SYSTEMS AND METHODS FOR SOLAR PHOTOVOLTAIC ENERGY COLLECTION AND CONVERSION

• US 20130181527A1
• Filed: 07/11/2012
• Published: 07/18/2013
• Est. Priority Date: 07/11/2011
• Status: Active Grant

• Current Assignee: SineWatts, Inc.
• Original Assignee: SineWatts, Inc.
• Inventors: Bhowmik, Shibashis
• Granted Patent: US 9,531,293 B2
• Time in Patent Office: Days
• US Class Current: 307/63
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/40 Synchronising a generator for connection to a network or to another generator
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: H02M 3/33584 Bidirectional converters
• CPC Class Codes: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H02M 7/44 by static converters
• CPC Class Codes: H02M 7/49 Combination of the output voltage waveforms of a plurality of converters
• 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

Abstract

A circuit for an energy collection system is provided that includes one or more strings that are configured to couple to an electrical load. Each of the one or more strings comprises one or more string members that are coupled to each other in series. Each of the one or more string members comprises (i) a connection to receive an output from an energy output device, and (ii) an inverter configured to convert the output of the energy output device into alternating current (AC) energy. The circuit includes a controller that controls the output that is provided by the one or more strings by controlling the individual string member.

Claims

1. A circuit for an energy collection system comprising:

one or more strings to couple to an electrical load, each of the one or more strings comprising one or more string members coupled to each other in series, wherein each of the one or more string members comprises (i) a connection to receive an output from an energy output device, and (ii) an inverter configured to convert the output of the energy output device into alternating current (AC) energy; and

a controller that controls an output that is provided by the one or more strings by controlling the one or more string members.

2. The circuit of claim 1, wherein each of the one or more string members further comprises a control circuit to receive one or more commands from the controller.

3. The circuit of claim 1, wherein the controller controls the output by controlling at least one of a string member output voltage, a string member output current, or a string member output power of each of the one or more string members.

4. The circuit of claim 1, wherein the electrical load further comprises a grid interface to couple the energy collection system to an electrical grid.

5. The circuit of claim 4, wherein the electrical load further comprises one or more grid disconnect switches that is controlled by the controller, and wherein the controller is configured to cause the one or more grid disconnect switches to change states during faulty conditions.

6. The circuit of claim 4, wherein the AC energy that is converted by the inverter of each of the one or more string members has at least one of (i) an AC voltage output whose magnitude is based on at least one of a voltage or current magnitude or a power or energy sourcing and sinking capability of an input energy source or storage of the respective string member, (ii) a phase output that is based on a phase of the electrical grid, or (iii) a frequency output that is based on a frequency of the electrical grid.

7. The circuit of claim 4, wherein each of the one or more string members further comprises a power balancing circuit configured to balance the output provided by an energy output device with the AC energy that is to be delivered to the electrical grid.

8. The circuit of claim 1, wherein each of the one or more string members further comprises a current equalizing circuit configured to control an amount of current a respective string member is to output.

9. The circuit of claim 1, wherein the controller includes at least one of a current equalizing circuit configured to control an amount of current each of the one or more string members is to output, or a voltage compensating circuit configured to control an amount of voltage each of the one or more string members is to output.

10. The circuit of claim 1, wherein the energy output device includes a photovoltaic (PV) panel or other energy collection or generation device.

11. An energy collection system comprising:

an electrical load;

one or more strings connected to the electrical load, each of the one or more strings comprising one or more string members coupled to each other in series, wherein each of the one or more string members comprises (i) a connection to receive an output from an energy output device, and (ii) an inverter configured to convert the output of the energy output device into alternating current (AC) energy; and

a controller that controls an output that is provided by the one or more strings by controlling the one or more string members.

12. The energy collection system of claim 11, wherein each of the one or more string members further comprises a control circuit configured to receive one or more commands from the controller to control a respective string member.

13. The energy collection system of claim 11, wherein each of the one or more string members further comprises a DC to DC converter configured to boost or buck the DC energy provided by the energy output device.

14. The energy collection system of claim 11, wherein the electrical load further comprises a grid interface to couple the energy collection system to an electrical grid.

15. The energy collection system of claim 14, wherein the electrical load further comprises one or more grid disconnect switches that is controlled by the controller, the controller causing the one or more grid disconnect switches to change states during faulty conditions.

16. The energy collection system of claim 14, wherein the AC energy that is converted by the inverter of each of the one or more string members has at least one of (i) an AC voltage output whose magnitude is based on at least one of a voltage or current magnitude or a power or energy sourcing and sinking capability of an input energy source or storage of the respective string member, (ii) a phase output that is based on a phase of the electrical grid, or (iii) a frequency output that is based on a frequency of the electrical grid.

17. The energy collection system of claim 14, wherein each of the one or more string members further comprises a power balancing circuit configured to balance the output provided by an energy output device with the AC energy that is to be delivered to the electrical grid.

18. The energy collection system of claim 11, wherein each of the one or more string members further comprises a current equalizing circuit configured to control an amount of current a respective string member is to output.

19. The energy collection system of claim 11, wherein the controller includes at least one of a current equalizing circuit configured to control an amount of current each of the one or more string members is to output, or a voltage compensating circuit configured to control an amount of voltage each of the one or more string members is to output.

20. The energy collection system of claim 11, wherein the energy output device includes a photovoltaic (PV) panel or other energy collection or generation device.