DC power-generation system and integral control apparatus therefor

• US 20070107767A1
• Filed: 11/16/2005
• Published: 05/17/2007
• Est. Priority Date: 11/16/2005
• Status: Abandoned Application

• Current Assignee: Arizona Public Service Company (Pinnacle West Capital Corporation)
• Original Assignee: Arizona Public Service Company (Pinnacle West Capital Corporation)
• Inventors: Schlanger, William, Hayden, Herbert
• Application Number:
  US11/281,970
• Publication Number:
  US 20070107767A1
• Time in Patent Office: Days
• US Class Current: 136/244
• CPC Class Codes: H02J 1/10 Parallel operation of dc sources
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: H02S 50/00 Monitoring or testing of PV systems, e.g. load balancing or fault identification
• CPC Class Codes: H02S 50/10 Testing of PV devices, e.g. of PV modules or single PV cells testing of semiconductor devices during manufacturing H01L22/00
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y02P 90/50 Energy storage in industry with an added climate change mitigation effect

Abstract

A DC power-generation array system (30) is made up of an array (32) of power-generation cells (36) arranged as N strings (38) of M cells (36) each. The system (30) incorporates an integral control apparatus (34) having N string units (52) and a single process unit (54). Each string unit (52) is coupled to one of the strings (38), and is made up of monitor module (72) to measure a string current (I_S(X)) through that string (38), and a switching module (74) to switch that string (38) into and out of the array (32). The process unit (54) is made up of a processor (90) to evaluate the string currents (I_S(X), and a data I/O module (98) to provide a remote monitoring and control of the system (30). The system (30) also has an interface unit (92) to provide local monitoring and control of the system (30). The processor (90) causes the switching modules (74) to couple or decouple strings (38) from array (32) under automatic, remote, and/or local control.

Claims

1. A direct-current (DC) power-generation array system comprising:

a DC power-generation array comprising N strings comprising M DC power-generation cells each, where N is an integer greater than 1, and where M is a positive integer; and

an integral control apparatus having a common substrate and comprising;

a current summing bus affixed to said common substrate and coupled to each of said N strings;

N string units affixed to said common substrate, wherein each of said N string units is coupled between one of said N strings and said current summing bus, and configured to measure a string current through said one string; and

a process unit affixed to said common substrate, coupled to each of said N string units, and configured to evaluate said string current through said one string.

2. A system as claimed in claim 1 wherein said process unit is configured to control electrical connection of said one string to said array.

3. A system as claimed in claim 1 wherein:

said integral control apparatus additionally comprises an interface unit affixed to said common substrate and coupled to said process unit; and

said process unit is configured to control connection of said one string in response to an instruction from said interface unit.

4. A system as claimed in claim 1 wherein:

each of said N string units is configured to effect electrical connection of said one string to said current summing bus; and

said process unit is configured to control electrical connection of said one string by said string unit.

5. A system as claimed in claim 4 wherein each of said N string units comprises:

a monitor module coupled to said one string and configured to measure said string current through said one string; and

a switching module coupled between said monitor module and said current summing bus and configured to effect electrical connection of said one string and said current summing bus.

6. A system as claimed in claim 5 wherein said switching module is configured to effect electrical connection of said one string with one of said current summing bus and a dynamic load.

7. A system as claimed in claim 5 wherein said process unit comprises a processor coupled to said monitor module and switching module, configured to evaluate said string current measured by said monitor module, and configured to control connection of said one string by said switching module.

8. A system as claimed in claim 5 wherein said process unit comprises:

a data input/output (I/O) module in communication with a remote location; and

a processor coupled to said data I/O module, coupled to said switching module, and configured to control connection of said one string by said switching module in response to instructions from said remote location.

9. A system as claimed in claim 1 wherein:

said current summing bus is a first current summing bus configured to produce an output of said array of a first polarity; and

said integral control apparatus additionally comprises a second current summing bus coupled to said N strings and configured to produce an output of said array of a second polarity.

10. A system as claimed in claim 9 wherein said N string units are coupled to said first current summing bus and said second current summing bus.

