Monte Carlo Design Space Exploration of Superconducting Wind Generator Using MgB2 and YBCO Conductors

Abstract

Considering the global outcry over climate change and the need for increased penetration of clean forms of energy in ever-increasing aspects of the modern economic sphere, wind power installations, particularly offshore, are expected to rise in the next decades. However, the main obstacle to this trend will be represented by the high installation costs. In order to reduce these costs, the wind turbines generators require to be manufactured to yield higher torque density with lower material input in terms of weight. One way to pursue this requirement is to employ high-temperature superconductor (HTS) technology for the rotor windings and/or the stator windings, making it possible to design cheaper generators for 10-MW applications. This work considers the impact of HTS conductors in wind turbine generators to complement material research work at the University of Houston HTS material research work. Four topologies of generators were investigated: two partially superconducting generators employing YBCO and MgB2 as conductor for the rotor windings and two fully superconducting generators employing MgB2. The electromagnetic physics governing the machine was simulated by finite-element analysis software, i.e., FlexPDE; then, a numerical analysis of thousands of models was realized by Python. An exploration of the results was carried out making use of an optimum criterion considering a simple aggregation of the generator mass active, the copper, ac stator windings losses, and the amount of superconductor needed. Trends of these optimization criteria with reference to design parameters are shown in detailed plots. According to the specific aims of the designer, the investigation provided interesting clues regarding, among others, the number of pair of poles and the amount of superconductor employed characterizing the best models.