Research at the Department

Electromagnetic design of electrical machines

It is an essential building block of electrical machines. No machine could be built without precise calculation and design. This is how machines are created that make your life easier in practice. There are many derived mathematical equations behind it. It is necessary to consider the machine as a sub-part of a complex drive. That is why there is a strong synergy between the two teams in our department. Without this interconnection, it is impossible to develop a properly tuned modern drive. Electromagnetic design alone would not be feasible. Therefore, synergy with designers, technologists and electrical machine manufacturers is important.

STRUCTURAL DESIGN OF ELECTRICAL MACHINES AND THEIR SIMULATION

All parts must work together to create a machine with a long service life. In particular, mechanical calculations and vibration simulations are important for the early detection of design errors. For the designer of a new electrical machine, it is important to reconcile electromagnetic behaviour with mechanical design and safe torque transmission. It is also important not to forget the thermal calculation of the machine to verify the thermal behaviour. This has a great influence on the overall reliability and lifetime of the machine. Due to this, it is usually necessary to combine weakly and strongly coupled problems by finite element methods. Our team performs complex simulations and modelling of rotating and non-rotating machines in ANSYS, MATLAB SOLIDWORKS and COMSOL.

Thermo-Ventilation modelling of electrical machines

Verification by thermal calculation is an integral part of the design methods. This is the only way to refine the machine design to its final form. The thermal model of the machine can predict the behaviour of the machine under load. Currently, we have already included the now-neglected modelling of the flow and behaviour of the refrigerant both in and around the machine in our simulations, and thus achieve a high agreement of the models with real measurements. These allow further refinement of results in advanced thermal calculations based on knowledge of the refrigerant behaviour in the machine. This important part of thermal calculation has been made possible by the development of simulation methods. Using accurate calculations and simulations, it is then possible to let previously unthinkable cooling systems and designs emerge.

Fig.: Airflow on an industrial engine

Airflow on the proposed drive for a racing kart

Measurement and testing of electrical machines

The team's favourite activity is always testing the finished new engine. Before the engines can be tested, however, they must be accurately balanced and set up. For this reason, we have state-of-the-art alignment lasers at our disposal. We have a small test lab with various sources up to 40 kW load power and a larger indoor RICE lab where we can test machines up to 2 MW and at various voltage levels. As a result, we are never limited. We also have a variety of water and oil cooling systems.

We are the only workplace with the possibility to measure and load machines up to 12,000 revolutions and 160kW of power thanks to the BRUSA - YASA motor set, which is interesting because of the combination of high-speed machines of double construction, namely radial and axial. Thanks to the possibility of adjusting different axial heights and the continuous development of new stands, we are able to combine and load machines in a uniquely wide range of power and speeds