IEC/IEEE 60255-118-1:2018

IEC/IEEE 60255-118-1 ®
Edition 1.0 2018-12
INTERNATIONAL
STANDARD
colour
inside
Measuring relays and protection equipment –
Part 118-1: Synchrophasor for power systems – Measurements

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IEC/IEEE 60255-118-1 ®
Edition 1.0 2018-12
INTERNATIONAL
STANDARD
colour
inside
Measuring relays and protection equipment –

Part 118-1: Synchrophasor for power systems – Measurements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.70 ISBN 978-2-8322-6172-9

– 2 – IEC/IEEE 60255-118-1:2018
© IEC/IEEE 2018
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 10
2 Normative references . 10
3 Terms, definitions, and abbreviated terms . 10
3.1 Terms and definitions . 10
3.2 Abbreviated terms . 11
4 Synchrophasor measurement . 12
4.1 Input and output quantities . 12
4.2 Power system signal . 12
4.3 Measurand definitions . 13
4.3.1 Synchrophasor phase angle. 13
4.3.2 Synchrophasor measurand . 13
4.4 Frequency measurand definition . 13
4.5 Rate of change of frequency measurand definition . 14
4.6 Measurement time synchronization . 14
5 Measurement compliance evaluation . 14
5.1 PMU measurement capability . 14
5.2 Measurement evaluation . 14
5.2.1 Synchrophasor measurement evaluation . 14
5.2.2 Frequency and ROCOF measurement evaluation . 15
5.2.3 Measurement response time and delay time . 15
5.2.4 Overshoot and undershoot . 16
5.2.5 Measurement reporting latency . 18
5.2.6 Measurement and operational errors . 18
5.3 Measurement reporting . 19
5.3.1 General . 19
5.3.2 Reporting rates . 19
5.3.3 Reporting times . 19
5.4 Measurement compliance . 19
5.4.1 Performance classes . 19
5.4.2 Compliance verification . 20
6 Measurement compliance test and evaluation . 20
6.1 Testing considerations . 20
6.2 Reference and test conditions . 21
6.3 Steady-state compliance . 21
6.4 Dynamic compliance – Measurement bandwidth . 24
6.5 Dynamic compliance – Performance during ramp of system frequency . 27
6.6 Dynamic compliance – Performance under step changes in phase and
magnitude . 29
6.7 PMU reporting latency compliance . 30
7 Documentation . 31
Annex A (informative) Time tagging and dynamic response . 32
A.1 Dynamic response . 32
A.2 Time tags . 32
A.3 Magnitude step test example . 34

© IEC/IEEE 2018
A.4 PMU time input . 35
Annex B (informative) Parameter representation and definition application examples . 37
B.1 General . 37
B.2 Representing non-stationary sinusoids . 37
B.3 Introduction of definition application examples . 38
B.3.1 General . 38
B.3.2 Example 1: steady-state at nominal frequency . 38
B.3.3 Example 2: steady-state and constant off-nominal frequency . 38
B.3.4 Example 3: oscillation of the phase and amplitude of the power signal . 39
B.3.5 Example 4: constant, non-zero rate of change of frequency . 40
B.4 Reconstruction of the power system sinusoidal signal from the
synchrophasor . 41
Annex C (informative) PMU evaluation and testing . 42
C.1 General . 42
C.2 TVE measurement evaluation . 42
C.3 Phase-magnitude relation in TVE and timing . 43
C.4 Evaluation of response to stepped input signals . 45
C.5 Harmonic distortion test signal phasing . 47
C.6 ROCOF limits . 47
C.6.1 General . 47
C.6.2 Derivation . 48
C.7 PMU reporting latency. 49
Annex D (informative) Reference signal processing models . 50
D.1 General . 50
D.2 Basic synchrophasor estimation model . 50
D.3 Timestamp compensation for low-pass filter group delay. 51
D.4 Positive sequence, frequency, and ROCOF . 52
D.5 P Class reference model for phasor . 53
D.6 P class filter details . 53
D.7 M class reference model for phasor . 55
D.8 Data rate reduction model . 57
D.9 Trade-offs in the reference model . 58
D.9.1 Immunity to off-nominal components, reporting latency and time
alignment . 58
D.9.2 Response time and the accuracy of synchrophasors, frequency and

ROCOF measurements . 59
Annex E (informative) Synchrophasor measurement using sampled value input to
PMU . 61
E.1 General . 61
E.2 Creation of sampled values . 61
E.3 Sources of synchrophasor error when using sampled values . 62
E.4 Performance . 62
E.4.1 General . 62
E.4.2 Steady-state performance considerations . 62
E.4.3 Dynamic performance considerations . 63
E.4.4 Latency. 63
E.5 Proposed changes to performance requirements . 64
Annex F (informative) Suggested subset of tests for PMU evaluation under
environmental influences .
...