Potential evaluation for material reduction by different cooling topologies in electric traction machines



Christian Monissen

Research Associate


+49 241 80-24220



Apart from the battery, the electric machine has the highest potential for reducing critical resources in the electric powertrain. By increasing the power density and improving the cooling, machine concepts with lower material requirements can be realized. The higher power density leads to higher temperatures of the machine and thus requires better cooling. The cooling concepts currently used do not yet allow component-separate control of the electrical machine. As a result, temperature dependencies of the individual loss components can only be insufficiently exploited to minimize the total losses during operation. Simulative preliminary work has already shown the potential with regard to loss optimization for separately temperature-controlled machine components.

In the MatReK research project, funded by the " - Research" program of North Rhine-Westphalia, a drive unit of a state-of-the-art electric vehicle with multiple, component cooling systems is being procured for validation and equipped with a rotor temperature telemetry system. The electric machine will be tested on the test bench with new cooling approaches and resulting control strategies in order to validate its performance and to reveal further potential for material reduction. The overload capacity of the different cooling systems and the reserves until overheating are evaluated in representative driving cycles. Based on these reserves and the overload capacity, a newly dimensioned and adapted machine can be designed to minimize losses and reduce material requirements for critical resources.



Ministerium für Wirtschaft, Innovation, Digitalisierung und Energie des Landes Nordrhein-Westfalen