Alstom MiCOM P846, Техническое руководство

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P846/EN OP/D Operation
(OP) 5-6
MiCOM P846
OP
s its
capability to provide signal components at spectral frequencies other than the fundamental
and its harmonics. More specifically, its benefits are:
1. It is possible to make the Kalman filter self-tuned to the fundamental frequency without
any hardware modification.
2. The Kalman filter allows to filter pre-selected resonant non-harmonic frequencies. This
is beneficial in power networks characterized by non-harmonic phenomena such as
series-compensated transmission systems subject to sub-synchronous resonances.
3. It can provide the signal components at spectral frequencies other that the
fundamental and its harmonics. The Kalman filter has an effective built-in self-
diagnosis tool, making use of both the negative sequence component at fundamental
and the excess electromagnetic resonances that may transiently appear when a line is
opened at both ends.
The principle of the Kalman-filter based harmonic analyzer implemented in the DLO is shown
“p”
harm
n-
harm
1.3.2 Kalman filtering stage
The advantage and superiority of this filtering technique in the present application i
on figure 3. The incoming signal is filtered according to a model of the signal. A set of
onic, “q” non-harmonic phasors and the dc component are generated at the output. In
the actual model used for the DLO, five harmonics (including the fundamental) and two no
onics terms were incorporated. The resulting frequency response is shown on figure 4.
X
1
(k) = X
f
(k)
Y
1
(k)
Y
q
(k)
Residuals
X
3
(k)
X
p
(k)
X
dc
(k)
X
2
(k)
Y
2
(k)
Y
3
(k)
Harmonics
Non-harmonics
System
Fundamental
frequency
ω
c
(k
)
Z
(k
)
Incoming signal
Kalman-Filter
Based
Harmonic
Analyser
Figure 3: Principle of the self-tuned Kalman-filter with p harmonics and q
non-harmonics spectral lines