Method for Controlling a Battery System, a Battery System, and Motor Vehicle

• US 20140028088A1
• Filed: 07/24/2013
• Published: 01/30/2014
• Est. Priority Date: 07/25/2012
• Status: Abandoned Application

• Current Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Original Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Inventors: Salziger, Jan, Rischen, Joachim, Anzicek, Joshua
• Application Number:
  US13/949,344
• Publication Number:
  US 20140028088A1
• Time in Patent Office: Days
• US Class Current: 307/9.1
• CPC Class Codes: B60R 16/02 electric constitutive elements
• 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: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: H02J 2310/46 for ICE-powered road vehicles
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A battery system comprises at least one battery cell and a high-voltage network connected thereto which includes a pre-charge circuit having at least one pre-charge resistor. The battery system further comprises a component including a link capacitor with a specific capacitance. A method for controlling the battery system includes measuring a first voltage at the link capacitor before charging, charging the link capacitor, and measuring a second voltage at the link capacitor after charging. The method further includes forming a voltage difference from the first and the second voltage, and determining an energy received by the pre-charge resistor based on the voltage difference at the link capacitor and based on the capacitance of the link capacitor.

Claims

1. A method for controlling a battery system including at least one battery cell and a high-voltage network connected to the at least one battery cell, the high-voltage network including a pre-charge circuit having at least one pre-charge resistor, and a component having a link capacitor with a specific capacitance, the method comprising:

measuring a first voltage at the link capacitor before charging the link capacitor;

charging the link capacitor;

measuring a second voltage at the link capacitor after charging the link capacitor;

forming a voltage difference from the first voltage and second voltage; and

determining an energy received by the pre-charge resistor based on the voltage difference at the link capacitor and further based on the specific capacitance of the link capacitor.

2. The method according to claim 1, further comprising:

determining an energy W_w.c. received by the pre-charge resistor in a worst-case scenario in accordance with;

3. The method according to claim 1, further comprising:

determining a heat energy output by the pre-charge resistor.

4. The method according to claim 3, further comprising:

determining a maximum power over a specific period of time for the pre-charge resistor based on (i) a thermal loadability of the pre-charge resistor, and (ii) the heat energy output by the pre-charge resistor.

5. The method according to claim 1, further comprising:

predicting a charging curve of the link capacitor.

6. The method according to claim 5, further comprising:

measuring the charging curve of the link capacitor; and

comparing the predicted charging curve with the measured charging curve.

7. The method according to claim 6, further comprising:

determining a fault in the event of a deviation between the predicted charging curve and the measured charging curve.

8. The method according to claim 1, further comprising:

discharging the link capacitor via a discharge circuit which includes a discharge relay and a discharge resistor.

9. A battery system comprising:

a battery management unit configured to carry out a method for controlling the battery system,

wherein the method includes

measuring a first voltage at a link capacitor before charging the link capacitor,

charging the link capacitor,

measuring a second voltage at the link capacitor after charging the link capacitor,

forming a voltage difference from the first voltage and second voltage, and

determining an energy received by a pre-charge resistor based on the voltage difference at the link capacitor and further based on a capacitance of the link capacitor.

10. The battery system according to claim 9, further comprising:

at least one battery cell;

a high-voltage network connected to the at least one battery cell, the high-voltage network including a pre-charge circuit with an operational contactor, a first series circuit formed from a pre-charge contactor, and the pre-charge resistor, the first series circuit being connected in parallel to the operational contactor;

a component including the link capacitor, the pre-charge circuit and the component forming a second series circuit with the at least one battery cell; and

a discharge circuit including a discharge relay and a discharge resistor connected in series to the discharge relay, the discharge circuit being connected in parallel to the link capacitor.

11. A motor vehicle comprising:

a drive system; and

a battery system connected to the drive system, the battery system including (i) at least one battery cell, (ii) a high-voltage network connected to the at least one battery cell, the high-voltage network including a pre-charge circuit with an operational contactor, a first series circuit formed from a pre-charge contactor, and a pre-charge resistor, the first series circuit being connected in parallel to the operational contactor, (iii) a component including a link capacitor, the pre-charge circuit and the component forming a second series circuit with the at least one battery cell, and (iv) a discharge circuit including a discharge relay and a discharge resistor connected in series to the discharge relay, the discharge circuit being connected in parallel to the link capacitor; and

a battery management unit configured to carry out a method for controlling the battery system, the method including (i) measuring a first voltage at the link capacitor before charging the link capacitor, (ii) charging the link capacitor, (iii) measuring a second voltage at the link capacitor after charging the link capacitor, (iv) forming a voltage difference from the first voltage and second voltage, and (v) determining an energy received by the pre-charge resistor based on the voltage difference at the link capacitor and further based on a capacitance of the link capacitor.