Development of High-Temperature SuperconductingTransformers for Railway Applications
SEMINAR ON- Development of High-Temperature Superconducting Transformers for Railway Applications
PRESENTED BY Mr Amol Namdev Salokhe TEElectrical Engineering GUIDE Mr Prof H MMallad Sir
INTRODUCTION
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
ASSEMBLY AND COOL DOWN
TEST RESULTS
CONCLUSION
REFRENCES
CONTENTS
We describe the high-temperature superconducting (HTS) transformer project run by Siemens The project started in October 1996 and ended in September 2001 The aim of the project was to show the future prospects for superconducting railway transformers To study the principle behavior of such a transformer the authors as a first step designed constructed and tested a nominal single-phase transformer 100 kVA 50 Hz 55 kV11 kV After this was successfully tested we started the design and construction of a single-phase transformer 1 MVA 50 Hz 25 kV14 kV This unit already has the full ratings of a commercial transformer in many respects eg power range nominal voltage 2-limb core with horizontal orientation two secondary windings and an impedance of 25 at nominal current Further innovative features are transposed conductor and a closed cooling cycle with sub-cooled nitrogen The report describes the 1-MVA transformerrsquos detailed design and presents the results of electrical and thermal transformer routine tests (eg measurement of load losses and no-load losses) The conclusion highlights the future perspective of HTS transformers for railway applications
INTRODUCTION
Transformer is a static device which transfer electrical energy from one circuit to another circuit without changing its frequency
Transformer is an heart of substation
WHAT IS THE TRANSFORMER
A Ratings
The single-phase transformer has a nominal frequency of 50 Hz It has two identical LV windings taken toward the outside The HV winding has a nominal voltage of 25 kV and a nominal current of 40 A The LV windings have a nominal voltage of 1389 V and a nominal current of 360 A The nominal impedance voltage is 25
B Core-and-Coil Assembly
The core-and-coil assembly consists of a 2-limb core whereby each limb is wound The winding structures of the two limbs are identical except for the direction of winding The windings are arranged in a doubly concentric layout in the radial sequence LV inside-HV-LV outside The HV windings of the two limbs are connected in parallel
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
SEMINAR ON- Development of High-Temperature Superconducting Transformers for Railway Applications
PRESENTED BY Mr Amol Namdev Salokhe TEElectrical Engineering GUIDE Mr Prof H MMallad Sir
INTRODUCTION
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
ASSEMBLY AND COOL DOWN
TEST RESULTS
CONCLUSION
REFRENCES
CONTENTS
We describe the high-temperature superconducting (HTS) transformer project run by Siemens The project started in October 1996 and ended in September 2001 The aim of the project was to show the future prospects for superconducting railway transformers To study the principle behavior of such a transformer the authors as a first step designed constructed and tested a nominal single-phase transformer 100 kVA 50 Hz 55 kV11 kV After this was successfully tested we started the design and construction of a single-phase transformer 1 MVA 50 Hz 25 kV14 kV This unit already has the full ratings of a commercial transformer in many respects eg power range nominal voltage 2-limb core with horizontal orientation two secondary windings and an impedance of 25 at nominal current Further innovative features are transposed conductor and a closed cooling cycle with sub-cooled nitrogen The report describes the 1-MVA transformerrsquos detailed design and presents the results of electrical and thermal transformer routine tests (eg measurement of load losses and no-load losses) The conclusion highlights the future perspective of HTS transformers for railway applications
INTRODUCTION
Transformer is a static device which transfer electrical energy from one circuit to another circuit without changing its frequency
Transformer is an heart of substation
WHAT IS THE TRANSFORMER
A Ratings
The single-phase transformer has a nominal frequency of 50 Hz It has two identical LV windings taken toward the outside The HV winding has a nominal voltage of 25 kV and a nominal current of 40 A The LV windings have a nominal voltage of 1389 V and a nominal current of 360 A The nominal impedance voltage is 25
B Core-and-Coil Assembly
The core-and-coil assembly consists of a 2-limb core whereby each limb is wound The winding structures of the two limbs are identical except for the direction of winding The windings are arranged in a doubly concentric layout in the radial sequence LV inside-HV-LV outside The HV windings of the two limbs are connected in parallel
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
INTRODUCTION
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
ASSEMBLY AND COOL DOWN
TEST RESULTS
CONCLUSION
REFRENCES
CONTENTS
