System for charging electrical storage device and method of making same

• US 9,520,741 B2
• Filed: 11/28/2011
• Issued: 12/13/2016
• Est. Priority Date: 11/28/2011
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Kanakasabai, Viswanathan
• Primary Examiner(s): Rodas, Richard Isla
• Assistant Examiner(s): Dibenedetto, Michael
• Application Number:
  US13/304,791
• Publication Number:
  US 20130134924A1
• Time in Patent Office: 1,842 Days
• Field of Search: 320/103, 320/104, 307149-152, 180/65.1
• US Class Current: 1/1
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 2200/22 Microcars, e.g. golf cars
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/622 by satellite navigation
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: B60L 7/14 for vehicles propelled by ac motors
• CPC Class Codes: H02J 1/08 Three-wire systems; Systems having more than three wires
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: H02J 7/1438 in combination with power supplies for loads other than batteries
• CPC Class Codes: H02M 1/009 having two or more independently controlled outputs for DC-DC converter with intermediate AC H02M3/33561
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 3/335 using semiconductor devices only
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing

Abstract

A system for charging an electrical storage device includes a motor drive, a DC link electrically coupled to the motor drive, and a first leg coupled to the DC link that includes a first power switch coupled in series with a second power switch via a first node. A first inductor is coupled to the first node, and a first energy storage device (ESD) is electrically coupled to the first inductor. A second leg is coupled to the DC link that includes a third power switch coupled in series with a fourth power switch via a second node. A charging circuit includes a transformer coupled to the first and second nodes. A second ESD is coupled to receive charging energy from the transformer, and a controller is configured to cause a first voltage mismatch between the first and second nodes to generate the charging energy.

Claims

1. A propulsion system comprising:

a motor drive;

a direct current (DC) link electrically coupled to the motor drive;

a first leg coupled to the DC link and comprising a first power switch coupled in series with a second power switch via a first node;

a first inductor coupled to the first node, wherein the first leg and inductor form a first bi-directional DC-DC voltage converter;

a first energy storage device (ESD) electrically coupled to the first inductor;

a second leg coupled to the DC link and comprising a third power switch coupled in series with a fourth power switch via a second node;

a second inductor coupled to the second node, wherein the second leg and second inductor form a second bi-directional DC-DC voltage converter;

a charging circuit comprising a transformer having a first terminal coupled to the first node and having a second terminal coupled to the second node;

a second ESD coupled to receive charging energy from the transformer; and

a controller coupled to the first and second legs and configured to cause a first variable voltage difference between the first and second nodes during an interleave duration of a frequency period to generate the charging energy, wherein the second ESD can be charged during operation of the motor drive.

2. The propulsion system of claim 1 wherein the controller is further configured to vary the interleave duration based on a desired amount of the charging energy to be supplied to the second ESD.

3. The propulsion system of claim 1 wherein the first ESD has a higher voltage capacity than the second ESD.

4. The propulsion system of claim 1 wherein the first ESD is electrically coupled to the second inductor.

5. The propulsion system of claim 4 wherein the controller, in being configured to cause the first voltage difference, is configured to operate the first and second legs in a boost mode to boost a voltage of the first ESD to the DC link.

6. The propulsion system of claim 1 wherein the controller is further configured to cause a voltage match between the first and second nodes to eliminate the charging energy.

7. The propulsion system of claim 6 wherein the controller is further configured to cause a second voltage difference between the first and second nodes during the frequency period to generate the charging energy, wherein the first and second voltage differences have a duration equal to the interleave duration.

8. The propulsion system of claim 1 wherein the transformer comprises:

a first winding coupled to the first and second terminals; and

a second winding; and

wherein the charging circuit further comprises;

a plurality of diodes coupled to the second winding; and

an inductor coupled between the plurality of diodes and the second ESD.

9. The propulsion system of claim 8 wherein the plurality of diodes comprises a full-wave diode bridge.

10. The propulsion system of claim 8 wherein the transformer further comprises a winding tap coupled to the second winding;

and

wherein the second ESD is further coupled to the winding tap.

11. The propulsion system of claim 1 further comprising a third pair of power switches comprising a fifth power switch coupled in series with a sixth power switch via a third node.