11. A system as claimed in claim 9 wherein:

said each string unit is configured to effect an electrical connection of said one string to one of said first current summing bus and a dynamic load.

12. A system as claimed in claim 11 wherein:

said dynamic load is a common dynamic load; and

each of a plurality of said N string units is configured to connect one of said strings to said common dynamic load.

13. A system as claimed in claim 11 wherein said integral control apparatus is configured to measure a string voltage of said one string when said one string is coupled to said dynamic load.

14. A system as claimed in claim 1 wherein, for each of said N strings, said system additionally comprises:

a first interconnect coupled between a first output of each of said N strings and a first input of said integral control apparatus; and

a second interconnect coupled between a second output of each of said N string units and a second input of said integral control apparatus.

15. An integral control apparatus for a direct-current (DC) power-generation array formed of N strings, where N is an integer greater than 1, said apparatus comprising:

a common substrate;

a string unit affixed to said common substrate, coupled to one of said N strings, and configured to measure a string current through said one string; and

a process unit affixed to said common substrate, coupled to said string unit, and configured to evaluate said string current though said one string.

16. An apparatus as claimed in claim 15 wherein said common substrate comprises:

a non-conductive base substrate; and

a multiplicity of conductive traces formed upon said non-conductive base substrate, wherein said conductive traces serve to connect components of said string units and said process unit affixed to said common substrate.

17. An apparatus as claimed in claim 16 wherein:

said string unit is configured to electrically switch said one string into and out of said array; and

said process unit is configured to cause said string unit to electrically switch said one string into and out of said array.

18. An apparatus as claimed in claim 17 wherein said process unit is configured to evaluate said string current and to cause said string unit to electrically switch said one string into and out of said array in response to said string current.

19. An apparatus as claimed in claim 18 wherein:

said process unit is configured to switch said one string into said array when said string current is evaluated to be within a predetermined current range; and

said process unit is configured to switch said one string out of said array when said string current is evaluated to be outside of said predetermined current range.

20. An apparatus as claimed in claim 15 wherein said string unit comprises:

a monitor module coupled to said one string and configured to measure said string current through said one string; and

a switching module coupled to said monitor module and configured to electrically switch said one string into and out of said array.

21. An apparatus as claimed in claim 20 wherein said process unit comprises a processor coupled to said monitor module, coupled to said switching module, configured to evaluate said string current, and configured to cause said switching module to switch said one string out of said array upon one of said string current is evaluated to be outside of a predetermined current range and upon operator command.

22. An apparatus as claimed in claim 21 wherein said process unit additionally comprises an analog to digital converter coupled between said monitor module and said processor and configured to digitize a value of said string current.

23. An apparatus as claimed in claim 15 wherein said string unit is one of N substantially identical string units, and wherein each of said N string units is coupled to one of said N strings, coupled to said process unit, and coupled to a current summing bus configured to electrically sum said string current through each of said N strings to produce an array current.

24. A direct-current (DC) power-generation array system comprising:

a DC power-generation array comprising N×

M DC power-generation cells arranged as N strings of M cells each, where N is an integer greater than 1, and where M is a positive integer;

an integral control apparatus comprising;

a common substrate;

N string units affixed to said common substrate, wherein each of said N string units is coupled to one of said N strings and comprises;

a monitor module configured to measure a string current through said one string; and

a switching module configured to effect electrical couple and decouple said one string with a remainder of said N strings;

a current summing bus affixed to said common substrate, coupled to each of said N string units, and configured to sum said string currents from each of said N strings;

a process unit comprising;

a processor coupled to each of said monitor modules, coupled to each of said switching modules, configured to evaluate each of said string currents through said N strings, and configured to cause said switching modules to couple and decouple said strings with said array; and

a data input/output module configured to provide a remote control of said processor; and

an interface unit affixed to said common substrate, coupled to said process unit, and configured to provide local control of said processor, wherein said processor is configured to cause each of said switching modules to one of couple and decoupled an associated one of said strings with said array in response to one of an automatic control, said remote control, and said local control