We describe the high-temperature superconducting (HTS) transformer project run by Siemens The project started in October 1996 and ended in September 2001 The aim of the project was to show the future prospects for superconducting railway transformers To study the principle behavior of such a transformer the authors as a first step designed constructed and tested a nominal single-phase transformer 100 kVA 50 Hz 55 kV11 kV After this was successfully tested we started the design and construction of a single-phase transformer 1 MVA 50 Hz 25 kV14 kV This unit already has the full ratings of a commercial transformer in many respects eg power range nominal voltage 2-limb core with horizontal orientation two secondary windings and an impedance of 25 at nominal current Further innovative features are transposed conductor and a closed cooling cycle with sub-cooled nitrogen The report describes the 1-MVA transformerrsquos detailed design and presents the results of electrical and thermal transformer routine tests (eg measurement of load losses and no-load losses) The conclusion highlights the future perspective of HTS transformers for railway applications
INTRODUCTION
Transformer is a static device which transfer electrical energy from one circuit to another circuit without changing its frequency
Transformer is an heart of substation
WHAT IS THE TRANSFORMER
A Ratings
The single-phase transformer has a nominal frequency of 50 Hz It has two identical LV windings taken toward the outside The HV winding has a nominal voltage of 25 kV and a nominal current of 40 A The LV windings have a nominal voltage of 1389 V and a nominal current of 360 A The nominal impedance voltage is 25
B Core-and-Coil Assembly
The core-and-coil assembly consists of a 2-limb core whereby each limb is wound The winding structures of the two limbs are identical except for the direction of winding The windings are arranged in a doubly concentric layout in the radial sequence LV inside-HV-LV outside The HV windings of the two limbs are connected in parallel
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
We describe the high-temperature superconducting (HTS) transformer project run by Siemens The project started in October 1996 and ended in September 2001 The aim of the project was to show the future prospects for superconducting railway transformers To study the principle behavior of such a transformer the authors as a first step designed constructed and tested a nominal single-phase transformer 100 kVA 50 Hz 55 kV11 kV After this was successfully tested we started the design and construction of a single-phase transformer 1 MVA 50 Hz 25 kV14 kV This unit already has the full ratings of a commercial transformer in many respects eg power range nominal voltage 2-limb core with horizontal orientation two secondary windings and an impedance of 25 at nominal current Further innovative features are transposed conductor and a closed cooling cycle with sub-cooled nitrogen The report describes the 1-MVA transformerrsquos detailed design and presents the results of electrical and thermal transformer routine tests (eg measurement of load losses and no-load losses) The conclusion highlights the future perspective of HTS transformers for railway applications
INTRODUCTION
Transformer is a static device which transfer electrical energy from one circuit to another circuit without changing its frequency
Transformer is an heart of substation
WHAT IS THE TRANSFORMER
A Ratings
The single-phase transformer has a nominal frequency of 50 Hz It has two identical LV windings taken toward the outside The HV winding has a nominal voltage of 25 kV and a nominal current of 40 A The LV windings have a nominal voltage of 1389 V and a nominal current of 360 A The nominal impedance voltage is 25
B Core-and-Coil Assembly
The core-and-coil assembly consists of a 2-limb core whereby each limb is wound The winding structures of the two limbs are identical except for the direction of winding The windings are arranged in a doubly concentric layout in the radial sequence LV inside-HV-LV outside The HV windings of the two limbs are connected in parallel
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
Transformer is a static device which transfer electrical energy from one circuit to another circuit without changing its frequency
Transformer is an heart of substation
WHAT IS THE TRANSFORMER
A Ratings
The single-phase transformer has a nominal frequency of 50 Hz It has two identical LV windings taken toward the outside The HV winding has a nominal voltage of 25 kV and a nominal current of 40 A The LV windings have a nominal voltage of 1389 V and a nominal current of 360 A The nominal impedance voltage is 25
B Core-and-Coil Assembly
The core-and-coil assembly consists of a 2-limb core whereby each limb is wound The winding structures of the two limbs are identical except for the direction of winding The windings are arranged in a doubly concentric layout in the radial sequence LV inside-HV-LV outside The HV windings of the two limbs are connected in parallel
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
A Ratings
