Method and system for providing central control in an energy generating system

• US 7,962,249 B1
• Filed: 05/14/2008
• Issued: 06/14/2011
• Est. Priority Date: 05/14/2008
• Status: Active Grant

• Current Assignee: National Semiconductor Corporation (Texas Instruments, Inc.)
• Original Assignee: National Semiconductor Corporation (Texas Instruments, Inc.)
• Inventors: Lisi, Gianpaolo, Djabbari, Ali, Zhang, Jianhui
• Primary Examiner(s): Masinick; Michael D
• Application Number:
  US12/152,479
• Time in Patent Office: 1,126 Days
• Field of Search: 700/295, 700/297, 307/82
• US Class Current: 700/295
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• 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 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers

Abstract

A central array controller for an energy generating array is provided. The array includes a plurality of energy generating devices, and each energy generating device is coupled to a corresponding local converter. The central array controller includes a diagnostic module that is capable of receiving, from each local converter in the array, device data for the energy generating device corresponding to the local converter. In one embodiment, the diagnostic module is also capable of receiving, from each local converter in the array, local converter data for the local converter.

Claims

1. A central array controller for an energy generating array that comprises a plurality of energy generating devices in a system, each energy generating device coupled to a corresponding local converter, the central array controller comprising:

a diagnostic module configured to receive data from each local converter in the array, the data comprising at least one of;

device data for the energy generating device corresponding to the local converter and local converter data for the local converter; and

a control module configured to send a control signal to each of the local converters based on the data in order to prompt at least one of the local converters to take at least one action identified by the control signal;

wherein;

each local converter comprises a local controller configured to determine a maximum power point for its corresponding energy generating device;

the system is configured to operate in a distributed mode and a centralized mode; and

the control signal comprises at least one of;

a correction signal that corrects at least one of the maximum power points determined by at least one of the local controllers when the system is in the distributed mode, an enable signal that enables the local controllers in the distributed mode, and a disable signal that disables the local controllers in the centralized mode.

2. The central array controller of claim 1, wherein:

the diagnostic module is further configured to analyze the data to generate analysis results; and

the control signal is based on the analysis results.

3. The central array controller of claim 2, wherein the analysis results comprise statistics for each energy generating device that are based on at least one specified period of time.

4. The central array controller of claim 1, wherein the diagnostic module is further configured to provide fault monitoring for the array by identifying defective energy generating devices in the array based on the data.

5. The central array controller of claim 1, wherein the data comprises maximum power point tracking (MPPT) information for each of the energy generating devices.

6. The central array controller of claim 1, wherein the control module is further configured to receive instructions from an operator and to send the control signal to the at least one local converter based on the received instructions.

7. The central array controller of claim 1, wherein the control module is further configured to:

calibrate the maximum power point for each energy generating device based on the data; and

based on the calibrated maximum power points, send a conversion ratio command to each local converter to cause the energy generating device corresponding to the local converter to operate at the maximum power point for the energy generating device, the control signal comprising the conversion ratio commands.

8. The central array controller of claim 1, wherein the energy generating devices comprising comprise photovoltaic panels.

9. An energy generating system comprising:

an energy generating array that comprises a plurality of energy generating devices, each energy generating device coupled to a corresponding local converter; and

a central array controller comprising;

a diagnostic module configured to receive data from each local converter in the array, the data comprising at least one of;

(i) device data for the energy generating device corresponding to the local converter and (ii) local converter data for the local converter; and

a control module configured to send a control signal to each of the local converters based on the data in order to prompt at least one of the local converters to take at least one action identified by the control signal;

wherein;

each local converter comprises a local controller configured to determine a maximum power point for its corresponding energy generating device;

the system is configured to operate in a distributed mode and a centralized mode; and

the control signal comprises at least one of;

a correction signal that corrects at least one of the maximum power points determined by at least one of the local controllers when the system is in the distributed mode, an enable signal that enables the local controllers in the distributed mode, and a disable signal that disables the local controllers in the centralized mode.

10. The energy generating system of claim 9, wherein:

the diagnostic module is further configured to analyze the device data and the local converter data to generate analysis results, and

the analysis results comprise statistics for each energy generating device that are based on at least one specified period of time.

11. The energy generating system of claim 9, wherein the diagnostic module is further configured to provide fault monitoring for the array by identifying defective energy generating devices in the array based on the data.

12. The energy generating system of claim 9, wherein the data comprises maximum power point tracking (MPPT) information for each of the energy generating devices.

13. The energy generating system of claim 9, wherein the control module is further configured to receive instructions from an operator and to send the control signal to the at least one local converter based on the received instructions.

14. The energy generating system of claim 9, wherein the control module is further configured to:

calibrate the maximum power point for each energy generating device based on the data; and

based on the calibrated maximum power points, send a conversion ratio command to each local converter to cause the energy generating device corresponding to the local converter to operate at the maximum power point for the energy generating device, the control signal comprising the conversion ratio commands.

15. The energy generating system of claim 9, wherein the energy generating devices comprise photovoltaic panels.

16. A method for providing central control in an energy generating system that comprises an energy generating array, the array comprising a plurality of energy generating devices, each energy generating device coupled to a corresponding local converter, the method comprising:

receiving data from each local converter in the array, the data comprising at least one of;

(i) device data for the energy generating device corresponding to the local converter and (ii) local converter data for the local converter; and

sending a control signal to each of the local converters based on the data in order to prompt at least one of the local converters to take at least one action identified by the control signal;

wherein;

each local converter comprises a local controller configured to determine a maximum power point for its corresponding energy generating device;

the system is configured to operate in a distributed mode and a centralized mode; and

the control signal comprises at least one of;

a correction signal that corrects at least one of the maximum power points determined by at least one of the local controllers when the system is in the distributed mode, an enable signal that enables the local controllers in the distributed mode, and a disable signal that disables the local controllers in the centralized mode.

17. The method of claim 16, further comprising analyzing the data to generate analysis results, wherein the control signal is based on the analysis results.

18. The method of claim 17, further comprising:

identifying defective energy generating devices in the array based on the analysis results.

19. The method of claim 16, further comprising:

calibrating the maximum power point for each energy generating device based on the data; and

based on the calibrated maximum power points, sending a conversion ratio command to each local converter to cause the energy generating device corresponding to the local converter to operate at the maximum power point for the energy generating device, the control signal comprising the conversion ratio commands.

20. The method of claim 16, wherein the energy generating devices comprise photovoltaic panels.