Circuit assembly and method for generating alternating current from a number of unregulated power supply units with output DC voltage which varies over time

The arrangement has two coils arranged in a positive branch and a negative branch of a boost converter. An anode of the positive branch connects the coils with a half bridge circuit of power transistors and diodes, and a cathode of the negative branch connects terminals of the diodes with a series circuit of capacitors. A control unit (80) has a measuring device (82) for measuring an intermediate circuit voltage of an inverter circuit (70), where the control unit is connected with control devices of uncontrolled voltage sources (10a-10n') for controlling the voltage sources. An independent claim is also included for a method for controlling a circuit arrangement.