ARCHITECTURE FOR POWER PLANT COMPRISING CLUSTERS OF POWER-GENERATION DEVICES

• US 20140319916A1
• Filed: 07/08/2014
• Published: 10/30/2014
• Est. Priority Date: 08/22/2007
• Status: Active Grant

• Current Assignee: Maxout Renewables, Inc.
• Original Assignee: Maxout Renewables, Inc.
• Inventors: Cummings, Eric Bryant
• Granted Patent: US 9,407,093 B2
• Time in Patent Office: Days
• US Class Current: 307/53
• CPC Class Codes: H01L 31/02021 for solar cells electrical connection means, e.g. junction boxes, specially adapted for structural association with photovoltaic modules H02S40/34
• CPC Class Codes: H02J 1/001 Hot plugging or unplugging of load or power modules to or from power distribution networks
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 1/106 for load balancing, symmetrisation, or sharing
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 9/062 for AC powered loads
• CPC Class Codes: H02M 1/0043 Converters switched with a phase shift, i.e. interleaved non-isolated DC/DC converters H02M3/1586
• CPC Class Codes: H02M 7/493 the static converters being arranged for operation in parallel
• CPC Class Codes: H02S 40/32 comprising DC/AC inverter means associated with the PV module itself, e.g. AC modules
• CPC Class Codes: Y02B 10/70 Hybrid systems, e.g. uninterruptible or back-up power supplies integrating renewable energies
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

Various techniques are employed alone or in combination, to reduce the levelized cost of energy imposed by a power plant system. Solar energy concentrators in the form of inflated reflectors, focus light onto photovoltaic receivers. Multiple concentrators are grouped into a series-connected cluster that shares control circuitry and support structure. Individual concentrators are maintained at their maximum power point via balance controllers that control the flow of current that shunts this series connection. DC current from clusters is transmitted moderate distances to a centralized inverter. The inductance of transmission lines is maximized using an air-spaced twisted pair, enhancing the performance of boost-type three phase inverters. Cluster outputs are separate from individual inverters in massively interleaved arrays co-located at a central location. Step-up transformers convert inverter voltages to grid voltages, and small transformers provide isolation and voltage step-up only on receiver-to-receiver imbalance currents, typically <20% of the total current.

Claims

1. A method for balancing circuit voltage comprising:

receiving, at a circuit, power from a plurality of power-generating elements, the circuit being coupled to first and second devices, the first device being communicatively coupled to the second device; and

increasing, using a switch of the second device, a load on at least one of the plurality of power-generating elements such that the voltage of the circuit does not exceed an upper threshold voltage.

2. The method of claim 1, wherein the first device is an inverter and the second device is a balancer.

3. The method of claim 1, wherein the switch is a semiconductor or mechanical relay.

4. The method of claim 1, wherein the circuit includes a pair of wires that are spaced a first distance apart and are helically twisted.

5. The method of claim 4, wherein the circuit further includes an insulator disposed between the pair of wires.

6. The method of claim 4, wherein the first distance is greater than a diameter of each of the pair of wires.

7. The method of claim 6, wherein the helically twisted pair of wires is flattened.

8. A method for balancing circuit voltage comprising:

receiving, at a circuit, power from a plurality of power-generating elements, the circuit being coupled to first and second devices, the first device being communicatively coupled to the second device; and

boosting, using a switch and an inductor of the second device, the voltage produced by at least one of the plurality of power-generating elements such that the voltage of the circuit does not fall below a lower threshold voltage.

9. The method of claim 8, wherein the first device is an inverter and the second device is a balancer.

10. A method for calibrating a circuit comprising:

receiving, at the circuit, power from a plurality of power-generating elements, the circuit being coupled to first and second devices, the first device being communicatively coupled to the second device;

determining, using a current calibrator of the first device, a first current calibration measurement; and

determining, by the second device and using the determined first current calibration measurement, a second current calibration measurement.

11. The method of claim 10, further comprising:

determining, using a voltage calibrator of a third device, a first voltage calibration measurement, wherein the third device is coupled to the circuit; and

determining, by a fourth device and using the determined first voltage calibration measurement, a second voltage calibration measurement, wherein the fourth device is coupled to the circuit, wherein the third and fourth devices are communicatively coupled.

12. The method of claim 10, wherein the first device is an inverter and the second device is a balancer.

13. The method of claim 10, further comprising:

determining, by a tertiary device and using the determined second current calibration measurement, a third current calibration measurement.

14. The method of claim 13, wherein the second device is a balancer and the tertiary device is a balancer channel.

15. A method for calibrating a master inverter comprising:

calibrating each of a plurality of communicatively coupled individual inverters using a first current calibration measurement, wherein each of the plurality of individual inverters are coupled to an analog circuit; and

determining, by each of the individual inverters, a second current calibration measurement using the first current calibration measurement.

16. The method of claim 15, further comprising:

calibrating each of the plurality of communicatively coupled individual inverters using a first voltage calibration measurement; and

determining, by each of the individual inverters, a second voltage current calibration measurement using the first voltage current calibration measurement.