Moving beyond Rare Earth Magnets

Rare earth magnets have historically been a critical component in the manufacture of large-scale wind turbine generators; however, they are rarely found in concentrated form. They are typically dispersed with other elements which makes them difficult and expensive to mine. Additionally, the extraction and processing of rare earth magnets from the mined ore is a toxic and potentially environmentally damaging process, which adds to cost and risk.

New ground-breaking wind turbine technology

GreenSpur has broken scientific barriers and has overcome previously unresolved issues of efficiency, weight and output through their creation of a ferrite based Axial Flux Direct Drive Permanent Magnet Generator. This game-changing technology will disrupt the wind turbine generator market by delivering large-scale electrical output while vastly reducing the cost of manufacture. This GreenSpur design substantially reduces manufacturing costs and significantly increases sustainability by using ferrite instead of rare earth magnets. Ferrite is in abundant supply which will resolve future supply chain availability.

Benefits of GreenSpur’s Ferrite Permanent Magnet Generator
  • Significant reduction in cost
  • Optimised electricity yield
  • Ease of supply – a less constrained supply chain
  • Improved sustainability through the use of an abundant material that has no adverse environmental impact.
Xi’s Role : R&D Partner

GreenSpur had to breakthrough previously unresolved technological difficulties to develop a design that delivers the output, dimensions, mass, and efficiencies needed by the wind turbine industry. Xi provided GreenSpur with robust, scalable multi-physics models that allowed them to make critical design decisions quicker while considering acoustic, vibration, thermal, magnetic and electrical factors. These models, along with Xi’s extensive experience in the renewables sector, assisted GreenSpur to create designs with a competitive edge, efficient operations and maximised output. GreenSpur’s product is bringing cleaner and more sustainable green energy of the future to today through clever design and innovative thinking. This is truly a leading-edge and boundary-breaking technology that Xi has been proud to be a part of.

How Xi Helped

Many design choices affect the performance of generators. These include the size, number of magnets, the materials used for the coils and geometric features such as the diameter of the rotor/stator and air spacing. The performance of the generator must be assessed on a range of criteria including the electrical yield, cost of materials, weight per megawatt, ease of manufacture and dynamic performance. The design is further complicated by the interconnected nature of electromagnetism, rotational- and structural-dynamics. The optimisation of the novel and complex generator design using trial and error physical prototyping and testing is incredibly expensive and time-consuming. Instead, Xi developed a series of numerical simulations using COMSOL Multiphysics to rapidly trial different design choices allowing an assessment of output power and cost-benefit analysis. The models fully-couple electromagnetics, rotating machinery and electric circuit to allow a design modification to be assessed within hours – compared to week or months if a similar change was made with a physical prototype. The models can also be coupled to thermal dynamics, structural mechanics or acoustic finite element modules to allow the assessment of heat, vibration and sound output. These models provided a powerful tool for assessing the output power, CAPEX and OPEX costs of the Green Spur generator.

Skill Set Used
  • Virtual prototyping of generator using COMSOL Multiphysics
  • Electromagnetic – structural dynamics coupling
  • Optimisation of generator layout
  • Comparison of power output for different materials
  • Mass to power calculates and cost-benefit analysis
Client Benefits
  • Reduced time to market
  • Optimised design
  • Reduced cost
  • Technical due diligence
  • Quick response time for client’s clients
  • Increased power production
  • Reduced carbon footprint
Working With Xi

To give our clients technical understanding and insight we have a three-phased approach which can be used to underpin some or all of the aspects of your project.

“We engaged Xi Engineering for their evident expertise in modelling, their clear understanding of the industry, the technology, the markets and their professional positive and enthusiastic mindset. We have been delighted with their work on our behalf. We are looking forward to developing our technology alongside Xi Engineering.”

Andrew Hine
Commercial Director
GreenSpur Wind Limited