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For automotive applications other optimization criteria have to be considered than for conventional industrial drives. Especially volume and environmental conditions such as e.g. temperature have major influence on the selection of components. The paper describes the evaluation of AC current and voltage ripple in DC-link capacitors which both restrict the possibilities of miniaturisation of these components. Aluminium electrolytic capacitors are standard components for the DC-bus of voltage source DC-link inverters (VSI) which provide very good capacity to volume and capacity to cost ratios. Film capacitors combine good ac current to volume ratio with rather poor capacity to volume ratio. In the paper analytical calculations simulations and experimental results are described which show possibilities to reduce the required DC-link capacity of VSI which is a prerequisite for the economic usage of film capacitors. It is shown that the voltage ripple in the DC-link of a VSI increases with higher output currents and higher modulation index of the PWM and decreases with higher carrier frequencies of the PWM and higher capacity values of the DC-link.