Systems and methods to optimize outputs of static inverters in variable energy generation environments

• US 8,957,544 B2
• Filed: 06/09/2011
• Issued: 02/17/2015
• Est. Priority Date: 06/09/2010
• Status: Active Grant

• Current Assignee: Tigo Energy, Inc
• Original Assignee: Tigo Energy, Inc
• Inventors: Avrutsky, Mordechay, Kikinis, Dan
• Primary Examiner(s): KAPLAN, HAL IRA
• Application Number:
  US13/157,016
• Publication Number:
  US 20110304204A1
• Time in Patent Office: 1,349 Days
• Field of Search: 307/25
• US Class Current: 307/25
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• 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 3/46 Controlling of the sharing of output between the generators, converters, or transformers
• CPC Class Codes: H02M 1/42 Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
• CPC Class Codes: H02M 7/42 Conversion of dc power input into ac power output without possibility of reversal
• CPC Class Codes: H02M 7/44 by static converters
• CPC Class Codes: H02M 7/48 using discharge tubes with control electrode or semiconductor devices with control electrode
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects

Abstract

A system to collect energy from generation systems such as, for example, wind farms or solar farms with distributed energy-generation equipment. The energy is collected and transmitted to a feed-in site. At the feed-in site, static inverters alone or in combination with pulse width modulation inverters may be used to feed the energy to a power grid. In some other cases, back-to-back static inverters create a high-voltage direct current to feed a transmission line.

Claims

1. An energy generation system comprising:

a static inverter to provide an alternating current power to a feeding point; and

a pulse width modulation inverter connected in parallel with the static inverter to correct a power factor error in the alternating current power provided by the static inverter.

2. The system of claim 1, further comprising a controller in communication with the static inverter and the pulse width modulation inverter wherein the controller coordinates the static inverter and the pulse width modulation inverter to correct a waveform of the alternating current power.

3. The system of claim 1, further comprising a controller in communication with the feeding point to coordinate the alternating current power with a grid.

4. The system of claim 1, wherein the static inverter inverts a direct current power to a three-phase form of the alternating current power.

5. The system of claim 1, further comprising a bus to supply a direct current power to the static inverter and the pulse width modulation inverter.

6. The system of claim 5, further comprising:

a plurality of variable energy collecting units to produce respective direct current power outputs; and

a plurality of string converters to receive the respective outputs;

wherein the string converters supply the respective outputs to the bus in the form of the direct current power.

7. The system of claim 6, wherein the units are selected from the group consisting of one or more of solar panels, solar poles, and wind power collectors, or any combination thereof.

8. The system of claim 5, further comprising:

one or more variable energy collecting units to produce respective direct current power outputs;

one or more respective string converters to receive the respective outputs; and

a controller in communication with the string converters to enable a conversion of the respective outputs to compatible outputs that are compatible with each other on the bus;

wherein the string converters supply the compatible outputs to the bus in the form of the direct current power.

9. The system of claim 8, wherein the units are selected from the group consisting of solar panels, solar poles, wind power collectors, and any combination thereof.

10. The system of claim 5, further comprising a capacitor in electrical communication with the bus.

11. The system of claim 10, wherein the capacitor is a rotary capacitor.

12. A method for converting energy comprising:

providing, via a static inverter, an alternating current power to a feeding point; and

correcting, via a pulse width modulation inverter connected in parallel with the static inverter, a power factor error in the alternating current power provided by the static inverter.

13. The method of claim 12, further comprising coordinating, via a controller in communication with the static inverter and pulse width modulation inverter, the static inverter and the pulse width modulation inverter, to correct a waveform of the alternating current power.

14. The method of claim 12, further comprising coordinating the alternating current power with a grid via a controller in communication with the feeding point.

15. The method of claim 12, wherein the static inverter inverts a direct current power to a three-phase form of the alternating current power.

16. The method of claim 12, further comprising supplying a direct current power to the static inverter and the pulse width modulation inverter via a bus.

17. The method of claim 16, further comprising:

producing via one or more variable energy collecting units respective direct current power outputs; and

receiving via one or more respective string converters the respective outputs;

wherein the string converters supply the respective outputs to the bus in the form of the direct current power.

18. The method of claim 16, further comprising:

producing via one or more variable energy collecting units respective direct current power outputs;

receiving via one or more respective string converters the respective outputs; and

instructing, via a controller in communication with the string converters, the one or more respective string converters to convert the respective outputs to compatible outputs that are compatible with each other on the bus.

19. The method of claim 16, further comprising a capacitor in electrical communication with the bus.

20. The method of claim 19, wherein the capacitor is a rotary capacitor.