Abstract: A control element, in particular a piezoelectrically operated fuel injection valve in an internal combustion engine, is charged, in order to compensate for stochastic reactions in the internal combustion engine, with a constant nominal voltage applied to a series circuit that includes a charge capacitor and a charge reversal capacitor, and it is discharged into the charge reversal capacitor to a prescribed voltage value. The remaining residual charge of the control element is charged into the charge capacitor via a limiter path.

Abstract: A control element, in particular a piezoelectrically operated fuel injection valve in an internal combustion engine, is charged, in order to compensate for stochastic reactions in the internal combustion engine, with a constant nominal voltage applied to a series circuit that includes a charge capacitor and a charge reversal capacitor, and it is discharged into the charge reversal capacitor to a prescribed voltage value. The remaining residual charge of the control element is charged into the charge capacitor via a limiter path.

Abstract: The invention relates to a process for producing a shaped body, in which a mixture of oxidic starting powders or a superconducting material, which comprises at least 30% by volume of platelet-shaped primary particles and has such a composition that a high-temperature superconducting material is formed on later, suitable thermal treatment, is comminuted by milling, shearing and/or rolling in such a way that the comminuted powder has a powder particle size distribution having a d90 of ≦20 &mgr;m, and in which the powders which have been comminuted in this way are isostatically compacted by the dry bag method.