12. A method of assembling a control system comprising:

coupling a first energy storage device (ESD) to a first bi-directional DC-DC converter, the first bi-directional DC-DC converter comprising;

a first pair of power switches coupled in series; and

an inductor coupled to a first node formed between the first pair of power switches;

coupling the first ESD to a second bi-directional DC-DC converter, the second bi-directional DC-DC converter comprising;

a second pair of power switches coupled in series; and

an inductor coupled to a second node formed between the second pair of power switches;

coupling the first and second bi-directional DC-DC converters to a DC link;

coupling the DC link to a motor drive;

coupling a transformer of a charge circuit to the first and second nodes;

coupling a second ESD to the charge circuit to receive a charge voltage therefrom; and

coupling a controller to the first and second bi-directional DC-DC converters and configuring the controller to interleave control of the first and second bi-directional DC-DC converters to cause a variable voltage difference between the first and second nodes during an interleave portion of a frequency period to generate the charge voltage, wherein the second ESD can be charged during operation of the motor drive.

13. The method of claim 12 further comprising configuring the controller to:

increase the interleave portion of the frequency period to increase the amount of charge voltage generated; and

decrease the interleave portion of the frequency period to decrease the amount of charge voltage generated.

14. The method of claim 12 wherein coupling the first ESD to the first bi-directional DC-DC converter comprises coupling a first battery having a first voltage rating to the first bi-directional DC-DC converter;

wherein coupling the second ESD to the charge circuit comprises coupling a second battery having a second voltage rating to the charge circuit; and

where the second voltage rating is lower than the first voltage rating.

15. The method of claim 14 further comprising coupling an auxiliary load to the second ESD.

16. An energy storage arrangement for an electrically powered system, the arrangement comprising:

a first bi-directional DC-DC converter comprising;

a first pair of power switches comprising a first power switch coupled in series with a second power switch via a first node; and

a first inductor coupled to the first node;

a first energy storage device coupled to the first inductor;

a DC link comprising;

a first bus coupled to the first bi-directional DC-DC converter; and

a second bus coupled to the first bi-directional DC-DC converter;

a second pair of power switches comprising;

a third power switch coupled to the first bus; and

a fourth power switch coupled to the second bus and coupled in series with the third power switch via a second node;

a second inductor coupled to the first energy storage device;

a transformer having a first winding comprising;

a first terminal coupled to the first node; and

a second terminal coupled to the second node;

a second energy storage device coupled to receive a charge voltage from the transformer;

a controller coupled to the first and second pairs of power switches and configured to cause a voltage difference between the first and second nodes during an interleave portion of a frequency period to generate the charge voltage; and

an inductor switch coupled between the second inductor and the second node, wherein the controller is further configured to;

close the inductor switch; and

control the second pair of power switches to cause the second pair of power switches to boost a voltage of the first energy storage device to the DC link.

17. The energy storage arrangement of claim 16 wherein the first energy storage device comprises a battery having a first voltage rating, and wherein the second energy storage device comprises a battery having a second voltage rating lower than the first energy storage device.

18. The method of claim 16 wherein the controller is further configured to:

open the inductor switch; and

control the first and second pair of power switches as a phase-shifted converter.

19. The energy storage arrangement of claim 17 wherein the controller is further configured to vary the interleave portion based on a desired amount of the charge voltage to be supplied to the second energy storage device.

20. A propulsion system comprising:

a motor drive;

a direct current (DC) link electrically coupled to the motor drive;

a first leg coupled to the DC link and comprising a first power switch coupled in series with a second power switch via a first node;

a first inductor coupled to the first node, wherein the first leg and inductor form a first bi-directional DC-DC voltage converter;

a first energy storage device (ESD) electrically coupled to the first inductor;

a second leg coupled to the DC link and comprising a third power switch coupled in series with a fourth power switch via a second node;

a charging circuit comprising a transformer having a first terminal coupled to the first node and having a second terminal coupled to the second node;

a second ESD coupled to receive charging energy from the transformer; and

a controller coupled to the first and second legs and configured to cause a variable voltage difference between the first and second nodes during an interleave duration of a frequency period to generate the charging energy, wherein the second ESD can be charged during operation of the motor drive.