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Smart metering and smart monitoring systems Chapter 2 91

measurement that is assisted with reliable communication and monitoring sys-
tems to perform real time control and management operations. There are several
devices such as digital fault recorder (DFR) are developed to realize protection
tests and control of protection relays [21]. There are two specified standards
exist for PMU data communication that are IEEE C37.118 and IEC 61850.
Although IEC 61850 standard is developed for substation monitoring applica-
tions, it is accepted as a key standard for real time data acquisition requirements.
The C37 standard includes a set of definitions for synchronized phasor measure-
ment systems including synchrophasor, frequency, and rate of change of fre-
quency (ROCOF) measurements. Moreover, it describes time tagging and
synchronization requirements for measurement of mentioned quantities. The
precision time protocol of GPS communication is defined by IEEE C37.238
while IEEE C37.118 describes phasor measurements. On the other hand, IEEE
C37.242 provides a set of definition on PMU calibration, test and installation
procedures. PMU and synchrophasor data transfers are also defined by IEEE
C37.118 standards, IEEE C37.244 defines PDC requirements, and IEEE
C37.111 describes common format data exchange requirements in PDC data
storage applications.
A detailed list of WAMS applications and their PMU and communication
resource requirements are shown in Table 2.4. The PMU requirements are clas-
sified according to low, medium, and high in terms of numbers while commu-
nication requirements are evaluated into three groups considering their resource
requirements [22]. The list presents specified and widely used PMU applica-
tions in smart grid infrastructure.

TABLE 2.4 WAMS applications and requirements
PMU Communication
requirements requirements WAMS application type
Low Low Steady state estimation
Low Low Thermal line monitoring
Low Medium Phase and frequency
monitoring
Low Medium Event monitoring and detection
Low Medium Oscillation monitoring and
detection
Medium Low Dynamic parameters
estimation
Medium Low Post event analysis
Medium Medium Voltage stability monitoring
Continued