Additive manufacturing (AM) has been identified as an enabling manufacturing technology to produce power-dense electric motors in a repeatable and short lead time. Whilst additive manufacturing isn’t new, its application for end-use parts and tooling has become more prevalent only in recent years, and is demonstrating its potential to change the way that products are designed and manufactured.
In academia, there are a growing number of research papers that highlight the benefits associated with an additive manufactured motor, however there are limited examples of AM in commercially developed products. The MTC’s technology experts initiated a project that considered the wider implications of additive manufacturing for electric motors. The aim was to provide recommendations, based on existing limitations, for creating the next generation of electric machines.
With support from the National Centre of Additive Manufacturing (NCAM) and the MTC’s Electrification Steering Committee, the project team were able to identify the key challenges being faced by conventionally manufactured motors.
Technology Readiness Level (TRL) and Manufacturing Readiness Level (MRL) assessments were conducted of additive manufacturing for key motor components. These assessments were combined with learnings from past projects and an analysis of present manufacturing techniques for each component. In doing so, the MTC was able to identify the current constraints and how, by, applying AM, these limitations may be resolved.
To demonstrate the potential benefits of leveraging the capabilities of AM, the cooling method of a commercial motor was reassessed, as a result of several iterations of a liquid-cooled motor casing.
The benefits that AM can provide for each component of electric motors were identified, and a research and development roadmap was created to outline a route for progressing the implementation of AM in electric motors. Consequently, the MTC was able to propose new projects that can address the challenges and constraints of using additive manufacturing in electric motors.
The redesign of the casing allowed the motor to produce more power by the implementation of liquid cooling channels to prevent overheating. In addition, the design freedoms of additive manufacturing enabled for a weight saving of 10% and size reduction of 30% due to component integration. These design activities were supported by the software capabilities provided by Siemens Digital Industries, such as Siemens NX for CAD modelling, digital verification and technical product specification.
The process of manufacturing electric motors has a number of challenges to overcome; complex or manual assembly, materials that are difficult to process and can be rare and/or expensive, thermal management and lightweighting.
By leveraging the AM capabilities through the product redesign as demonstrated in the casing, key benefits were identified throughout the product and supply chain:
The additive manufacturing motor roadmap provides a clear picture of the necessary developments required and potential challenges and constraints to introduce additive manufactured motors to industry.
