SYSTEMS AND METHODS FOR DEACTIVATING A MATRIX CONVERTER

• US 20110227407A1
• Filed: 03/16/2010
• Published: 09/22/2011
• Est. Priority Date: 03/16/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: RANSOM, RAY M.
• Granted Patent: US 8,410,635 B2
• Time in Patent Office: Days
• US Class Current: 307/9.1
• CPC Class Codes: B60L 3/00 Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption methods or circuit arrangements for monitoring or controlling batteries or fuel cells B60L58/00
• CPC Class Codes: B60L 53/20 characterised by converters located in the vehicle
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: H02M 1/36 Means for starting or stopping converters
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• 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 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

Systems and methods are provided for deactivating a matrix conversion module. An electrical system comprises an alternating current (AC) interface, a matrix conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the matrix conversion module, and a control module. The control module is coupled to the matrix conversion module, and in response to a shutdown condition, the control module is configured to operate the matrix conversion module to deactivate the first conversion module when a magnitude of a current through the inductive element is less than a threshold value.

Claims

1. An electrical system comprising:

an alternating current (AC) interface;

a first conversion module coupled to the AC interface;

an inductive element coupled between the AC interface and the first conversion module; and

a control module coupled to the first conversion module, wherein in response to a shutdown condition, the control module is configured to deactivate the first conversion module when a magnitude of a current through the inductive element is less than a threshold value.

2. The electrical system of claim 1, wherein when the magnitude of the current through the inductive element is less than the threshold value, the control module is configured to operate the first conversion module to discharge the inductive element prior to deactivating the first conversion module.

3. The electrical system of claim 2, wherein in response to the shutdown condition, the control module is configured to operate the first conversion module with a shutdown duty cycle.

4. The electrical system of claim 3, the first conversion module comprising a plurality of switching elements, wherein the control module is configured to operate the first conversion module with the shutdown duty cycle by:

generating pulse-width modulation (PWM) command signals having a reduced duty cycle; and

operating the plurality of switching elements in accordance with the PWM command signals.

5. The electrical system of claim 3, further comprising:

a direct current (DC) interface;

a second conversion module; and

an isolation module coupled between the first conversion module and the second conversion module, the isolation module providing galvanic isolation between the first conversion module and the second conversion module.

6. The electrical system of claim 5, the shutdown duty cycle being equal to 1−

U, wherein U is governed by the equation

7. The electrical system of claim 1, wherein the first conversion module comprises:

a first node coupled to the inductive element;

a second node coupled to the AC interface;

a third node;

a fourth node;

a first switch coupled between the first node and the third node, the first switch being configured to allow current from the third node to the first node when the first switch is closed;

a second switch coupled between the first switch and the third node, the second switch being configured to allow current from the first node to the third node when the second switch is closed;

a third switch coupled between the first node and the fourth node, the third switch being configured to allow current from the fourth node to the first node when the third switch is closed;

a fourth switch coupled between the third switch and the fourth node, the fourth switch being configured to allow current from the first node to the fourth node when the fourth switch is closed;

a fifth switch coupled between the second node and the fourth node, the fifth switch being configured to allow current from the second node to the fourth node when the fifth switch is closed;

a sixth switch coupled between the fifth switch and the second node, the sixth switch being configured to allow current from the fourth node to the second node when the sixth switch is closed;

a seventh switch coupled between the second node and the third node, the seventh switch being configured to allow current from the second node to the third node when the seventh switch is closed; and

an eighth switch coupled between the seventh switch and the second node, the eighth switch being configured to allow current from the third node to the second node when the eighth switch is closed.

8. The electrical system of claim 7, wherein the control module is configured to operate the first conversion module to provide an electrical connection between the first node and the second node to discharge the inductive element when current through the inductive element is less than the threshold value prior to deactivating the first conversion module.

9. The electrical system of claim 8, wherein the control module is configured to provide the electrical connection between the first node and the second node by concurrently closing the first switch, the second switch, the seventh switch, and the eighth switch.

10. The electrical system of claim 8, wherein the control module is configured to provide the electrical connection between the first node and the second node by concurrently closing the third switch, the fourth switch, the fifth switch, and the sixth switch.

11. The electrical system of claim 8, wherein the control module is configured to deactivate the first conversion module by opening the first switch, the second switch, the third switch, the fourth switch, the fifth switch, the sixth switch, the seventh switch, and the eighth switch after provide the electrical connection between the first node and the second node.

12. A method for controlling an electrical system including a first conversion module and an inductive element configured electrically in series between the first conversion module and an AC interface, the method comprising:

operating the first conversion module to achieve a desired flow of energy from the AC interface;

identifying a shutdown condition; and

in response to identifying the shutdown condition;

monitoring current through the inductive element; and

when a magnitude of the current through the inductive element is less than a threshold value, deactivating the first conversion module.

13. The method of claim 12, further comprising operating the first conversion module to discharge the inductive element when the magnitude of the current through the inductive element is less than the threshold value prior to deactivating the first conversion module.

14. The method of claim 13, further comprising monitoring voltage at the AC interface, wherein the first conversion module is operated to discharge the inductive element when the magnitude of the current through the inductive element is less than the threshold value and a magnitude of the voltage at the AC interface is less than a second threshold value.

15. The method of claim 12, further comprising operating a plurality of switches of the first conversion module in accordance with pulse-width modulation (PWM) command signals having a shutdown duty cycle in response to the shutdown condition.

16. The method of claim 15, the electrical system including a direct current (DC) interface, a second conversion module, and an isolation module coupled between the first conversion module and the second conversion module, the isolation module providing galvanic isolation between the first conversion module and the second conversion module, wherein operating the first conversion module using the shutdown duty cycle further comprises calculating the shutdown duty cycle based at least in part on a voltage at the AC interface and an effective resistance at the DC interface.

17. A vehicle electrical system comprising:

a DC interface configured to be coupled to a DC energy source;

an AC interface configured to be coupled to an AC energy source;

an energy conversion module coupled to the DC interface;

a matrix converter coupled to the AC interface;

an inductive element configured electrically in series between a first node of the AC interface and the matrix converter;

an isolation module coupled between the energy conversion module and the matrix converter, the isolation module providing galvanic isolation between the energy conversion module and the matrix converter; and

a control module coupled to the matrix converter, wherein the control module is configured to;

operate the matrix converter to deliver energy from the AC interface to the DC interface;

identify a shutdown condition; and

in response to identifying the shutdown condition;

operate the matrix converter in accordance with a shutdown duty cycle;

operate the matrix converter to discharge the inductive element when a magnitude of a current through the inductive element is less than a threshold value; and

deactivate the matrix converter after discharging the inductive element.

18. The vehicle electrical system of claim 17, wherein the shutdown duty cycle is equal to 1−

U, wherein U is governed by the equation

19. The vehicle electrical system of claim 17, the AC interface having a second node coupled to the matrix converter and the matrix converter including a plurality of switches configured between a third node coupled to the inductive element and the second node, wherein the control module is configured to operate the matrix converter to discharge the inductive element by operating the plurality of switches to provide an electrical connection between the second node and the third node.

20. The vehicle electrical system of claim 19, wherein the control module is configured to operate the matrix converter in accordance with the shutdown duty cycle by operating the plurality of switches in accordance with pulse-width modulation (PWM) command signals having the shutdown duty cycle.