ABB Relion REG670, Applications Manual

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IEC140000121-2-en.vsd
IEC140000121 V2 EN
Figure 42: Multiple instances of BINARYREPORT blocks
6.2.3 Operation principle
The Phasor Measurement Unit (PMU) features three main functional principles:
• To measure the power system related AC quantities (voltage, current) and to
calculate the phasor representation of these quantities.
• To synchronize the calculated phasors with the UTC by time-tagging, in order to
make synchrophasors (time is reference).
• To publish all phasor-related data by means of TCP/IP or UDP/IP, following the
standard IEEE C37.118 protocol.
The C37.118 standard imposes requirements on the devices and describes the
communication message structure and data. The PMU complies with all the standard
requirements with a specific attention to the Total Vector Error (TVE) requirement.
The TVE is calculated using the following equation:
2 2
2 2
r r i i
r i
( X ( n ) X ) ( X ( n ) X )
TVE
X X
- + -
=
+
GUID-80D9B1EA-A770-4F50-9530-61644B4DEBBE V1 EN
(Equation 14)
where,
X
r
(n) and X
i
(n) are the measured values
X
r
and X
i
are the theoretical values
In order to comply with TVE requirements, special calibration is done in the factory
on the analog input channels of the PMU, resulting in increased accuracy of the
measurements. The IEEE C37.118 standard also imposes a variety of steady state and
dynamic requirements which are fulfilled in the IED with the help of high accuracy
measurements and advanced filtering techniques.
Section 6
1MRK 502 071-UEN -
Wide area measurement system
110 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual