As the voltage generated by solar panels increases, the risk of explosion or lightning caused by high-power discharge caused by wire damage is also increasing. In order to reduce or eliminate this risk, researchers at Sandia National Laboratory, in cooperation with engineers of guardian sensors Inc., have developed an electrical online connector, which can automatically predict and prevent electrical fires caused by photovoltaic arc faults.
The online connector developed by the team is about an inch long and a dime in diameter. It contains a metal spring covered with a self extinguishing polymer material developed and tested by Sandia over the past five years. It can replace the current connector and connect a series of solar panels, which can work together in the field or on the roof.
If a spark occurs, the polymer in the in-line connector melts and the spring extends inside it, expanding the spark gap and stopping the flame, as shown in the figure.
All connectors are vulnerable to corrosion, damage or improper installation, which may lead to unreliable problems – especially if the wires have small gaps or breaks. In traditional connectors carrying high current and high voltage, these defects will produce sparks and fire. The connector is not protected.
The new in-line connector is designed to activate at temperatures above 185 ° F. At this time, the self extinguishing polymer will melt, fill the gap or fracture of the wire, and the spring will expand. This expands the spark gap between wire conductors, which no longer produce the energy that causes heat and fire. The reaction rate and the fire resistance of the polymer can stop the fire before it starts — less than two seconds.
Sandia can provide Guardian sensors with patented special arc fault generators tested in the laboratory. It was developed by researchers to try to determine how dangerous arc faults are; It can also test the reliability of different materials in high voltage connectors and wires. It is used to test the prototype of the new on-line connector.
In the future, the device can be used for other types of power supply and storage devices, such as batteries.
Post time: Jul-31-2021