Closing Angle Calculator - Hitachi Relion 650 Series Technical Manual

Section 12
Monitoring
Validity of Estimated Residual Fluxes
After taking the snapshot, TRAFOSWT performs a plausibility check on the estimated residual fluxes.
The calculated flux after de-energization (taken at the FluxSnapshot setting) should not exceed the
peak of the flux before de-energization. If this condition gets violated in any phase, a binary output
INVFLUX is activated. If the condition doesn't get violated, a binary output VALIDSTGY is activated.
The calculated residual flux values are still published in such a condition.
In case of the activation of VOLTGON binary input, the function retains the previous state of
INVFLUX output whereas the output VALIDSTGY is reset to 0.
Table 288: Activation of VALIDSTGY and INVFLUX
ǀRESFLUXǀ>Φ
where, Φ
These outputs remain active until the next activation of OPNDETECT. Before the first transformer de-
energization evaluated by this function and with no retained values, both binary outputs are 0. Also,
when the transformer is energized, that is, VOLTGON = 1, INVFLUX retains its previous state,
whereas VALIDSTGY is reset to 0.
12.20.7.3

Closing Angle Calculator

Based on the residual fluxes estimated in
target making angles for controlled energization of the transformer. Since the residual fluxes
estimated in the mentioned section are based on the limb voltages, the function first needs to map
these fluxes from the limb voltages onto the source voltages based on which the switching angles
are defined. The necessary calculations are predefined in the function for each specific winding
configuration, which is selected through the TrafoType setting as per
for each phase are obtained by performing a sine inverse on the respective estimated residual fluxes.
Table 289: Transformer types
TrafoType
Yn non-coupled
Yn coupled
Y
D1
D11
D7
Table continues on next page
326
If there is a chance that the original source of the load voltage signal may change in
service (for example, through 3PHSELECT), the application should ensure that no
integration is triggered during the transition period. In the mentioned example, this
can be achieved by feeding the BLOCKOUT signal of 3PHSELECT to the
BLOCKINT input of TRAFOSWT. If any integration is ongoing, it will be completed
before BLOCKINT takes effect. Refer to
VOLTGON
peak
Y 0
N 0
X X
X 1
is the peak of the dynamic flux in the individual phase.
peak
Switched Winding Type with
neutral grounding
Star with grounded neutral
Star with grounded neutral
Star with ungrounded neutral
Delta
Delta
Delta
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Section 12.20.7.7
FALLBACK VALIDSTGY
0
0
1
X
Section 12.20.7.2.1, TRAFOSWT calculates the ideal
Electrically or
magnetically coupled?
No
Yes
No
Yes
Yes
Yes
1MRK 511 557-UEN Rev. A
for more details.
GUID-46D3CC5E-3414-43FD-8971-B891CEBF3F77 v1
INVFLUX
1 0
0 1
0 Previous state
0 Previous state
GUID-B95F11B8-FE4F-48C7-AEC0-AA09CA28441F v1
Table 289. The making angles
Phase Angle
-
-
-
+30° (D1)
-30° (D11)
-150° (D7)
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