Alstom Reason RPV311, Technical Manual

Page: 166 / 350

Chapter 6
– Records
RPV311
166 RPV311-TM-EN-6
A Fourier transform is used to obtain all frequency components of the input signal up to the 50
𝑡ℎ
order.
The values obtained at every measuring window are aggregated over
𝑇
vs
= 3 s.
Values resulting of the
𝑇
vs
= 3 s aggregation are aggregated a second time over
𝑇
sh
= 10 min using
classifiers. The result is the cumulative probability for each harmonic component of the input signal.
For each harmonic component of the input signal, the value that does not exceed the
𝑝
= 1, 10, 50, 90, 95,
and 99 % percentiles in the
𝑇
sh
time interval is recorded.
5.3 FLICKER
Flicker is computed for phases A, B, and C for up to six voltage circuits. The algorithm used conforms to IEC
61000-4-15:2003.
The aggregation time interval is 10 minutes in the Pst Flicker or Plt Flicker 2 hours, synchronized to UTC
minute rollover. The timestamp refers to the end of the averaging window.
It generates one record per day.