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Recently, hybrid and fully electric drives have been developing widely in variety, power and range. The new reliable simulation approaches are needed, in order to meet the defined NVH targets of these systems and implementing CAE methods for front loading, Design Validation Process (DVP). This paper introduces the application of a novel NVH analysis workflow on an electric vehicle driveline including both electromagnetic and mechanical excitations for an absolute evaluation of the NVH performance. At first, the electromagnetic field is simulated using FEM method to extract the excitations on the stator, rotor bearings as well as the drive torque. Then, the multibody dynamic model of the driveline is built-up, driven by this torque. The effect of eccentricity and skew angle of rotor in electromagnetic excitations are shown.

The design of a cam profile and its effect on the dynamic performance of the operated mechanisms has long been a centre of attention. Cam profile has been known as one of the most important parameters which can directly affect engine performance and the mean gas temperature. Valve timing overlap in turbocharged heavy duty diesel engines can exceed to 120 degrees and even more. In addition, in these types of engine, need for increase the exhaust and inlet valve opening time by dwelling individuates cam design basis of these engines. Two main issues which restrict the cam design are piston strike and maximum negative acceleration which can lead to contact loss. Higher inertia force due to the heavier valvetrain parts in heavy duty diesel engines would increase inertia forces that can aggravate contact loss in system. In this paper, the valvetrain of a heavy duty medium speed diesel engine under development has been studied.