Distributed power harvesting systems using DC power sources
A distributed power harvesting system including multiple direct current (DC) power sources with respective DC outputs adapted for interconnection into a interconnected DC power source output. A converter includes input terminals adapted for coupling to the interconnected DC power source output. A circuit loop sets the voltage and current at the input terminals of the converter according to predetermined criteria. A power conversion portion converts the power received at the input terminals to an output power at the output terminals. A power supplier is coupled to the output terminals. The power supplier includes a control part for maintaining the input to the power supplier at a predetermined value. The control part maintains the input voltage and/or input current to the power supplier at a predetermined value.
1. A junction box comprising:
an input conductor configured to receive a first power from a first solar panel;
a downstream connector configured to receive a second power from a second solar panel;
an upstream connector configured to output load power sourced from the first power and the second power; and
an internal circuit interface comprising an internal input connected to the input conductor and to the downstream connector and configured to receive the first power and the second power, and an internal output connected to the upstream connector and configured to output the load power to the upstream connector, the internal circuit interface being configured to receive a removable bypass link in a first configuration and a removable power converter in place of the removable bypass link in a second configuration.
2. The junction box of claim 1 , further comprising the removable power converter, wherein the junction box is configured in the second configuration.
3. The junction box of claim 2 , wherein the removable power converter is configured to convert the first power to the load power at the upstream connector.
4. The junction box of claim 2 , wherein the removable power converter is configured to perform maximum power point tracking.
5. The junction box of claim 2 , wherein the removable power converter is configured to evaluate voltage and current at the internal input and provide current and voltage information to a monitoring and logging module.
6. The junction box of claim 1 , further comprising the removable bypass link, wherein the junction box is configured in the first configuration.
7. The junction box of claim 6 , wherein the removable bypass link is configured to directly transfer the first power to the load power at the upstream connector.
8. A junction box comprising:
a first input conductor configured to connect to and receive power from a first solar panel;
a second input conductor configured to connect to and receive power from a second solar panel;
an output conductor configured to connect to at least one of a second junction box and a third solar panel, wherein the output conductor provides a connection to photovoltaic power received from the first solar panel and the second solar panel; and
a chamber configured to receive one of:
a retrofit power converter, and
a removable bypass link directly connecting the first input conductor to the output conductor.
9. The junction box of claim 8 , further comprising the retrofit power converter.
10. The junction box of claim 8 , further comprising the removable bypass link.
11. The junction box of claim 8 , wherein the retrofit power converter is configured to perform maximum power point tracking.
12. The junction box of claim 8 , wherein the retrofit power converter further comprises one or more bypass devices, each bypass device coupled to a string of solar cells of the first solar panel.
13. The junction box of claim 12 , wherein the bypass devices are transistors.
14. A junction box comprising:
a first pair of input terminals;
a second pair of input terminals;
a pair of output terminals; and
a power converter having first and second internal input terminals coupled to at least one of the first pair of input terminals and the second pair of input terminals,
wherein the junction box is configured to receive a first photovoltaic power at the first pair of input terminals and a second photovoltaic power at the second pair of input terminals and provide a converted output power at the pair of output terminals.
15. The junction box of claim 14 , wherein the power converter is configured to perform maximum power point tracking.
16. The junction box of claim 14 , wherein the power converter is configured to evaluate voltage and current at each of the first and second internal input terminals and provide current and voltage information to a monitoring and logging module.
17. The junction box of claim 14 , wherein the junction box is configured to be mounted on a photovoltaic panel or a frame.
18. The junction box of claim 14 , wherein the power converter is detachable from the junction box, and the junction box is configured to receive a bypass link when the power converter is detached.
19. The junction box of claim 14 , wherein the first pair of input terminals are connected in parallel with the second pair of input terminals and with the first and second internal input terminals.
20. The junction box of claim 14 , wherein the junction box is configured to be integrated in a solar panel.