CIGRE Seismic Behavior of Siemens Circuit Breakers during the Earthquake on 27 February 2010 in Chile. October 19th, 2010

Transcription

1 CIGRE 2010 Seismic Behavior of Siemens Circuit Breakers during the Earthquake on 27 February 2010 in Chile October 19th, 2010

2 Siemens circuit breaker sold by factory Berlin and percentage of CB with seismic requirements In the years round about 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 2 October 19 th, 2010

3 Brief history of seismic qualification of Siemens circuit breakers -from 1990 seismic tests with acc. time history; before 1990 seismic tests with sine beats -from 1998 dynamic calculations; FEM ADINA; before 1998 static calculations only -from 2002 dynamic analysis with ANSYS Classic -from dynamic analysis with ANSYS Workbench page 3 October 19 th, 2010

4 Some aspects of the Standards IEEE 693, ETG and IEC 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 x if not justified other values page 4 October 19 th, 2010

5 Comparison of calculation and test Installation of test equipment page 5 October 19 th, 2010

6 Comparison of calculation and test Direction Natural frequencies calculated tested location X 4,9 Hz (- 6%) 5,2 Hz Bushing 8,7 Hz minor frequency 9,7 Hz minor frequency 19,1 Hz (+20%) 15,9 Hz Frame 26,4 Hz minor frequency Y 4,8 Hz (- 9%) 5,3 Hz Bushing 15,5 Hz (+26%) 12,3 Hz Frame 23,1 Hz minor frequency 26,4 Hz minor frequency Z not detected 15,8 Hz Control cabinet 25,1 Hz minor frequency 29,7 Hz minor frequency 33,1 Hz minor frequency page 6 October 19 th, 2010

7 Comparison of calculation and test Mises stress plot test results 100% calculated results: 93% 91% 133% 116% 207% page 7 October 19 th, 2010

8 Unprestressed and pre-stressed modal analysis with response spectrum method (IEC ; 0,5g and 5% damping ration) frequency: 100% about 140% 0 N F 2000 N displacement: 100% about 50% stress post insulator: 100% about 70% page 8 October 19 th, 2010

9 How many modes are necessary? calculation with 3 modes calculation with only 1 mode stress post insulator: 100% about 96% page 9 October 19 th, 2010

10 Influence of cable connection slack span: case mm slack span: case mm (example from literature) page 10 October 19 th, 2010

11 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 dampers?? acceleration 0,5g ZPA frequency page 11 October 19 th, 2010

12 Some spectrums from Santiago de Chile 5 % damping (acceleration not rectified) critical frequency of about 2 Hz page 12 October 19 th, 2010

13 Siemens circuit breaker in Chile Behavior of Siemens circuit breakers during 27 of February AP3 FI 550 kv no damage -3AP1 FI 245 kv damage on the mechanism housing portland cementation? -3AP1 FG 245 kv damage on some porcelains -3AP1 DT FI 245 kv no damage -voltage level under 245 kv no damage page 13 October 19 th, 2010

14 3AP3 FI 550 kv with friction dampers no damage occurred page 14 October 19 th, 2010

15 3AP1 FI 245 kv damage on: -the mechanism housing -portland cementation? page 15 October 19 th, 2010

16 3AP1 FG 245 kv -dynamic calculation did show a safety factor of more than two according the ETG cable connection on the terminals seems to be okay -Why the porcelain broke? -Frequencies and level of seismic motion? page 16 October 19 th, 2010

17 Seismic analysis qualification by FEM in the past and present ANSYS Classic ANSYS Workbench page 17 October 19 th, 2010

18 Remedial work The reinforcement of the corners of the mechanism housing Foto FE mesh page 18 October 19 th, 2010

19 Comparison of calculation mechanism housing without reinforcment with reinforcement Mises stress 100% Mises stress about 50% page 19 October 19 th, 2010

20 Future work -use more accurate FE-Models (using the models directly from CADprogram 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 page 20 October 19 th, 2010