Page 63 - From Smart Grid to Internet of Energy

Introduction to smart grid and internet of energy systems Chapter 1 49

FIG. 1.14 Hierarchical organization of PMU and PDCs.

datasets generated by many PMUs and lots of substation and control center
PDCs. The super PDCs perform PMU measurement in a large application group
including wide area monitoring system (WAMS), monitoring, EMS, and
SCADA applications. It can store collected data for long times due to its large
data storage capability [4]. The hierarchical organization of PDCs and PMUs is
shown in Fig. 1.14 where they are configured in star topology. The substation
PDCs cannot provide technically expected efficiency when PMUs in a substa-
tion exceed 100 [2].
The collected data from substations are transmitted to control center to
perform several decision-making and operation processes. The featured appli-
cations include monitoring power system conditions and faults, analyzing vul-
nerability of utility grid to demand response and DSM situations, and automatic
gain control. The PMU based WAMPAC system combined advantages of
SCADA, EMS and WAMS.

1.3.3 Smart meters
The smart metering is one of the essential operations in smart grid infrastruc-
ture. Smart meters are improved versions of conventional power meters that are
developed after AMR and AMI improvements. The smart meters are equipped
with advanced ICT interfaces making them quite sophisticated and detailed. In
addition to metering features, smart meters are capable to calculate several
parameters as power factor or THD and to predict power consumption at par-
ticular intervals. Besides its remote-control features used by MDMS, it also
allows users to remote monitoring and remote control for their home energy
management systems. The smart meters are also defined as smart socket due