Siemens Transformer Technology Seminar Stray Flux...
Transcript of Siemens Transformer Technology Seminar Stray Flux...
siemens.com/answers© Siemens AG 2016 All rights reserved.
Siemens Transformer Technology SeminarStray Flux Control
Pomona CA, May 24-25, 2016
Siemens AG – Transformers
© Siemens AG 2016 All rights reserved.
Stray Flux Control
Siemens Transformer Technology SeminarStray Flux Control
Page 2
© Siemens AG 2016 All rights reserved.
Siemens Transformer Technology SeminarStray Flux Control
Why highlight Stray Flux Control
Page 3
• Keeping products at the forefront of development
• Increased power transmission needs have led todetailed consideration of losses
• SIEMENS has had a special focus on stray fluxcontrol for more than 30 years
• Committees and publications on stray flux control
• ICEM, CEFC, Compumag, ISEF, IGTE Symposium
• Compel, IEEE Trans. On Industry Application, IEEETrans. on Magnetics
© Siemens AG 2016 All rights reserved.
0
50
100
150
200
250
300
1960 1970 1980 1990 2000 2010 2020
Stra
ylo
ss(k
W)
Production year
tap +
tap 0
tap -
Siemens Transformer Technology SeminarStray Flux Control
Page 4
Powerful computational tools
• Detailed analysis of complex geometries
• CAD tools and in-house developedpreprocessors
• Gives a quick overview and allowsidentification of eddy losses in structuralsteel parts
Committed to decreasing losses
• Illustration of the stray loss decrease
• Comparing similar 150 MVA
• Long term advances by adopting newtechnologies
• Customer advantage by decreasedoperating costs
© Siemens AG 2016 All rights reserved.
Siemens Transformer Technology SeminarStray Flux Control
Current practice and development
Page 5
• Advantages by decreased stray flux losses
• Higher efficiency
• Smaller transformers may be used
• Reduced operating costs
• Safer operation of transformers with strayflux control:
• Avoids local overheating
• Avoids accelerated aging of oil and gasbubble generation
• Appearance of stray flux losses
• Windings, tank, clamping plates, tie barsand yokes
• The crucial step to loss-control
• Calculation of the stray flux distribution
• Experience and ongoing research
• Fast solution of complex problem
• Validated and reliable solutions
Stray flux in transformers Benefits of controlling stray flux
© Siemens AG 2016 All rights reserved.
Siemens Transformer Technology SeminarStray Flux Control
Page 6
State of the art software and capabilities
• Nonlinear, anisotropic materials
• Eddy current and hysteresis losses
• Static, time-harmonic (with nonlinearity),transient, transient with DC bias, coupledcomputations
Comparison of the losses in transformers
• Larger units require special knowledge
• The Siemens approach guarantees costeffective and safe solution
0%10%20%30%40%50%60%70%80%90%
100%
40 150 200 400 500 800Power rating (MVA)
Ohmic loss Eddy loss in windings Stray loss
Percentage of stray losses in load losses on units of differentpower ratings
© Siemens AG 2016 All rights reserved.
Siemens Transformer Technology SeminarStray Flux Control
Page 7
Continuous testing and validation
• Comparison of the calculated andmeasured temperature
• Verification of the results and comparisonagainst measurements
Optimization of designs
• Check all critical points
• Understanding the stray flux distribution
• Detailed 3D analyses
• Optimize the shielding solution
• Develop a special shield arrangement
© Siemens AG 2016 All rights reserved.
Siemens Transformer Technology SeminarStray Flux Control
We can offer:
Page 8
• Access to state of the art software to provide accurate resultsand in-house preprocessors developed to reduce the timetaken to conduct an analysis
• Ability to calculate the stray flux change due to phenomenasuch as geomagnetically induced currents to ensure secureperformance of the transformer during operation
• Experience in reduction of overall losses while finding theoptimal cost efficiency to keep operating costs as low aspossible for our customers
• Results verification through cross-checking calculationsagainst measurements
Detailed stray flux loss simulation models
1200 MVA, 242/24 kV Transformer - 3D FEM models lead to perfect calculation-results of real temperature effects as verified by thermal scanning
© Siemens AG 2016 All rights reserved.Page 9
Siemens AG - TransformersContact
Martin StösslHead – Global Technology CentreE T TR LPT GTC
Elingasse 38160 WeizAustria
Phone: +43 (51707) 71417Mobile: +43 (664) 80117 71417
E-mail:[email protected]
Siemens.com/transformers