Tiny sensor for electrical fault detection
In response to the call for reliable monitoring activities for electricity transport, Prof. Derek Or Siu-wing and his research team at the Department of Electrical Engineering have developed smart sensors of only 1 mm in thickness to detect electrical currents. The sensor chips can be placed on sensing points of interest such as electrical cables, conductors, junctions and bus bars. Made from rare earth multiferroics with giant magnetoelectric properties, these chips enable the direct detection of magnetic fields generated by electricity and the linear conversion of those fields into electrical voltage signals.
Also known as "self-sustainable magnetoelectric smart sensors", the sensors do not use the power supplies and signal conditioners generally required by traditional current sensors. As they do not have power cords and active electronic components, they can be conveniently, safely and reliably used for early fault detection.
The smart wireless sensors allow the real-time, nonstop monitoring of the health of electrical equipment and can reach hard-to-access locations such as rails, tunnels and underground premises. They are also environmentally sustainable – with energy harvesting technology, electromagnetic radiation emitted by the electrical equipment being monitored can be turned into useful electrical energy.
In future, the research team will be working to make the sensors even more sensitive and reliable in measurement. ♦
