Remotely controlled photovoltaic string combiner
AssigneeKoolbridge Solar, Inc.
InventorPaul Wilkinson Dent
Life of this patent
Estimating the term…
Abstract
A remote-controlled photovoltaic string combiner is described that selects strings to be combined to a first photovoltaic output circuit or to a second photovoltaic output for the purpose of either controlling the charging of a battery connected to the first photovoltaic output circuit or for diverting current to a diversion load such as a grid-tie inverter. Strings are selected by energizing relays from one or other inverter such that when neither inverter is operating, all strings are deselected and both photovoltaic outpout circuits are de-energized.
Claims19
A remote-controlled string combiner configured for use in a photovoltaic energy collection system to combine the photovoltaic source circuit current from strings of solar cells to produce a combined output current in the photovoltaic output circuit, comprising:—
- Pairs of positive and negative input terminals for receiving photovoltaic source-circuit current from respective strings of photovoltaic cells connected thereto;
- a first pair of positive and negative output terminals for the connection of the photovoltaic output circuit wiring and for outputting the combined source circuit current from said strings to a remote load connected to said photovoltaic output circuit;
- at least one connector or suitable terminals for the attachment of at least one remote control cable;
- at least one relay having normally open contacts, the control coil of said relay being wired to receive an electrical energizing signal along said at least one remote control cable from a remote power source, the energizing signal when present causing said normally open contacts to close, thereby allowing said combined source circuit current to be output from said first pair of positive and negative output terminals of said photovoltaic output circuit, and the combined source circuit current being inhibited from being output to said photovoltaic output circuit when said energizing signal is not present.
A remote-controlled string combiner configured for use in a photovoltaic energy collection system to selectively combine the photovoltaic source circuit current from strings of solar cells to produce a combined output current in one or more photovoltaic output circuits, comprising:—
- Pairs of positive and negative input terminals for connecting to respective ones of said strings of solar cells;
- a first pair of output terminals for the connection of photovoltaic output circuit wiring, the photovoltaic output circuit receiving the combined source circuit current from selected strings;
- a pair of fuses connected at their first ends to the positive and negative terminals respectively of each of said pairs of input terminals and connected at their second ends to a snubber circuit, the snubber circuit comprising a capacitor in series with a diode and the diode being shunted with a resistor, the second ends of the fuses also being connected to the moving contacts of a two pole relay through a diode, the two pole relay having normally open fixed contacts connected together to said pair of output terminals;
- a connector or suitable terminals for the connection of a remote control cable, the coils of said two-pole relays being selectively energized through said remote control cable in order to select the strings, the photovoltaic source current of which shall be combined at said first pair of output terminals.
A photovoltaic string combiner configured to be mounted as close as possible to a solar array for selectively combining the currents from strings of the array to be output to a photovoltaic output circuit under control from a remote location via a remote control cable by receiving relay coil energizing currents from a power source at said remote location, and further configured such that when no relay coil energizing currents are received from said remote power source, no string currents are selected to be combined and said photovoltaic output circuit is thereby de-energized.
A method of rapidly de-energizing the Direct Current wiring leading from a solar array to a remote load, including the steps of:—
- Configuring a photovoltaic string combiner to be located in close proximity to said array and facilitating the connecting of each string of solar cells of said solar array to input terminals of said combiner;
- providing said photovoltaic combiner with a pair of output terminals for connecting the combiner output to said remote load;
- within said photovoltaic string combiner, providing a pair of normally open relay contacts in series with the input from each string of solar cells of said solar array such that no input current from any string reaches said output terminals unless at least one of said relays is energized to close its normally open contacts;
- providing said photovoltaic combiner with a remote control interface for a remote control cable to supply energizing current to the coils of said relays from a remote power source;
- configuring said remote control interface such that the current to all relay coils may be interrupted simultaneously by any one of a number of switches located at any one of multiple locations, including a switch located on said photovoltaic combiner itself;
- a switched co-located with said remote load, and a switch located at the service entrance for power from an electric utility.
A residential photovoltaic energy installation comprising:—
- Solar panels attached to a sun-facing roof;
- a remote controlled photovoltaic string combiner located in the attic space of said roof directly under said solar panels for selectively combining currents from selected strings of solar panels under remote control via a remote control cable and providing the combined current at a photovoltaic output circuit connected to a remote load, and
- a DC to AC inverter for converting DC power originating from said solar panels to AC household current, said DC to AC inverter being connected via said remote control cable to said string combiner and configured such that, when said DC to AC inverter is off, no string of solar panels is selected to be combined to said photovoltaic output circuit and the photovoltaic output circuit is thereby de-energized.
Dependencies are inferred from the claim text.