commission (IEC) 61850
standard is commonly employed for DA and substation within the FAN, which
offers interoperability among IEDs and machine-to-machine (M2M) communi-
cations. Latency demands of the FANs for crucial applications may change
from 3 to 10 ms according to the IEC 61850 standard [21, 22].
The applications utilizing the FAN schemes can be grouped into two cate-
gories as field based and customer based applications [11]. The first group,
which has connection with sensors, transmission lines, voltage regulators and
so on, consists of outage management system (OMS), supervisory control
and data acquisition (SCADA) applications, distributed energy resource
(DER) monitoring and control. The second group, which has connection with
end-users such as houses, buildings, industrial users and so on, cover AMI, DR,
load management system (LMS), metering data management system (MDMS).
Both types of these applications functioning in the distribution domain possess
several important needs. For instance, customer based applications call for