Hybrid drive system and method for adjusting a hybrid drive system

• US 20050000741A1
• Filed: 07/17/2002
• Published: 01/06/2005
• Est. Priority Date: 08/02/2001
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Ruppert, Swen, Holl, Eugen
• Granted Patent: US 7,221,062 B2
• Time in Patent Office: Days
• US Class Current: 180/65.220
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 2200/18 Buses
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• 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

Abstract

A hybrid drive system is for a vehicle and includes an intermediate circuit and an energy accumulator. The energy accumulator is connected to the intermediate circuit by way of a diode, whereby a transistor enabling current to flow in an opposite direction is connected parallel thereto. The transistor is placed in a blocking position in order to discharge the energy accumulator and the diode enables current to pass. If the energy accumulator is not used, the diode is also blocked by increasing the voltage of the intermediate circuit with the aid of the voltage on the energy accumulator. In order to charge the energy accumulator, the transistor is conductingly switched. The diode does not allow the current to pass in this direction.

Claims

1. A method for controlling a hybrid drive system for a vehicle with an intermediate circuit and an energy accumulator, the energy accumulator being connected to the intermediate circuit via a switch, the switch including a diode with a forward direction toward the intermediate circuit and a transistor, adapted to be turned on and off, arranged parallel to the diode and including a forward direction toward the energy accumulator, wherein the transistor is turned off and the diode is forward-biased for discharging the energy accumulator and the transistor is turned on and the diode is reverse-biased for charging the energy accumulator, the method comprising:

turning off the transistor; and

increasing the voltage across the intermediate circuit until the voltage is greater than the voltage across the energy accumulator, to thereby disconnect the energy accumulator when it is neither to be charged nor discharged.

3. The method as claimed in claim 1, wherein the voltage across the intermediate circuit is increased during a driving mode up to the operating point of the hybrid drive system.

4. The method as claimed in claim 1, wherein, to charge the energy accumulator, the voltage across the intermediate circuit is brought to the level of the voltage across the energy accumulator and then the transistor is turned on.

6. The method as claimed in claim 1, wherein the energy accumulator is an ultracapacitor.

7. The method as claimed in claim 3, wherein, to charge the energy accumulator, the voltage across the intermediate circuit is brought to the level of the voltage across the energy accumulator and then the transistor is turned on.

8. The method as claimed in claim 4, wherein controlling of the voltage across the intermediate circuit, to bring it to the level of the voltage across the energy accumulator, occurs at the same time as a transition from a driving mode to a braking mode.

9. The method as claimed in claim 7, wherein controlling of the voltage across the intermediate circuit, to bring it to the level of the voltage across the energy accumulator, occurs at the same time as a transition from the driving mode to a braking mode.

11. The method as claimed in claim 3, wherein the energy accumulator is an ultracapacitor.

12. The method as claimed in claim 4, wherein the energy accumulator is an ultracapacitor.

14. The method as claimed in claim 7, wherein the energy accumulator is an ultracapacitor.

15. The method as claimed in claim 8, wherein the energy accumulator is an ultracapacitor.

16. The method as claimed in claim 9, wherein the energy accumulator is an ultracapacitor.

2. A method for controlling a hybrid drive system for a vehicle with an intermediate circuit and an energy accumulator, the energy accumulator being connected to the intermediate circuit via a switch, the switch including a diode with a forward direction toward the intermediate circuit and a transistor, adapted to be turned on and off, arranged parallel to the diode and including a forward direction toward the energy accumulator, wherein the transistor is turned off and the diode is forward-biased for discharging the energy accumulator and the transistor is turned on and the diode is reverse-biased for charging the energy accumulator, that the method comprising:

turning the transistor off and blocking the diode, to disconnect the energy accumulator when it is neither to be charged nor discharged; and

bringing the voltage across the intermediate circuit to a level of the voltage across the energy accumulator and then turning the transistor on to charge the energy accumulator.

5. The method as claimed in claim 2, wherein controlling of the voltage across the intermediate circuit, to bring it to the level of the voltage across the energy accumulator, occurs at the same time as a transition from driving mode to a braking mode.

10. The method as claimed in claim 2, wherein the energy accumulator is an ultracapacitor.

13. The method as claimed in claim 5, wherein the energy accumulator is an ultracapacitor.