Optimization of the Superconducting Linear Magnetic Bearing of a Maglev Vehicle

Considering the need for cost/performance prediction and optimization of superconducting maglev vehicles, we develop and validate here a 3D finite element model to simulate superconducting linear magnetic bearings. Then we reduce the 3D model to a 2D model in order to decrease the computing time. This allows us to perform in a reasonable time a stochastic optimization considering the superconductor properties and the vehicle operation. We look for the permanent magnet guideway geometry that minimizes the cost and maximizes the lateral force during a displacement sequence, with a constraint on the minimum levitation force. The displacement sequence reproduces a regular maglev vehicle operation with both vertical and lateral movements. For the sake of comparison, our reference is the SupraTrans prototype bearing. The results of the optimization suggest that the bearing cost could be substantially reduced, while keeping the same performances as the initial design. Alternatively, the performances could be significantly improved for the same original cost

A new benchmark problem for electromagnetic modelling of superconductors: the high- T c superconducting dynamo

Abstract: The high-T c superconducting (HTS) dynamo is a promising device that can inject large DC supercurrents into a closed superconducting circuit. This is particularly attractive to energise HTS coils in NMR/MRI magnets and superconducting rotating machines without the need for connection to a power supply via current leads. It is only very recently that quantitatively accurate, predictive models have been developed which are capable of analysing HTS dynamos and explain their underlying physical mechanism. In this work, we propose to use the HTS dynamo as a new benchmark problem for the HTS modelling community. The benchmark geometry consists of a permanent magnet rotating past a stationary HTS coated-conductor wire in the open-circuit configuration, assuming for simplicity the 2D (infinitely long) case. Despite this geometric simplicity the solution is complex, comprising time-varying spatially-inhomogeneous currents and fields throughout the superconducting volume. In this work, this benchmark problem has been implemented using several different methods, including H-formulation-based methods, coupled H-A and T-A formulations, the Minimum Electromagnetic Entropy Production method, and integral equation and volume integral equation-based equivalent circuit methods. Each of these approaches show excellent qualitative and quantitative agreement for the open-circuit equivalent instantaneous voltage and the cumulative time-averaged equivalent voltage, as well as the current density and electric field distributions within the HTS wire at key positions during the magnet transit. Finally, a critical analysis and comparison of each of the modelling frameworks is presented, based on the following key metrics: number of mesh elements in the HTS wire, total number of mesh elements in the model, number of degrees of freedom, tolerance settings and the approximate time taken per cycle for each model. This benchmark and the results contained herein provide researchers with a suitable framework to validate, compare and optimise their own methods for modelling the HTS dynamo

A new benchmark problem for electromagnetic modelling of superconductors: the high-Tc_{c} superconducting dynamo

The high-T$_{c}$ superconducting (HTS) dynamo is a promising device that can inject large DC supercurrents into a closed superconducting circuit. This is particularly attractive to energise HTS coils in NMR/MRI magnets and superconducting rotating machines without the need for connection to a power supply via current leads. It is only very recently that quantitatively accurate, predictive models have been developed which are capable of analysing HTS dynamos and explain their underlying physical mechanism. In this work, we propose to use the HTS dynamo as a new benchmark problem for the HTS modelling community. The benchmark geometry consists of a permanent magnet rotating past a stationary HTS coated-conductor wire in the open-circuit configuration, assuming for simplicity the 2D (infinitely long) case. Despite this geometric simplicity the solution is complex, comprising time-varying spatially-inhomogeneous currents and fields throughout the superconducting volume. In this work, this benchmark problem has been implemented using several different methods, including H-formulation-based methods, coupled H-A and T-A formulations, the Minimum Electromagnetic Entropy Production method, and integral equation and volume integral equation-based equivalent circuit methods. Each of these approaches show excellent qualitative and quantitative agreement for the open-circuit equivalent instantaneous voltage and the cumulative time-averaged equivalent voltage, as well as the current density and electric field distributions within the HTS wire at key positions during the magnet transit. Finally, a critical analysis and comparison of each of the modelling frameworks is presented, based on the following key metrics: number of mesh elements in the HTS wire, total number of mesh elements in the model, number of degrees of freedom, tolerance settings and the approximate time taken per cycle for each model. This benchmark and the results contained herein provide researchers with a suitable framework to validate, compare and optimise their own methods for modelling the HTS dynamo

Contributions à l'évaluation technico-économique des innovations technologiques en génie électrique

