Circuit assembly, method for producing a test voltage, and testing device for determining a loss factor, which testing device contains said circuit assembly

A method for generating a test voltage (UP) for testing a test object (2), comprising:

• (A) Generating a first high voltage (U1) with positive sign and variable amplitude at the output of a first high-voltage source (3) and a second high voltage (U2) with negative sign and variable amplitude at the output of a second high-voltage source (4), and
• (B) Successively charging and discharging the test object (2) by appropriate switching of a high-voltage switch arrangement (7) disposed between the outputs (5, 6) of the high-voltage sources (3, 4) and the test object (2), wherein a closed-loop controller (8) is provided that measures the voltage (UP) at the test object (2) and, as a function of the measured voltage (UP), acts on the high-voltage switch arrangement (7) for well-defined charging and discharging of the test object (2),
• wherein the closed-loop controller (8) does not act on the two high-voltage sources (3, 4) and that a separate open-loop controller (14) acts on the two high-voltage sources (3, 4), wherein the open-loop controller (14) generates a clock signal (T) independent of the voltage (UP) at the test object (2), so that a synchronized, predefined high voltage (U1, U2) uninfluenced by the closed-loop controller (8) is supplied by the two high-voltage sources (3, 4).