SYSTEM AND METHOD FOR CONTROLLING SWITCHING ELEMENTS WITHIN A SINGLE-PHASE BRIDGE CIRCUIT

• US 20150084337A1
• Filed: 09/25/2013
• Published: 03/26/2015
• Est. Priority Date: 09/25/2013
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: Wagoner, Robert Gregory, Klodowski, Anthony Michael, Greenleaf, Todd David
• Granted Patent: US 9,362,859 B2
• Time in Patent Office: Days
• US Class Current: 290/44
• CPC Class Codes: H02M 1/38 Means for preventing simultaneous conduction of switches
• CPC Class Codes: H02M 1/385 with means for correcting output voltage deviations introduced by the dead time
• CPC Class Codes: H02M 5/4585 having a rectifier with controlled elements
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• CPC Class Codes: H02P 2101/15 for wind-driven turbines
• CPC Class Codes: H02P 9/007 Control circuits for doubly fed generators

Abstract

In one aspect, a method for controlling the operation of switching elements contained within a single-phase bridge circuit of a power convertor may include monitoring gate voltages of a first switching element and a second switching element of the single-phase bridge circuit and controlling the first and second switching elements so that each switching element is alternated between an activated state and a deactivated state. In addition, the method may include transmitting a gating command signal to adjust the first switching element from the deactivated state to the activated state when: a first gate drive command is received that is associated with switching the first switching element to the activated state; a second gate drive command is received that is associated with switching the second switching element to the deactivated state; and the gate voltage of the second switching element is less than a predetermined voltage threshold.

Claims

1. A method for controlling the operation of switching elements contained within a single-phase bridge circuit of a power convertor, the method comprising:

monitoring, with a computing device, gate voltages of a first switching element and a second switching element of the single-phase bridge circuit;

controlling the first and second switching elements so that each switching element is alternated between an activated state and a deactivated state; and

transmitting a gating command signal to adjust the first switching element from the deactivated state to the activated state when;

a first gate drive command is received that is associated with switching the first switching element to the activated state;

a second gate drive command is received that is associated with switching the second switching element to the deactivated state; and

the gate voltage of the second switching element is less than a predetermined voltage threshold.

2. The method of claim 1, further comprising transmitting a second gating command signal to adjust the first switching element from the activated state to the deactivated state.

3. The method of claim 4, further comprising transmitting a third gating command signal to adjust the second switching element from the deactivated state to the activated state when:

a third gate drive command is received that is associated with switching the second switching element to the activated state;

a fourth gate drive command is received that is associated with switching the first switching element to the deactivated state; and

the gate voltage of the first switching element is less than a predetermined voltage threshold.

4. The method of claim 1, wherein the first and second switching elements comprise insulated gate bipolar transistors.

5. The method of claim 1, wherein the predetermined voltage threshold corresponds to a gate turn-on voltage for the first and second switching elements.

6. The method of claim 1, further comprising determining whether current is flowing into the first switching element or a first diode associated with the first switching element.

7. The method of claim 6, wherein the gating command signal is transmitted to adjust the first switching element from the deactivated state to the activated state when:

the first gate drive command is received;

the second gate drive command is received;

the gate voltage of the second switching element is less than a predetermined voltage threshold; and

it is determined that current is flowing into the first switching element.

8. A method for controlling the operation of switching elements contained within a single-phase bridge circuit of a power convertor, the method comprising:

controlling, with a computing device, operation of a first switching element and a second switching element of the single-phase bridge circuit so that each switching element is alternated between an activated state and a deactivated state;

determining whether current is flowing into the first switching element or a first diode associated with the first switching element; and

maintaining the first switching element in the deactivated state when it is determined that current is flowing into the first diode.

9. The method of claim 8, further comprising monitoring a collector-emitter voltage of the first switching element to determine whether current is flowing into the first switching element or the first diode.

10. The method of claim 8, further comprising monitoring a current direction through the first switching element to determine whether current is flowing into the first switching element or the first diode.

11. The method of claim 8, further comprising switching the first switching element to the activated state when it is determined that current is flowing into the first switching element.

12. The method of claim 8, further comprising:

determining whether current is flowing into the second switching element or a second diode associated with the second switching element; and

maintaining the second switching element in the deactivated state when it is determined that current is flowing into the second diode.

13. The method of claim 12, further comprising switching the second switching element to the activated state when it is determined that current is flowing into the second switching element.

14. The method of claim 8, wherein the first and second switching elements comprise insulated gate bipolar transistors.

15. The method of claim 8, further comprising monitoring gate voltages of the first and second switching elements.

16. The method of claim 15, further comprising switching the first switching element to the activated state when:

a first gate drive command is received that is associated with switching the first switching element to the activated state;

a second gate drive command is received that is associated with switching the second switching element to the deactivated state;

the gate voltage of the second switching element is less than a predetermined voltage threshold; and

it is determined that current is flowing into the first switching element.

17. A wind turbine system for supplying power for application to a load, the wind turbine system comprising:

a wind turbine rotor, the wind turbine rotor including a hub and a plurality of rotor blades coupled to the hub;

a generator coupled to the wind turbine rotor;

a power converter coupled to the generator, the power converter including a single-phase bridge circuit having a first switching element and a second switching element; and

a controller communicatively coupled to the power convertor, the controller being configured to;

monitor gate voltages of the first and second switching elements;

control the first and second switching elements so that each switching element is alternated between an activated state and a deactivated state; and

transmit a gating command signal to adjust the first switching element from the deactivated state to the activated state when;

a first gate drive command is received that is associated with switching the first switching element to the activated state;

a second gate drive command is received that is associated with switching the second switching element to the deactivated state; and

the gate voltage of the second switching element is less than a predetermined voltage threshold.

18. The system of claim 17, wherein the generator is a doubly-fed induction generator.

19. The system of claim 17, wherein the controller is further configured to determine whether current is flowing into the first switching element or a first diode associated with the first switching element.

20. The system of claim 17, wherein the controller is configured to transmit the gating command signal to adjust the first switching element from the deactivated state to the activated state when:

the first gate drive command is received;

the second gate drive command is received;

the gate voltage of the second switching element is less than a predetermined voltage threshold; and

it is determined that current is flowing into the first switching element.