CIRCUIT FOR VOLTAGE STABILIZATION IN AN ONBOARD POWER SUPPLY

• US 20110012424A1
• Filed: 12/22/2008
• Published: 01/20/2011
• Est. Priority Date: 12/21/2007
• Status: Active Grant

• Current Assignee: LISA Draxlmaier GmbH
• Original Assignee: LISA Draxlmaier GmbH
• Inventors: Wortberg, Michael, Uhl, Gunter, Grohmann, Dieter
• Granted Patent: US 9,240,704 B2
• Time in Patent Office: Days
• US Class Current: 307/10.1
• CPC Class Codes: B60R 16/03 for supply of electrical power to vehicle subsystems or for circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: H02J 1/08 Three-wire systems; Systems having more than three wires
• CPC Class Codes: H02J 2310/46 for ICE-powered road vehicles
• CPC Class Codes: H02J 7/1423 with multiple batteries

Abstract

The invention relates to 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). The circuit (20, 50) comprises a diode element (24) which contains a plurality of semiconductor switches (34) connected in parallel, a pilot and control circuit (33) which 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, and a second energy store (E2) which is electrically connected to the diode element (24) and to the onboard power supply (10).

Claims

1. A circuit for voltage stabilization of an on-board motor vehicle electrical system, which is electrically connected between the on-board motor vehicle electrical system to be stabilized and a first energy storage, the circuit comprising:

a diode element comprising at least one semi-conductor switch connected in parallel;

a pilot and control circuit adapted to determine the intensity of a current flowing through the diode element and controls the at least one semi-conductor switch of the diode element on the basis of the determined current intensity; and

a second energy storage electrically connected to the diode element and to the on-board motor vehicle electrical system.

2. The circuit according to claim 1, wherein the diode element further comprises a Schottky diode connected in parallel to the at least one semi-conductor switch.

3. The circuit according to claim 1, wherein the second energy storage is a battery connected via a switching unit.

4. The circuit according to claim 3, wherein the switching unit comprises two inversely arranged semi-conductor switches connected in series.

5. The circuit according to claim 4, wherein the switching unit further comprises a micro-controller for controlling the semi-conductor switches of the switching unit.

6. The circuit according to claim 5, wherein the micro-controller is adapted to monitor the temperature of the semi-conductor switches of the diode element.

7. The circuit according to claim 3, further comprising a device adapted to test the charge condition of the battery.

8. The circuit according to claim 1, wherein the second energy storage is a super capacitor.

9. The circuit according to claim 1, wherein the semi-conductor switches of the diode element are field effect transistors, preferably metal oxide semi-conductor field effect transistors (MOSFETs).

10. The circuit according to claim 1, wherein the circuit is electrically connected between the motor vehicle on-board electrical system to the stabilized and one or a plurality of a high-current consumer load connected to a first energy storage.

11. The circuit according to claim 10, wherein one of the high-current consumer loads is one of a start-stop function, an electronic power steering system, and an electro-hydraulic brake.

12. The circuit according to claim 1, in combination with a motor vehicle.

13. The circuit according to claim 2, wherein the diode is a Schottky diode.

14. The circuit according to claim 4, wherein the each of the two inversely arranged switches comprises field effect transistors.

15. The circuit according to claim 7, wherein the device is adapted to measure an impedence of the battery.

16. The circuit according to claim 1, wherein the semi-conductor switches of the diode element are MOSFETs.

17. The combination according to claim 12, wherein the motor vehicle is an automobile.