Setting Guidelines - Hitachi Relion 670 Series Applications Manual

Section 10
Frequency protection
However, the IEEE/ANSI C37.106-2003 standard "Guide for Abnormal Frequency Protection for Power
Generating Plants" provides some examples where the time accumulated within each frequency range is
as shown in Figure 76.
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60
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56
0.01
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60
58
56
0.01
IEC13000258 V1 EN-US
Figure 76:
Another application for the FTAQFVR (81A) protection function is to supervise variations from rated
voltage-frequency. Generators are designed to accommodate the IEC 60034-3:1996 requirement of
continuous operation within the confines of their capability curves over the ranges of +/-5% in voltage
and +/-2% in frequency. Operation of the machine at rated power outside these voltage-frequency limits
lead to increased temperatures and reduction of insulation life.
10.4.3

Setting guidelines

Among the generator protection functions, the frequency time accumulation protection FTAQFVR (81A)
may be used to protect the generator as well as the turbine. Abnormal frequencies during normal
operation cause material fatigue on turbine blades, trip points and time delays should be established
based on the turbine manufacture's requirements and recommendations.
Continuous operation of the machine at rated power outside voltage-frequency limits lead to increased
rotor temperatures and reduction of insulation life. Setting of extent, duration and frequency of
occurrence should be set according to manufacture's requirements and recommendations.
Setting procedure on the IED
The parameters for the frequency time accumulation protection FTAQFVR (81A) are set using the local
HMI or through the dedicated software tool in Protection and Control Manager (PCM600).
166
Prohibited Operation
Continuous operation
Restricted Time Operation
0.1 1 10 100
Time (Minutes)
Prohibited Operation
Restricted Time Operation
Continuous operation
Prohibited Operation
Restricted Time Operation
0.1 1 10 100
Time (Minutes)
Examples of time frequency characteristics with various frequency band limits
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62
Restricted Time Operation
Continuous operation
60
Restricted Time Operation
58
56
1000 0.01 0.1 1
Time (Minutes)
Prohibited Operation
62
Continuous operation
60
58
Restricted Time Operation
56
1000 0.01 0.1 1
Time (Minutes)
1MRK511407-UUS Rev. N
Prohibited Operation
Prohibited Operation
10 100 1000
Prohibited Operation
10 100 1000
IEC13000258-1-en.ai
GUID-62C6D764-CAF2-4C2F-B91A-EBC611987D72 v3
Phasor measurement unit RES670
Application manual