Voltage-supply circuit arrangement for control devices of semiconductor switches which can be turned off via their control terminal

摘要

The purpose is to specify a voltage-supply circuit arrangement for a control device of semiconductor switches (H1 to H6) which can be turned off via their control terminal in the power inverter (7) of an link converter having constant intermediate-circuit voltage, which arrangement ensures inexpensive transmission of the control signals (a1 to a6) provided by a device (2), with simultaneous avoidance of a coupling between intermediate-circuit voltage and mains voltage in the voltage supply. Provided for this purpose is a power supply unit (1) which is connected to the mains (8) supplying the converter (7) and supplies the device (2) with a supply voltage (UE). Provided independently thereof is a switched-mode power supply (5) which is connected to the intermediate circuit (4) and supplies excitation amplifiers (V1 to V6) for the logic control signals (a1 to a6) output by the device (2), which amplifiers are connected upstream of the control terminals of the semiconductor switches (H1 to H6), in each case with a further supply voltage (U1 to U6). <IMAGE>