Master’s Thesis: Development and Experimental Validation of Lumped-Parameter Thermal Network Models for Electric Motors.

Location: Sundbyberg, Sweden

Xylem is a Fortune 500 global water solutions company dedicated to advancing sustainable impact and empowering the people who make water work every day. As a leading water technology company with 23,000 employees operating in over 150 countries, Xylem is at the forefront of addressing the world's most critical water challenges. We invite passionate individuals to join our team, dedicated to exceeding customer expectations through innovative and sustainable solutions.

Master’s Thesis: Development and Experimental Validation of Lumped-Parameter Thermal Network Models for Electric Motors.

Xylem has over 24000 people working towards a common goal: to create innovative solutions for the world's waterneeds. By developing new technologies, we improve the way water is used, stored and reused now and in the future. We transport, purify, analyze and return water to nature and help

people use water efficiently – at home, at work, in industry and in agriculture.

With more than 100 years of experience in water technology, Xylem offers a portfolio of leading product brands and expertise across a wide range of applications. This has enabled long-term customer relationships in more than 150 countries. One of Xylem’s product categories is Flygt, which

has manufactured electric motors in Sweden for over 60 years. Today, production includes direct-on-line started induction motors, line-start permanent magnet (LSPM) machines, and inverter-fed permanent magnet motors.

Student thesis proposal

With new climate and environmental challenges comes an increased need for high-capacity pumps that can operate efficiently and reliably under harsh conditions. In practice, a key limiting factor for how hard an electric pump can be run is temperature, since excessive heat reduces motor lifetime, constrains the allowable operating range, and can trigger derating. As a result,

thermal management of electric motors has become a central engineering focus across multiple industries, from electric vehicles to pumping applications.

CFD/FEM tools are used in Xylem’s R&D department for thermal analysis of electric motors. In parallel, simplified thermal models can be used earlier in the design process. For example, lumped-parameter thermal networks (LPTNs) offer a fast and transparent way to evaluate multiple design iterations (e.g., geometry, materials, cooling concepts, and operating points) before committing resources to detailed simulations.

The aim of this thesis is to develop lumped-parameter thermal networks for induction motors and validate the models against experimental measurements. The work will focus on building thermal networks that capture the main heat sources and heat transfer paths in the motor, parameterizing the model using available motor data and targeted measurements, and

assessing accuracy under relevant operating conditions. Model performance will be evaluated through steady-state comparisons of predicted temperatures at key locations (e.g., windings, stator, housing, and end-windings where applicable) with measurements from heat tests.

The work will be carried out on site at Xylem’s office in Sundbyberg which has access to a dedicated motor test facility for controlled thermal testing. This enables efficient experimental verification of the developed models and short feedback cycles between modeling and testing.

The work will primarily use Python for model development and data analysis. Familiarity with Creo is preferred for exploring motor geometry and supporting model setup.

The time period is flexible, but preferably in spring 2027. A suitable background is mechanical engineering, engineering mechanics, mechatronics, engineering physics, applied physics, or applied mechanics.

Please contact Keith Lothian, Manager of Mechanics and Materials within R&D, for questions about the thesis.

[email protected]

+46 8 475694

Join the global Xylem team to be a part of innovative technology solutions transforming water usage, conservation, and re-use. Our products impact public utilities, industrial sectors, residential areas, and commercial buildings, with a commitment to providing smart metering, network technologies, and advanced analytics for water, electric, and gas utilities. Partner with us in creating a world where water challenges are met with ingenuity and dedication; where we recognize the power of inclusion and belonging in driving innovation and allowing us to compete more effectively around the world.