TY - JOUR
T1 - Field Measurement of Frequency and ROCOF in the Presence of Phase Steps
AU - Wright, Paul S.
AU - Davis, Peter N.
AU - Johnstone, Kevin
AU - Rietveld, Gert
AU - Roscoe, Andrew J.
N1 - Funding Information:
Manuscript received July 5, 2018; revised September 13, 2018; accepted November 11, 2018. Date of publication December 11, 2018; date of current version May 10, 2019. This work was supported in part by the EMPIR Programme and in part by the Participating States and the European Union’s Horizon 2020 Research and Innovation Programme. The Associate Editor coordinating the review process was Michael Lombardi. (Corresponding author: Paul S. Wright.) P. S. Wright and P. N. Davis are with the National Physical Laboratory, Teddington TW11 0LW, U.K. (e-mail: [email protected]).
Publisher Copyright:
© 2018 IEEE.
PY - 2019/6
Y1 - 2019/6
N2 - A description of the importance of rate of change of frequency (ROCOF) measurements to the operation of electricity networks is given. The susceptibility of ROCOF measurements to common power system disturbances such as phase steps is described. A measurement campaign to observe ROCOF at multiple locations in an island grid dominated by renewable generation is described and some results are given. These captured ROCOF events are dominated by those associated with phase steps, which occur without significant change to underlying power system frequency. It is concluded that they constitute a 'false' ROCOF event. A new algorithm is presented that attempts to remove the influence of the phase step and reduce the associated ROCOF error such that the reliability of ROCOF measurements can be improved in the presence of phase steps. The algorithm is then applied to some recorded waveform sequences from the island that contains phase steps, and the results are presented. In one example, it is shown that a false ROCOF spike in excess of 100 Hz/s was reduced to less than 5 Hz/s.
AB - A description of the importance of rate of change of frequency (ROCOF) measurements to the operation of electricity networks is given. The susceptibility of ROCOF measurements to common power system disturbances such as phase steps is described. A measurement campaign to observe ROCOF at multiple locations in an island grid dominated by renewable generation is described and some results are given. These captured ROCOF events are dominated by those associated with phase steps, which occur without significant change to underlying power system frequency. It is concluded that they constitute a 'false' ROCOF event. A new algorithm is presented that attempts to remove the influence of the phase step and reduce the associated ROCOF error such that the reliability of ROCOF measurements can be improved in the presence of phase steps. The algorithm is then applied to some recorded waveform sequences from the island that contains phase steps, and the results are presented. In one example, it is shown that a false ROCOF spike in excess of 100 Hz/s was reduced to less than 5 Hz/s.
KW - Frequency measurement
KW - Phasor measurement units (PMUs)
KW - Power system measurements
KW - Rate of change of frequency (ROCOF)
UR - http://www.scopus.com/inward/record.url?scp=85058663934&partnerID=8YFLogxK
U2 - 10.1109/TIM.2018.2882907
DO - 10.1109/TIM.2018.2882907
M3 - Article
AN - SCOPUS:85058663934
SN - 0018-9456
VL - 68
SP - 1688
EP - 1695
JO - IEEE transactions on instrumentation and measurement
JF - IEEE transactions on instrumentation and measurement
IS - 6
M1 - 8573134
ER -