Low cost current source converters for power generation application

• US 8,698,335 B2
• Filed: 06/21/2010
• Issued: 04/15/2014
• Est. Priority Date: 06/21/2010
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Dai, Jingya, Zargari, Navid R., Wu, Bin, Xu, David Dewei, Wang, Jiacheng
• Primary Examiner(s): GONZALEZ, JULIO CESAR
• Application Number:
  US12/819,878
• Publication Number:
  US 20110310642A1
• Time in Patent Office: 1,394 Days
• Field of Search: 290/44, 290/55, 322/44, 322/89
• US Class Current: 290/44
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/48 Controlling the sharing of the in-phase component
• CPC Class Codes: H02J 3/50 Controlling the sharing of the out-of-phase component
• CPC Class Codes: H02M 1/126 using passive filters
• CPC Class Codes: H02M 5/458 using semiconductor devices only
• CPC Class Codes: H02M 7/06 using discharge tubes without control electrode or semiconductor devices without control electrode
• CPC Class Codes: H02M 7/1626 with automatic control of the output voltage or current
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects

Abstract

A system comprising low cost topology for power converter systems is provided. The system takes advantage of the voltage-boost characteristic of a current source inverter (CSI) and utilizes a PWM CSI as a grid-side converter for power generation systems. Moreover, the generator-side converter employs low-cost devices, such as, but not limited to diode bridge, thyristor bridge, and/or a combination of diodes and thyristors, and accordingly simplifies generator-side converter and control. Further, the system provides a wider range of operation than traditional voltage source converter based topologies that utilize a voltage source inverter (VSI) as the grid-side convertor along with a diode rectifier as the generator-side converter.

Claims

1. A system, comprising:

a first generator-side converter circuit comprising a first diode bridge and coupled in series with a second generator-side converter circuit comprising a second diode bridge,

wherein the first generator-side converter circuit is coupled to a first generator of a set of generators that is coupled to a turbine and the second generator-side converter circuit is coupled to a second generator of the set of generators, the first generator and the second generator convert kinetic energy generated by the turbine to an electrical energy signal, and the first generator-side converter circuit and the second generator-side converter circuit receive the electrical energy signal and output a direct current signal based on the electrical energy signal; and

a grid-side converter circuit, coupled to outputs of the first generator-side converter circuit and the second generator-side converter circuit via a direct current link, comprising a current source inverter circuit that converts the direct current signal to a three-phase alternating current signal, wherein a direct current link voltage is varied to control the first generator-side converter circuit and the second generator-side converter circuit to facilitate an increase in power received from the set of generators.

2. The system of claim 1, wherein the current source inverter circuit comprises a thyristor bridge that receives a gating current signal that controls a thyristor of the thyristor bridge.

3. The system of claim 1, wherein the current source inverter is a pulse width modulated current source inverter.

4. The system of claim 1, wherein, the direct current link comprises an inductor.

5. The system of claim 1, wherein, the direct current link comprises a cable that is determined to satisfy a length criterion.

6. The system of claim 1, wherein the first generator of the set of generators is an electrical excited synchronous generator.

7. The system of claim 1, wherein the first generator of the set of generators is a permanent magnet synchronous generator.

8. The system of claim 1, wherein the three-phase alternating current signal is directed to a utility grid circuit.

9. The system of claim 8, further comprising:

a three phase capacitor coupled to an output of the grid-side converter circuit that facilitates filtering a harmonic frequency prior to directing the three-phase alternating current signal to the utility grid.

10. The system of claim 1, wherein the turbine comprises a hydro turbine.

11. The system of claim 1, wherein the direct current signal that passes through the direct current link is adjusted based on control objective information.

12. The system of claim 1, wherein the turbine comprises a wind turbine.

13. The system of claim 1, wherein the first generator-side converter circuit and the second generator-side converter circuit are coupled in series with a third generator-side converter circuit comprising a thyristor bridge, and an output signal from the third generator-side converter circuit is provided to the grid-side converter circuit.

14. A method, comprising:

receiving, by an interconnection circuit, an electrical signal via a set of generators coupled to a turbine that convert kinetic energy generated by the turbine to the electrical signal;

converting, by the interconnection circuit, the electrical signal to a direct current signal by employing a first diode bridge circuit coupled to a first generator of the set of generators and a second diode bridge circuit coupled to a second generator of the set of generators, wherein the first diode bridge circuit and the second diode bridge circuit are coupled in series; and

directing, by the interconnection circuit, the direct current signal to a current source inverter circuit via a direct current link to facilitate a conversion of the direct current signal to a three-phase alternating current signal, wherein a voltage across the direct current link is adjusted to control the first diode bridge circuit and the second diode bridge converter circuit and facilitate an increase in power received from the set of generators.

15. The method of claim 14, wherein the receiving comprises receiving the electrical signal from the set of generator that is coupled to a wind turbine.

16. The method of claim 14, wherein the receiving comprises receiving the electrical signal from the set of generators that is coupled to a hydro turbine.

17. The method of claim 14, wherein the converting comprises converting the electrical signal to the direct current signal by employing a thyristor bridge circuit coupled in series with the first diode bridge circuit and the second diode bridge circuit.

18. The method of claim 14, wherein the directing comprises directing the direct current signal to a pulse width modulated current source inverter circuit.

19. A method, comprising:

converting, by a set of generators, kinetic energy generated by a turbine into an electrical energy signal; and

providing the electrical energy signal to a current source inverter circuit via a first diode bridge circuit and a second diode bridge circuit that are coupled in series to facilitate a generation of a three-phase alternating current signal, wherein the first diode bridge circuit is coupled to a first generator of the set of generators and the second diode bridge circuit is coupled to a second generator of the set of generators and wherein the voltage across a direct current link that couples the first diode bridge circuit and the second diode bridge circuit to the current source inverter circuit is modified to control a power signal provided by the set of generators.

20. The method of claim 19, wherein the converting comprises converting, to the electrical energy signal, the kinetic energy generated by a hydro turbine.