Copyright © Siemens AG Energy Sector CIGRE 2010 “Seismic Behavior of Siemens Circuit Breakers during the Earthquake on 27 February 2010 in Chile ” October 19th, 2010
Copyright © Siemens AGEnergy Sector
CIGRE 2010 “Seismic Behavior of Siemens Circuit Breakers during the Earthquake on27 February 2010 in Chile ”
October 19th, 2010
page 2 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Siemens circuit breaker sold by factory Berlin andpercentage of CB with seismic requirements
In the years 2005-2010 round about 22 000 circuit breaker (life tank and dead tank ) have been delivered from the Siemens factory Berlin.
25% (5500) had seismic requirements from different standards (from 0.3g ZPA – mostly 0.5g ZPA).
Until the severe earthquake on 27 February 2010 no Siemens circuit breaker did fail caused by seismic action.
page 3 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Brief history of seismic qualification of Siemens circuit breakers
-from 1990 – seismic tests with acc. time history; before 1990 seismic testswith sine beats
-from 1998 – dynamic calculations; FEM ADINA; before 1998 static calculations only
-from 2002 – dynamic analysis with ANSYS Classic
-from 2009 - dynamic analysis with ANSYS Workbench
page 4 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Some aspects of the Standards IEEE 693,ETG and IEC 62271-300
IEEE ETG IEC
-calculation not excepted 169 kV - -and above
-switching during seismic test x - -
-sine beat x x -
-damping ratio for calculation 2% x x xif not justified other values
page 5 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Comparison of calculation and test
Installation of test equipment
page 6 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Comparison of calculation and test
Natural frequencies
calculated tested location
X 4,9 Hz (- 6%) 5,2 Hz Bushing8,7 Hz minor frequency9,7 Hz minor frequency
19,1 Hz (+20%) 15,9 Hz Frame26,4 Hz minor frequency
Y 4,8 Hz (- 9%) 5,3 Hz Bushing15,5 Hz (+26%) 12,3 Hz Frame
23,1 Hz minor frequency
26,4 Hz minor frequency
Z not detected 15,8 Hz Control cabinet25,1 Hz minor frequency29,7 Hz minor frequency33,1 Hz minor frequency
Dire
ctio
n
page 7 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Mises stress plot
test results 100%
Comparison of calculation and test
133%
116% 207%
93%
91%
calculated results:
page 8 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
frequency: 100% about 140%
Unprestressed and pre-stressed modal analysis with response spectrum method
displacement: 100% about 50%
stress post insulator: 100% about 70%
F 2000 N0 N
(IEC 62271-300; 0,5g and 5% damping ration)
page 9 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
How many modes are necessary?
calculation with 3 modes
stress post insulator: 100% about 96%
calculation with only 1 mode
page 10 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Influence of cable connection
(example from literature)
slack span:case 1 - 110 mm
slack span:case 2 – 490 mm
page 11 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Influence of foundation and steel structure
seismic tests with two different steel structures showed a different of 40% in the bending moment of a life tank CB post insulator
frequency
acce
lera
tion
0,5g ZPA
dampers??
page 12 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Some spectrums from Santiago de Chile5 % damping (acceleration not rectified)
critical frequency of about 2 Hz
page 13 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Siemens circuit breaker in Chile
Behavior of Siemens circuit breakers during 27 of February 2010
-3AP3 FI 550 kV � no damage
-3AP1 FI 245 kV � damage on the mechanism housingportland cementation?
-3AP1 FG 245 kV � damage on some porcelains
-3AP1 DT FI 245 kV � no damage
-voltage level under 245 kV � no damage
page 14 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
3AP3 FI 550 kV with friction dampers
no damage occurred
page 15 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
3AP1 FI 245 kV
damage on:-the mechanism housing-portland cementation?
page 16 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
3AP1 FG 245 kV
-dynamic calculation did show a safety factor of more than two according the ETG 1.020
-cable connection on the terminals seems to be okay
-Why the porcelain broke?
-Frequencies and level of seismic motion?
page 17 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Seismic analysis qualification by FEMin the past and present
ANSYS “Classic” ANSYS “Workbench”
page 18 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Remedial work
The reinforcement of the corners of the mechanism housingFoto FE mesh
page 19 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Comparison of calculationmechanism housing
without reinforcment with reinforcement
Mises stress 100% Mises stress about 50%
page 20 October 19 th, 2010Copyright © Siemens AG
Energy SectorUlf Heinrich
Future work
-use more accurate FE-Models (using the models directly from CAD-program in order to prepare the geometrical model)
-reinforce the mechanism housing with ductil steel parts below the steel frame
-perform a seismic test according ETG A.0.20 for the 3AP1FI 245 kV
-where necessary reinforce the porcelains
-use dampers where necessary