The energy transition to a low-carbon society is both a major challenge for innovation and a great opportunity for the economy. Technology choices must be well thought out because they have long-term impacts. This is due to the evolution of the technical and environmental performance of each element of a system over its lifetime and to the huge levels of investment involved. Therefore, in addition to demonstrating the technical feasibility of an innovation, it is also necessary to evaluate its economic competitiveness throughout its life cycle.In this context, first we discuss a framework for the techno-economic assessment of a technological innovation. Then we focus on 4 early-stage technologies being developed at GeePs, CentraleSupélec, University Paris-Saclay: fully superconducting generator for wind energy conversion systems, superconducting cables for HVAC underground cable transmission systems, cryo-modular multilevel converter for HVDC converter stations, SAUREA’s motor-pump for photovoltaic water pumping systems.For each innovation, we highlight some of the theoretical and experimental contributions of our team in recent years, and we open the discussion with an abbreviated techno-economic evaluation. Finally, we propose some perspectives both in terms of methods and applications.La transition énergétique vers une société bas carbone est à la fois un défi majeur pour l'innovation et une grande opportunité pour l'économie. Les choix technologiques doivent être mûrement réfléchis car ils ont des impacts à long terme. Cela est dû à l'évolution des performances techniques et environnementales de chaque élément du système au cours de sa durée de vie et aux énormes niveaux d'investissement impliqués. C'est pourquoi, en plus de démontrer la faisabilité technique d'une innovation, il est également nécessaire d'évaluer sa compétitivité économique en considérant son cycle de vie.Dans ce contexte, nous discutons d'abord d'un cadre pour l'évaluation technico-économique d'une innovation technologique. Ensuite, nous nous concentrons sur 4 technologies en phase de développement au GeePs, CentraleSupélec, Université Paris-Saclay : générateur entièrement supraconducteur pour les systèmes de conversion de l'énergie éolienne, câbles supraconducteurs pour les systèmes de transmission par câble souterrains HVAC, cryo-convertisseur modulaire multiniveaux pour les stations de conversion HVDC, et motopompe SAUREA pour les systèmes de pompage d'eau photovoltaïque.Pour chaque innovation, nous soulignons les contributions théoriques et expérimentales de notre équipe au cours des dernières années, et nous ouvrons la discussion en proposant une courte évaluation technico-économique. Enfin, nous présentons quelques perspectives tant au niveau méthodologique qu’applicatif

Contributions à l'évaluation technico-économique des innovations technologiques en génie électrique

The energy transition to a low-carbon society is both a major challenge for innovation and a great opportunity for the economy. Technology choices must be well thought out because they have long-term impacts. This is due to the evolution of the technical and environmental performance of each element of a system over its lifetime and to the huge levels of investment involved. Therefore, in addition to demonstrating the technical feasibility of an innovation, it is also necessary to evaluate its economic competitiveness throughout its life cycle.In this context, first we discuss a framework for the techno-economic assessment of a technological innovation. Then we focus on 4 early-stage technologies being developed at GeePs, CentraleSupélec, University Paris-Saclay: fully superconducting generator for wind energy conversion systems, superconducting cables for HVAC underground cable transmission systems, cryo-modular multilevel converter for HVDC converter stations, SAUREA’s motor-pump for photovoltaic water pumping systems.For each innovation, we highlight some of the theoretical and experimental contributions of our team in recent years, and we open the discussion with an abbreviated techno-economic evaluation. Finally, we propose some perspectives both in terms of methods and applications.La transition énergétique vers une société bas carbone est à la fois un défi majeur pour l'innovation et une grande opportunité pour l'économie. Les choix technologiques doivent être mûrement réfléchis car ils ont des impacts à long terme. Cela est dû à l'évolution des performances techniques et environnementales de chaque élément du système au cours de sa durée de vie et aux énormes niveaux d'investissement impliqués. C'est pourquoi, en plus de démontrer la faisabilité technique d'une innovation, il est également nécessaire d'évaluer sa compétitivité économique en considérant son cycle de vie.Dans ce contexte, nous discutons d'abord d'un cadre pour l'évaluation technico-économique d'une innovation technologique. Ensuite, nous nous concentrons sur 4 technologies en phase de développement au GeePs, CentraleSupélec, Université Paris-Saclay : générateur entièrement supraconducteur pour les systèmes de conversion de l'énergie éolienne, câbles supraconducteurs pour les systèmes de transmission par câble souterrains HVAC, cryo-convertisseur modulaire multiniveaux pour les stations de conversion HVDC, et motopompe SAUREA pour les systèmes de pompage d'eau photovoltaïque.Pour chaque innovation, nous soulignons les contributions théoriques et expérimentales de notre équipe au cours des dernières années, et nous ouvrons la discussion en proposant une courte évaluation technico-économique. Enfin, nous présentons quelques perspectives tant au niveau méthodologique qu’applicatif

Introduction to Techno-Economic Assessments of HTS Systems

École thématiqueThe scientific and industrial interest in superconducting power cables has experienced significant growth in recent years due to their technological advantages over traditional cables in specific scenarios. Indeed, it is only through techno-economic analyses (TEA) that potential cost-effective solutions can be identified. This lecture provides an introduction to TEA approaches, specifically applied to superconducting cable systems. A case study involving a medium-voltage AC cable in a co-axial configuration using High-Temperature Superconducting (HTS) tapes is examined. Simplified equations are presented to derive the technical parameters of the cable and calculate the required economic indexes. A hands-on activity is proposed, where students will implement the equations and will interpret the outcomes, understanding convenient alternatives compared to conventional technology benchmarks. Additionally, advanced TEA optimization models will be introduced to refine solutions by minimizing approximations

Hands-on Techno Economic Assessment: HTS cable system

École thématiqueThe scientific and industrial interest in superconducting power cables has experienced significant growth in recent years due to their technological advantages over traditional cables in specific scenarios. Indeed, it is only through techno-economic analyses (TEA) that potential cost-effective solutions can be identified. This lecture provides an introduction to TEA approaches, specifically applied to superconducting cable systems. A case study involving a medium-voltage AC cable in a co-axial configuration using High-Temperature Superconducting (HTS) tapes is examined. Simplified equations are presented to derive the technical parameters of the cable and calculate the required economic indexes. A hands-on activity is proposed, where students will implement the equations and will interpret the outcomes, understanding convenient alternatives compared to conventional technology benchmarks. Additionally, advanced TEA optimization models will be introduced to refine solutions by minimizing approximations

Hands-on Techno Economic Assessment: HTS Busbar

École thématiqu