Circuit for voltage stabilization in an onboard power supply

摘要

A circuit (20, 50) for voltage stabilization in an onboard power supply (10), particularly for motor vehicles, which is electrically connected between the onboard power supply (10) to be stabilized and a first energy store (E1) is disclosed. The circuit (20, 50) includes a diode element (24) which contains a plurality of semiconductor switches (34) connected in parallel. The circuit (20, 50) also includes a pilot and control circuit (33). The control circuit (33) determines the level of a current flowing through the diode element (24) and controls the semiconductor switches (34) of the diode element (24) on the basis of the determined current level. The circuit (20, 50) includes a second energy store (E2) which is electrically connected to the diode element (24) and to the onboard power supply (10).

主权项

1. A circuit for voltage stabilization of an on-board motor vehicle electrical system, the circuit comprising:
a diode element comprising a plurality of first semi-conductor switches connected in parallel, wherein the diode element is configured and arranged to allow current flow only in a direction from an energy storage towards the on-board motor vehicle electrical system; a pilot and control circuit configured to determine an intensity of a current flowing through the diode element and to control said plurality of first semi-conductor switches of the diode element based on the determined current intensity in such manner that said plurality of first semi-conductor switches allow a current flow from the energy storage to the on-board motor vehicle electrical system, but block a current flow from the on-board motor vehicle electrical system to the energy storage; a battery electrically connected to the diode element and connectable to the on-board motor vehicle electrical system; and a switching unit connecting the battery to the on-board motor vehicle electrical system, the switching unit including:
two inversely arranged second semi-conductor switches connected in series; anda micro-controller for controlling the second semi-conductor switches, the micro-controller being configured to:
determine a voltage and a temporal voltage drop across the second semi-conductor switches, andturn on the second semi-conductor switches such that the battery supplies power to the on-board electrical system if:
the voltage across the second semi-conductor switches is smaller than a normal operating voltage of the on-board electrical system, andthe temporal voltage drop across the second semi-conductor switches exceeds a predetermined rate, wherein the circuit is electrically connected between the on-board motor vehicle electrical system and the energy storage and wherein the circuit is electrically connected between the onboard motor vehicle electrical system and a starter, the circuit being adapted to stabilize the onboard motor vehicle electrical system.