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As a result of the Kyoto Protocol [1], the European Union's legislation demands higher saving rates for the total energy consumption of technical equipment. Heavy Equipment, such as construction- and agricultural machines, contributes over 80% of the total off-road diesel fuel consumption in Germany per annum. It is therefore necessary to provide helpful solutions in order to reach this ambitious aim. The German Federal Ministry of Education and Research cooperates with machine manufacturers, component suppliers and research institutes in the area of heavy equipment. Under the project name TEAM [2] a three year project has been started, which is focused on the development and integration of new propulsion and steering systems for heavy equipment. One task within the project is finding an appropriate way of evaluating the energy efficiency of the enhanced machines, after the powertrain modifications have been applied to it.

Cooling is a critical factor for improving power density in electrical appliances, especially in integrated drives for mobile applications. However, the issue of distributed losses in electric machines can lead to hotspots and temperature gradients within the electric drive. Traditional cooling jackets use unidirectional flow without or with evenly distributed cooling structures. This often aggravates the issue of hotspots, resulting in thermal derating and thus limiting the operation range. As well, a non-demand oriented distribution of cooling structures leads to unnecessary pressure losses. This problem is addressed with a newly elaborated method for distributing cooling elements, i.e., pin fins with varying density distribution inside the cooling channel. Results from previous work, numerical simulations, and measurement data from a planar test bench are used. The approach segments the cooling channel by using a loss profile.