Drive system for a motor vehicle comprising an internal combustion engine and an electric motor

• US 8,097,975 B2
• Filed: 04/17/2003
• Issued: 01/17/2012
• Est. Priority Date: 05/24/2002
• Status: Expired due to Fees

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler AG (Mercedes-Benz Group AG)
• Inventors: Bosch, Hermann, Brinkmeyer, Horst, Kemmler, Roland, Krauss, Markus, Sahm, Ing. Dietrich, Wolf, Hans-Christoph, Heni, Anton
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Amrany, Adi
• Application Number:
  US10/515,231
• Publication Number:
  US 20080220932A1
• Time in Patent Office: 3,197 Days
• Field of Search: 307/9.1, 307/10.1, 307/10.6
• US Class Current: 307/10.1
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 6/28 characterised by the electric energy storing means, e.g. batteries or capacitors
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 1/00 Supplying electric power to auxiliary equipment of vehicles circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0866 comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 2011/0885 Capacitors, e.g. for additional power supply
• CPC Class Codes: F02N 2011/0888 DC/DC converters
• CPC Class Codes: F02N 2011/0896 Inverters for electric machines, e.g. starter-generators
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• 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

Abstract

The invention relates to an apparatus and a method for starting an internal combustion engine for a motor vehicle, wherein the internal combustion engine has an associated electrical machine (1) which is operated as a starter/generator. During starting, the electrical machine (1) is supplied with a voltage which is obtained from addition or from subtraction of the voltages which are produced on a first energy store (3) and the voltages which are produced on a second energy store (4).

Claims

1. A drive system for a motor vehicle comprising:

an internal combustion engine, the internal combustion engine having an associated electrical machine which can be operated as a starter/generator,

a first energy store having a first pole interconnected by a first line to both a bidirectional DC/DC converter and a switching unit, and a second pole interconnected by a second line to said switching unit, said bidirectional DC/DC converter, and an electrical vehicle power supply system of the motor vehicle having electrical loads utilized during motor vehicle operation,

an inverter interposed between said electrical machine and said switching unit, and

a second energy store having a first pole interconnected by said second line to the switching unit, the second pole of the first energy store, the bidirectional DC/DC converter, and the electrical vehicle power supply system of the motor vehicle,

wherein the bidirectional DC/DC converter is arranged in parallel with the first energy store,

wherein the switching unit contains a first semiconductor switch and a first diode between the inverter and the first line and a second semiconductor switch and a second diode between the inverter and the second line, and

wherein said second pole of the first energy store and said first pole of the second energy store are at a common potential.

2. The drive system as claimed in claim 1, wherein the first pole of the second energy store is at a positive potential, and the second pole of the second energy store is at a negative potential or ground.

3. The drive system as claimed in claim 1, wherein the common potential is formed by the motor vehicle bodywork.

4. The drive system as claimed in claim 3, wherein said first energy store produces a higher current than the second energy store.

5. The drive system as claimed in claim 1, wherein said switching unit is provided between the inverter and the first energy store.

6. The drive system as claimed in claim 1, wherein the first energy store comprises a super capacitor.

7. The drive system as claimed in claim 1, wherein said first energy store produces a higher current than the second energy store.

8. The drive system as claimed in claim 1, wherein said switching unit is a first switching unit, and further comprising a second switching unit disposed between the inverter and said first switching unit, said first energy store, said bidirectional DC/DC converter, said energy store, and said electric vehicle power supply system.