Method and device for diagnosing a discharge circuit of an electrical system

• US 9,651,612 B2
• Filed: 03/27/2013
• Issued: 05/16/2017
• Est. Priority Date: 03/27/2012
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Soell, Max, Wahl-Raabe, Ellen
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): Nasir, Taqi
• Application Number:
  US13/851,506
• Publication Number:
  US 20130257446A1
• Time in Patent Office: 1,511 Days
• Field of Search: 324503, 324506, 324510, 324511, 324512, 324522, 324526, 324429, 324414, 324404, 324133
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 3/0007 Measures or means for preventing or attenuating collisions
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 50/72 Constructional details of fuel cells specially adapted for electric vehicles
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/28 Testing of electronic circuits, e.g. by signal tracer EMC, EMP or similar testing of electronic circuits G01R31/002; testing for short-circuits, discontinuities, leakage or incorrect line connection G01R31/50; checking computers or computer components G06F11/00; checking static stores for correct operation G11C29/00 ; testing receivers or transmitters of transmission systems H04B17/00
• CPC Class Codes: G01R 31/2827 Testing of electronic protection circuits testing switches G01R31/327; checking alarm systems G08B29/00; self test of summation current transformers H02H3/335
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A method and an apparatus for diagnosing a discharge circuit, wherein provision is made for the discharge circuit for discharging an electrical system, in particular for discharging an electrical system of a vehicle capable of being electrically driven. In order to achieve this end, means are provided which partially discharge the electrical system by means of said discharge circuit in a procedural step for diagnosing said discharge circuit.

Claims

1. A method for diagnosing a discharge circuit in an electrical system of a vehicle capable of being electrically driven, the method comprising:

measuring a voltage of the electrical system while partially discharging the electrical system by the discharge circuit;

determining an amount of change of the measured voltage of the electrical system changes occurring partially discharging the electrical system by the discharge circuit;

determining a difference amount between the amount of change and a predefined value; and

recognizing the discharge circuit is defective when the difference amount is greater than a predefined threshold.

2. The method according to claim 1, wherein the discharge circuit is a first discharge circuit, and wherein the method further comprises partially discharging the electrical system by a second discharge circuit before partially discharging the electrical system by the first discharge circuit.

3. The method according to claim 2, wherein the method further comprises discharging the electrical system by the second discharge circuit after partially discharging the electrical system by the first discharge circuit.

4. The method according to claim 1, wherein the discharge circuit is a first discharge circuit, and wherein the method further comprises discharging the electrical system by a second discharge circuit after partially discharging the electrical system by the first discharge circuit.

5. The method according to claim 1, wherein the method further comprises partially discharging the electrical system by the discharge circuit for a predefined time period of 200 milliseconds to 500 milliseconds.

6. The method according to claim 1, wherein the method further comprises partially discharging the electrical system by the discharge circuit such that approximately 5% of a charge contained in the electrical system is discharged by the discharge circuit.

7. The method according to claim 1, wherein the method further comprises partially discharging the electrical system by the discharge circuit such that the voltage of the electrical system is less than 170 volts.

8. The method according to claim 1, wherein the method further comprises discharging the electrical system by the discharge circuit if a defect is present within the electrical system.

9. The method according to claim 1, wherein the method further comprises

partially discharging the electrical system by the discharge circuit during a start of a trip with the vehicle, and

partially discharging the electrical system by the discharge circuit during a completion of the trip with the vehicle.

10. An apparatus for diagnosing a discharge circuit in an electrical system of a vehicle capable of being electrically driven, the apparatus comprising:

a control device configured to;

measure a voltage of the electrical system while partially discharging the electrical system by the discharge circuit,

determine an amount of change of the measured voltage of the electrical system occurring while partially discharging the electrical system by the discharge circuit,

determine a difference amount between the amount of change and a predefined value, and

recognize the discharge circuit is defective when the difference amount is greater than a predefined threshold.

11. The apparatus for diagnosing a discharge circuit according to claim 10, wherein the discharge circuit is configured such that the discharge circuit is defective after carrying out approximately 30 discharge cycles.

12. The apparatus for diagnosing a discharge circuit according to claim 10, wherein the discharge circuit is a first discharge circuit, wherein the control device is further configured to partially discharge the electrical system by a second discharge circuit before partially discharging the electrical system by the first discharge circuit.

13. The apparatus for diagnosing a discharge circuit according to claim 12, wherein the control device is further configured to further discharge the electrical system by the second discharge circuit after partially discharging the electrical system by the first discharge circuit.

14. The apparatus for diagnosing a discharge circuit according to claim 10, wherein the discharge circuit is a first discharge circuit, wherein the control device is further configured to partially discharge the electrical system by a second discharge circuit after partially discharging the electrical system by the first discharge circuit.

15. The apparatus for diagnosing a discharge circuit according to claim 10, wherein the electrical system includes a drive train.