Inverter for an electric machine and method for operating an inverter for an electric machine

• US 9,676,277 B2
• Filed: 08/03/2010
• Issued: 06/13/2017
• Est. Priority Date: 09/24/2009
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schwarz, Albrecht, Haas, Axel, Heil, Matthias
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Dhillon, Jagdeep
• Application Number:
  US13/498,094
• Publication Number:
  US 20130033908A1
• Time in Patent Office: 2,506 Days
• Field of Search: 307 65, 307 91, 307 80, 307 43, 307112, 307 101- 106, 180 6521, 180 6531, 180 6551, 363 15, 363 34, 363 40, 363 44, 363 71, 363132, 318139, 318140, 318143
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 3/0092 with use of redundant elements for safety purposes
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 7/14 for vehicles propelled by ac motors
• CPC Class Codes: H02M 1/10 Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

An inverter for an electric machine as well as a method for operating an inverter for an electric machine. In this context, the inverter has at least one output stage unit for producing a connection between the electric machine and a power supply network, a control unit for controlling the at least one output stage unit, a supply unit independent of the power supply network for the power supply of the output stage unit(s), at least one emergency operation control assigned to the output stage unit(s) for controlling the output stage unit(s) in the fault case, as well as at least one emergency operation supply assigned to the output stage unit(s) for generating a power supply for the output stage unit(s) from the power supply network in the fault case.

Claims

1. An inverter for an electric machine configured to be selectively operated as at least one of a motor and a generator for a hybrid vehicle, comprising:

at least one output stage unit for producing a connection between the electric machine configured to be selectively operated as at least one of a motor and a generator and a power supply network;

a control unit for controlling the at least one output stage unit;

a supply unit, which is independent of the power supply network, for the power supply of the at least one output stage unit;

at least one emergency operation control assigned to the at least one output stage unit for controlling the at least one output stage unit in the fault case; and

at least one emergency operation supply assigned to the at least one output stage unit for generating a power supply for the at least one output stage unit from the power supply network in the fault case;

wherein if the electric machine is selectively operated in a motor operation, the electric machine is supplied with power from the power supply network, and wherein if the electric machine is selectively operated in a generator operation, the electric machine, in reverse, feeds electrical power into the power supply network.

2. The inverter of claim 1, wherein the at least one emergency operation control monitors operating parameters within the inverter and diagnoses a fault case if at least one of the operating parameters lies below a specified lower threshold value or above a specified upper threshold value.

3. The inverter of claim 1, wherein the at least one emergency operation supply is switchable on and off.

15. The inverter of claim 1, wherein a fault case is diagnosed by evaluation of operating parameters within the inverter, and wherein the emergency operation control controls the respective output stage unit so that switching elements within the output stage unit are switched to a short-circuit operation.

16. The inverter of claim 1, wherein a fault case is diagnosed by evaluation of operating parameters within the inverter, wherein the emergency operation control controls the respective output stage unit so that an overvoltage in the power supply network is prevented, and wherein the emergency operation control controls the respective output stage unit so that switching elements within the output stage unit are switched to a short-circuit operation.

4. A method for operating an inverter for an electric machine configured to be selectively operated as at least one of a motor and a generator for a hybrid vehicle, the method comprising:

producing via the inverter and at least one output stage unit thereof a connection between the electric machine configured to be selectively operated as at least one of a motor and a generator and a power supply network, in which, in normal operation, the at least one output stage unit is supplied with power via a supply unit that is independent of the power supply network;

controlling the at least one output stage via a control unit; and

in a fault case, generating power for the power supply of the at least one output stage unit from the power supply network by at least one emergency operation supply and controlling the at least one output stage unit by at least one emergency operation control;

wherein if the electric machine is selectively operated in a motor operation, the electric machine is supplied with power from the power supply network, and wherein if the electric machine is selectively operated in a generator operation, the electric machine, in reverse, feeds electrical power into the power supply network.

5. The method of claim 4, wherein a fault case is diagnosed by evaluation of operating parameters within the inverter.

6. The method of claim 5, wherein a fault case is diagnosed if at least one of the operating parameters lies below a specified lower threshold value or above a specified upper threshold value.

7. The method of claim 4, wherein the at least one emergency operation supply is switched on after the diagnosis of a fault case.

8. The method of claim 7, wherein the at least one emergency operation supply is switched off again, as soon as no fault case is diagnosed any longer.

9. The method of claim 4, wherein the emergency operation control controls the respective output stage unit so that an overvoltage in the power supply network is prevented.

10. The method of claim 9, wherein the emergency operation control controls the respective output stage unit so that switching elements within the output stage unit are switched to a short-circuit operation.

11. The method of claim 10, wherein the emergency operation control controls the respective output stage unit so that an overcurrent in the output stage is prevented.

12. The method of claim 11, wherein, in response to a diagnosis of an overcurrent the switching into the short-circuit operation is not prevented or a short-circuit operation is broken off.

13. The method of claim 4, wherein a fault case is diagnosed by evaluation of operating parameters within the inverter, and wherein the emergency operation control controls the respective output stage unit so that switching elements within the output stage unit are switched to a short-circuit operation.

14. The method of claim 4, wherein a fault case is diagnosed by evaluation of operating parameters within the inverter, wherein the emergency operation control controls the respective output stage unit so that an overvoltage in the power supply network is prevented, and wherein the emergency operation control controls the respective output stage unit so that switching elements within the output stage unit are switched to a short-circuit operation.