Research projects:
Grand Challenge 1.3

Light-weighting and multi-functional non-active components
Led by University of Strathclyde

One of the main streams of work for GC1.3 in the past two years has been the development of a methodology to fully integrate manufacturing constraints and opportunities with the machine design considerations. The novelty in this work includes material data specific to individual manufacturing process in the design of components. Not only does this reduce the risk of over-engineering components, it also allows for an assessment of when and where expensive materials and processing routes can be put to best use.

 In 2022, the team working on GC1.3 published the paper “A Manufacturing Driven Design Methodology to Lightweighting of the Structural Elements of a Permanent Magnet Electrical Machine Rotor,” in IEEE Access [1]. This paper was the culmination of over a year’s work, optimising how the manufacturing requirements can be optimally integrated into the design stage of electrical machines components. Typically, electrical machines are designed with little or no input from a manufacturing production viewpoint, and this can often lead to cost increases and time delays as designs are iterated to accommodate for manufacturing limitations. This paper proposed a methodology to fully integrate the mechanical design and manufacturing process routes into electrical machine design, and illustrated the benefits of such a process within the context of lightweighting a permanent magnet rotor for an aerospace electrical machine. 

Within the methodology proposed in this paper, several alternative configurations of rotor design were considered with appropriate manufacturing routes identified at the initial concept design. Different material and manufacturing constraints were identified in this paper, as well as the impact that the manufacturing process can have on the final component. These impacts were then embedded into the initial design procedures. The final section of the paper demonstrated an application of this methodology, and discussed the features which offer opportunities for achieving economically lighter weight design through the integration of manufacturing into the design procedure 

For the next phase of this research, there will be two main work streams: • Work stream 1: Continuation of current lightweighting design development, with methodology validation and prototype testing • Work stream 2: Manufacturing-driven design of down-scaled wind turbine direct-drive generator Work stream 1 will build on previous research and will produce high-fidelity finite element modelling and analysis of family tree design candidates presented in [1]. “A Manufacturing Driven Design Methodology to Lightweighting of the Structural Elements of a Permanent Magnet Electrical Machine Rotor” [1] set out a methodology for determining the optimal material and manufacturing route for specific electrical machines components. The next stage will involve stress and compliance analysis of the design candidates where the joint manufacturing and mechanical constraints are imposed, and the use of different metallic materials with the mechanical properties associated with the manufacturing process taken into account. Based on the results of the finite element modelling, a design will be chosen for prototype manufacture. Mechanical tests will then be conducted on the manufactured candidate design under operational loads. Shaft and hub mechanical strength tests will be conducted, including stress, deflection, tolerance, vibration measurements, and verification against the finite element analysis results. 

Work stream 2 will follow on from the white paper “Design and Manufacturing Challenges and Opportunities for Offshore Wind Turbine Electrical Generators”. Downscaling, modelling, redesign and testing will be conducted in order to establish the comparison with the baseline design. An adaptation of the design and manufacturing methodology developed in [1] will be applied to the rotor of a direct-drive generator to create novel candidate design models. Finite element modelling will be utilised for a multi-material rotor design, which aims to utilise carbon fibre composite in the deflection hotspots in combination with a metallic structure for further lightweighting achievement in addition to the above. Focus will be given to the achievable tolerances, mechanical strength of the novel rotor design, and electromagnetic losses in the generator