Our work and work packages


Important date: Hipo conference in DTU 7-9 May 2025. All beneficiars, partners and doctoral students should attend face-to-face in Denmark.

Measurements of steel samples from KIT are performed in LUT with a permeameter. The normalization curve and hysteresis curve of 8 novel (manufactured from 2 different materials) steel samples is recorded and analysed.

Dissertation event 14.6.2024 in LUND University: professor Liu in the committee and coordinator Lindh acted as opponent.  The doctoral student is Samuel Estenlund and title of his work is "Direct cooled hollow windings - for an EESM field winding".

Researcher Fedor Levchenko is on secondment visit in LUT University investatigating mechanial shear stresses of rotor materials manufactured in KIT laboratories.

Latest results in an IEEE Access journal

Design and Optimization of a Bridgeless Rotor for Synchronous Reluctance Machine, Arash Allahyari & al.

https://ieeexplore-ieee-org.ezproxy.cc.lut.fi/document/10526259

ABSTRACT A bridgeless rotor of a synchronous reluctance machine is proposed to enhance the performance of high-power and -speed synchronous reluctance machines (SynRMs). Unlike traditional transversally laminated designs that rely on radial and tangential ribs or bridges to provide mechanical integrity for the rotor, the suggested rotor incorporates separate flux guides attached to non-magnetic back plates to form SynRM rotor modules that are stacked on the shaft of the machine. This innovative structure eliminates the need for radial and tangential bridges which form a performance-deteriorating bottleneck in the design of high-power SynRMs. The paper presents a detailed analysis of the electromagnetic and mechanical aspects of the proposed bridgeless rotor synchronous reluctance machine (BLRSynRM). Furthermore, a comprehensive optimization method is implemented to demonstrate the capabilities of the proposed BLRSynRM along with comparison with conventional transversally laminated SynRM. The results show a significant increase in torque and power factor compared with conventional structure rotor. However, the proposed bridgeless structure introduces new electromagnetic and mechanical challenges to machine design and they are explained and overcome in this research.

Work Packages in the project:

In high-speed applications the operation temperature is in focus as high specific power is required. Thereby, heat transfer phenomena in all components is optimized to the best level. WP 3 focuses on energy and material efficient high-speed drive systems. These are required in several industrial and mobile applications. Heat transfer and optimised performance of the electric devises are investigated in WP 4 as high specific power is required especialy in mobile applications like aviation, trains and off-road machines. An important aspect in industrial and economics is deeply studied in WP5 sustainability of high-speed drives.

In all these WPs we take into account that industrial and mobile applications may differ significantly from each other as shown in Figure below. Industrial applications need before all reliability, high efficiency and maintainability while mobile applications require high specific power.

WP 3 ENERGY- AND MATERIAL-EFFICIENT HSM-drive systems

WP3 focuses on research of Energy- and material-efficient HSM-drive systems. An integrated system requires to combine different disciplines of control and operation, materials, and sustainable manufacturing process, cooling and thermal management, mission profile analysis and electric machinery and therefore multidisciplinary models are established.

WP 4  HIGH SPECIFIC POWER IN MOBILE APPLICATIONS

The methodology can be verified by prototype testing for the most energy- and material-efficient HSM-drive system in maximally one megawatt power range. The novelty in this research is to combine electric motor design and power electronics with control technology design aspects, giving skills of both to all DCs. In addition to the scientific aim, the DN target is to enhance the quality of the doctoral training practices through the training programme.

One objective is to use the developed high-fidelity modelling methods to find design solutions for a high specific power (power-to-weight-ratio) drive system required in mobile applications. (WP4) This research branch is needed in mobile applications in order to diminish energy consumption and increase reliability and decrease the vehicle weight. To reach high-specific power level better cooling methods are needed, which are heat-pipes, direct liquid cooling, phase-change, and other novel method.

WP 5 SUSTAINABILITY

WP5 Sustainability aims for Development of process chains for functional integration and performance improvement of EV motor components. With Precision Engineering design principles and Precision Manufacturing solutions it will be achieved small tolerances, small air gaps, higher torque, and lower losses. The integrated design removes many barriers (WP5) from the system, e.g. the cable losses, problems of the reflected voltage pulses, the feedback signal routing (temperatures, shaft position, currents). The integrated design method seeks for new possibilities to create more reliable and flexible systems, especially for mobile applications, the volume and mass are limiting factors.