The single-phase transformer has a nominal frequency of 50 Hz It has two identical LV windings taken toward the outside The HV winding has a nominal voltage of 25 kV and a nominal current of 40 A The LV windings have a nominal voltage of 1389 V and a nominal current of 360 A The nominal impedance voltage is 25
B Core-and-Coil Assembly
The core-and-coil assembly consists of a 2-limb core whereby each limb is wound The winding structures of the two limbs are identical except for the direction of winding The windings are arranged in a doubly concentric layout in the radial sequence LV inside-HV-LV outside The HV windings of the two limbs are connected in parallel
DESIGN OF 1-MVA TRANSFORMER SUBGROUPS
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
C Core
Because the core is placed in liquid nitrogen and therefore contributes to the cold losses a high-quality plasma-treated type of sheet with a thickness of 023 mm and specific loss of 085 Wkg (Epstein square value) at 17 T and 50 Hz was selected in contrast to 15 Wkg in conventional traction Transformers
D Conductor
Bi-2223 tape made in 1999 by Vacuum schmelze GmbH with a pure silver matrix and a silver-magnesium sheath was used as conductor The tape consists of 55 filaments and is not twisted A conductor length of 67 km representing a mass of 54 kg was used in the windings
E HV WindingHV1 and HV2 each consist of a stack of 9 identical coils
each stack having 224 turns The individual coils are connected in series by means of a tot-to-top bottom-to-bottom inter coil connection and the total number of turns is 2016
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
F LV Winding
The inner and outer LV windings are layer wound each with one layer and 56 turns per layer At the lower end the inner and outer windings are connected to each other in series The LV windings taken to the outside therefore have a total number of turns of 112 The already mentioned transposed conductor is used
G Leakage Flux Iron
The leakage flux iron is a complex periodic structure made up of air gaps and iron sheets with the size of a centimeter square
H Liquid Nitrogen Container
The LN container is made of stainless steel and its volume is optimally matched to the core-and-coil assembly During nominal operation it contains 250 l of liquid nitrogen with a mass of 200 kg The inner and outer dimensions are 420 mm 832 mm 1200 mm and 430 mm 842 mm 1245 respectively Its empty mass is 272 kg
K Cooling SystemThe cooling system consists of a 4-cylinder Stirling cryo
generator an electric motor a coupling cryostat and a control cabinet In order to save time and money the cold head was not optimized for 66 K
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
ASSEMBLY AND COOL DOWN
Core-and-coil assembly of the 1-MVA HTS transformer3-d schematic arrangement of the complete set-up
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
1-MVA HTS transformer with cooling system in test laboratory atthe Nuremberg transformer factory (1) 4-cylinder Starling cry generator (2)coupling cryostat (3) vacuum-tight conventional tank with LN container andcore-and-coil assembly inside temperature inside1048576196 C temperature outside+20 C
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
Pretest
After the operating temperature of 67 K was reached the following were performed Measurement of winding resistance insulation resistance test insulation capacitance test coil-coil insulation test at 7 kV 50 Hz for 60 s measurement of frequency response (impedance and ratio for 30 Hzndash3 MHz) measurement of response characteristic of transient voltages (full and chopped) These tests were all passed and the measured values were again good
B Measurement of Impedance Voltage and Load Loss
After this the impedance voltage and the load losses were measured for 50 Hz and 167 Hz at 67 K The HV winding was charged LV1 and LV2 were short-circuited Fig 5 shows the reactive component of the percentage impedance voltage as a function of the current in the HV winding at nominal value At nominal current the reactance voltage was measured and found to be 2430 This very closely agrees with the calculated value of 25
TEST RESULTS
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
The advantages of stationary HTS transformers compared to transformers
1 normal conductivity are well
2 higher current densities
3 The efficiency is raised to over 99 whereas the weight and volume can be reduced by approximately 45
4 It is mostly designed for superconducting application
ADVANTAGES
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
After the plan to develop a 1-MVA HTS transformer was completed last year the engineering documents are now being drawn up to build a full power on-board transformer with A planned follow-up project envisages construction assembly stationary and mobile tests and testing of the new pioneering technology of a superconducting railway transformer on a trial vehicle
CONCLUSION AND OUTLOOK
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
1 S Mehta N Aversa and M S Walker ldquoTransforming transformersrdquo IEEE Spectrum
2 wwwtransforming transformer com
3 P Kummeth et al ldquoDevelopment and test of a 100 kVA superconducting transformer operated at 77 Krdquo
REFERENCES
THANK YOU
ANY QUESTION
THANK YOU
ANY QUESTION
ANY QUESTION