Reconfigurable PV Configuration
A PV module is described with an array of PV cells whereby the module is reconfigurable, allowing different configurations to be applied after installation and during operation, i.e. at run-time. The run time configuration of the module has controllable devices. The main controllable devices are any of (individually or in combination): a) switches which determine the parallel/series connections of the cells as well as hybrid cases also. b) switches between the cells and local dc/dc converters and/or among the DC/DC converters; c) actively controlled bypass diodes placed in order to allow excess current to flow in the occurrence of a mismatch.
1. A photovoltaic module comprising:
an array of a plurality of photovoltaic cells, wherein the photovoltaic cells are arranged in substrings, each substring comprising at least two photovoltaic cells, and the photovoltaic cells within a respective substring are non-divisibly joined in series, and the array has an initial configuration and a run-time configuration, wherein the initial configuration and the run-time configuration are non-uniform;
local DC-DC converters integrated within the photovoltaic module and directly connectable to the sub strings of photovoltaic cells; and
a plurality of switches integrated within the photovoltaic module and located between the substrings and the DC-DC converters, wherein the plurality of switches is selectively controlled to reconfigure the array into the non-uniform run-time configuration by forming direct connections of two or more substrings, wherein the direct connections comprise at least one of (a) a direct parallel connection of the two or more substrings, (b) a direct series connection of the two or more substrings, or (c) a hybrid connection of the two or more sub strings,
wherein the array is responsive to a non-uniform photonic stimulation by a non-uniform re-arrangement of the direct connections of the substrings.
2. The photovoltaic module of claim 1 , wherein the array comprises at least one parallel connection of two or more substrings and at least one series connection of two or more substrings.
3. The photovoltaic module of claim 1 , wherein one or more of the plurality of switches is located between two or more of the DC-DC converters.
4. The photovoltaic module of claim 1 , further comprising one or more actively-controlled bypass diodes arranged to allow excess current to flow in an occurrence of a mismatch of currents between a substring and at least one of the DC-DC converters.
5. The photovoltaic module of claim 4 , wherein the one or more actively-controlled bypass diodes are placed across one of the substrings.
6. The photovoltaic module of claim 4 , wherein the one or more actively-controlled bypass diodes are placed across one or more of the photovoltaic cells included in the plurality of photovoltaic cells.
7. The photovoltaic module of claim 4 , wherein the one or more actively-controlled bypass diodes are placed across one or more of the photovoltaic cells within one of the substrings.
8. The photovoltaic module of claim 4 , wherein the one or more actively-controlled bypass diodes are placed across two or more adjacent substrings.
9. The photovoltaic module of claim 1 , wherein at least one of:
(i) wired connections to DC-DC converters are substantially on one side of the photovoltaic module, or
(ii) one or more connections between up-going substrings and down-going substrings are paired.
10. The photovoltaic module of claim 1 , wherein the connections include one or more hybrid connections, and wherein at least one of:
(i) wired connections do not cross from one side of the photovoltaic module to another side of the photovoltaic module, or
(ii) one of the DC-DC converters is connected to a group of connections that starts with one of one or more hybrid connections, wherein non-uniform stimulation conditions are used to identify a non-uniform subset of substrings.
11. The photovoltaic module of claim 1 , wherein at least one of:
(i) the DC-DC converters are located on one side of the photovoltaic module, or
(ii) each of the DC-DC converters are connected to an even number of substrings.
12. The photovoltaic module of claim 1 , wherein N is a number of the DC-DC converters, M is a number of substrings in the array, and N is less than or equal to M/2, wherein M and N are positive integers.
13. The photovoltaic module of claim 1 , wherein each of the DC-DC converters is connected to a grouping of sub strings, and wherein the DC-DC converters are connected in series by one or more switches.
14. The photovoltaic module of claim 1 , wherein:
if the photovoltaic module is split in a non-uniform vertical split, then the DC-DC converters are placed on one or more sides of the photovoltaic module, and
if the photovoltaic module is not split in the non-uniform vertical split, then the DC-DC converters are placed in a middle of the photovoltaic module between split parts of the photovoltaic module.
15. The photovoltaic module of claim 1 , further comprising one or more bypass diodes, wherein each bypass diodes provides at least one of:
(i) a current bypass across at least one of a grouping of sub strings,
(ii) a current bypass across at least one substring, or
(iii) a connection between two adjacent substrings.
16. The photovoltaic module of claim 1 , wherein:
a number of substrings of the photovoltaic module is N, wherein N is a positive integer,
if N is even, the DC-DC converters comprise a maximum of N/2 DC-DC converters, and
if N is odd, the DC-DC converters comprise a maximum of N/2+½ DC-DC converters.