Circuit arrangement for protection against excess current input- in intermediate circuit voltage inverters

摘要

A circuit for limiting inrush current and for overvoltage protection in a voltage converter uses the drain-source path of a field-controlled semiconductor (4) to limit the charging current in a storage condenser (2) plus the voltage between the supply (1) and this condenser. The gate of the semiconductor is connected to the output of an amplifier (11) whose power supply comes from a voltage source (5). The non-inverting input of the amplifier comes from a reference voltage (12) and the inverting input comes from the node between a resistance (9) and a diode (10) which form a chain between the voltage source and earth. The diode is biased so that blocks a drain-source voltage that is bigger than the source voltage.