# Topology Comparison of Superconducting Generators for 10-MW Direct-Drive Wind Turbines: Cost of Energy Based

Dong Liu, Henk Polinder, Asger Bech Abrahamsen, Jan Abraham Ferreira

Research output: Contribution to journalJournal articleResearchpeer-review

### Abstract

This paper aims at finding feasible electromagnetic designs of superconducting synchronous generators (SCSGs) for a 10-MW direct-drive wind turbine. Since a lower levelized cost of energy (LCoE) increases the feasibility of SCSGs in this application, 12 generator topologies are compared regarding their LCoE in a simplified form of levelized equipment cost of energy (LCoE$_{\text{eq}}$). MgB$_2$ wires are employed in the field winding. Based on the current unit cost and critical current density capability of the MgB $_2$ wire at 20 K, the topologies with more iron have a much lower LCoE$_{\text{eq}}$ than the topologies with more nonmagnetic cores. The fully iron-cored topology with salient poles has the lowest LCoE $_{\text{eq}}$. Then a scenario study shows that the difference of LCoE$_{\text{eq}}$ between the topologies will become much smaller when the unit cost of the MgB$_2$ wire drops to a quarter and the current density capability of the MgB $_2$ wire increases to four times. Then the topologies with more nonmagnetic cores will become comparable to those with more iron. Aiming at a lower LCoE $_{\text{eq}}$ to increase the feasibility of SCSGs for large wind turbines, those topologies having the most iron in the core are the most promising for both now and the long term. If low weight is required, the topologies with more nonmagnetic cores should be considered.
Original language English I E E E Transactions on Applied Superconductivity 27 4 7 1051-8223 https://doi.org/10.1109/TASC.2017.2668059 Published - 2017

### Keywords

• Wind turbines
• Topology
• Windings
• Generators
• Iron
• Stator cores
• Rotors
• wind turbine
• Cost of energy
• direct drive
• MgB<named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX">$_{2}$</tex-math> </inline-formula> </named-content>
• superconducting generator
• topology

### Cite this

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title = "Topology Comparison of Superconducting Generators for 10-MW Direct-Drive Wind Turbines: Cost of Energy Based",
abstract = "This paper aims at finding feasible electromagnetic designs of superconducting synchronous generators (SCSGs) for a 10-MW direct-drive wind turbine. Since a lower levelized cost of energy (LCoE) increases the feasibility of SCSGs in this application, 12 generator topologies are compared regarding their LCoE in a simplified form of levelized equipment cost of energy (LCoE$_{\text{eq}}$). MgB$_2$ wires are employed in the field winding. Based on the current unit cost and critical current density capability of the MgB $_2$ wire at 20 K, the topologies with more iron have a much lower LCoE$_{\text{eq}}$ than the topologies with more nonmagnetic cores. The fully iron-cored topology with salient poles has the lowest LCoE $_{\text{eq}}$. Then a scenario study shows that the difference of LCoE$_{\text{eq}}$ between the topologies will become much smaller when the unit cost of the MgB$_2$ wire drops to a quarter and the current density capability of the MgB $_2$ wire increases to four times. Then the topologies with more nonmagnetic cores will become comparable to those with more iron. Aiming at a lower LCoE $_{\text{eq}}$ to increase the feasibility of SCSGs for large wind turbines, those topologies having the most iron in the core are the most promising for both now and the long term. If low weight is required, the topologies with more nonmagnetic cores should be considered.",
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author = "Dong Liu and Henk Polinder and Abrahamsen, {Asger Bech} and Ferreira, {Jan Abraham}",
year = "2017",
doi = "10.1109/TASC.2017.2668059",
language = "English",
volume = "27",
journal = "I E E E Transactions on Applied Superconductivity",
issn = "1051-8223",
publisher = "Institute of Electrical and Electronics Engineers",
number = "4",

}

Topology Comparison of Superconducting Generators for 10-MW Direct-Drive Wind Turbines: Cost of Energy Based. / Liu, Dong; Polinder, Henk; Abrahamsen, Asger Bech; Ferreira, Jan Abraham.

In: I E E E Transactions on Applied Superconductivity, Vol. 27, No. 4, 2017.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Topology Comparison of Superconducting Generators for 10-MW Direct-Drive Wind Turbines: Cost of Energy Based

AU - Liu, Dong

AU - Polinder, Henk

AU - Abrahamsen, Asger Bech

AU - Ferreira, Jan Abraham

PY - 2017

Y1 - 2017

N2 - This paper aims at finding feasible electromagnetic designs of superconducting synchronous generators (SCSGs) for a 10-MW direct-drive wind turbine. Since a lower levelized cost of energy (LCoE) increases the feasibility of SCSGs in this application, 12 generator topologies are compared regarding their LCoE in a simplified form of levelized equipment cost of energy (LCoE$_{\text{eq}}$). MgB$_2$ wires are employed in the field winding. Based on the current unit cost and critical current density capability of the MgB $_2$ wire at 20 K, the topologies with more iron have a much lower LCoE$_{\text{eq}}$ than the topologies with more nonmagnetic cores. The fully iron-cored topology with salient poles has the lowest LCoE $_{\text{eq}}$. Then a scenario study shows that the difference of LCoE$_{\text{eq}}$ between the topologies will become much smaller when the unit cost of the MgB$_2$ wire drops to a quarter and the current density capability of the MgB $_2$ wire increases to four times. Then the topologies with more nonmagnetic cores will become comparable to those with more iron. Aiming at a lower LCoE $_{\text{eq}}$ to increase the feasibility of SCSGs for large wind turbines, those topologies having the most iron in the core are the most promising for both now and the long term. If low weight is required, the topologies with more nonmagnetic cores should be considered.

AB - This paper aims at finding feasible electromagnetic designs of superconducting synchronous generators (SCSGs) for a 10-MW direct-drive wind turbine. Since a lower levelized cost of energy (LCoE) increases the feasibility of SCSGs in this application, 12 generator topologies are compared regarding their LCoE in a simplified form of levelized equipment cost of energy (LCoE$_{\text{eq}}$). MgB$_2$ wires are employed in the field winding. Based on the current unit cost and critical current density capability of the MgB $_2$ wire at 20 K, the topologies with more iron have a much lower LCoE$_{\text{eq}}$ than the topologies with more nonmagnetic cores. The fully iron-cored topology with salient poles has the lowest LCoE $_{\text{eq}}$. Then a scenario study shows that the difference of LCoE$_{\text{eq}}$ between the topologies will become much smaller when the unit cost of the MgB$_2$ wire drops to a quarter and the current density capability of the MgB $_2$ wire increases to four times. Then the topologies with more nonmagnetic cores will become comparable to those with more iron. Aiming at a lower LCoE $_{\text{eq}}$ to increase the feasibility of SCSGs for large wind turbines, those topologies having the most iron in the core are the most promising for both now and the long term. If low weight is required, the topologies with more nonmagnetic cores should be considered.

KW - Wind turbines

KW - Topology

KW - Windings

KW - Generators

KW - Iron

KW - Stator cores

KW - Rotors

KW - wind turbine

KW - Cost of energy

KW - direct drive

KW - superconducting generator

KW - topology

U2 - 10.1109/TASC.2017.2668059

DO - 10.1109/TASC.2017.2668059

M3 - Journal article

VL - 27

JO - I E E E Transactions on Applied Superconductivity

JF - I E E E Transactions on Applied Superconductivity

SN - 1051-8223

IS - 4

ER -