In everything from electric vehicles to smart grids, including your laptop, smartphone, television, and house, sensors keep track of changing conditions, but they have a couple of limitations.
For the most part, sensors require their own network and power supply, which limits their utilization and capabilities. Implementing smart grids, for example, requires high-speed and high-resolution data that can monitor how much power is going where and when. The problem has to do with installation, something like installing a network to monitor a network, requiring untold time and money to roll out something as simple as a networked current monitor.
Some breakthrough research in the field of portable microsensor technology has led to the development of a single-chip electrical current sensor. About 1 mm thick, the new chip is completely self-powered. Well, actually it is powered by the circuit that it’s monitoring, which is a huge step forward. Since the sensor does not require an external power supply, installation is simpler and, with the addition of wireless transmission, all that is required is a receiver. Of course, the receiver has its own power supply, but central installation makes monitoring even hundreds of sensors far simpler of a task.
Professor Derek Sui-wing Or, of the Department of Electrical Engineering at The Hong Kong Polytechnic University (HKPU), says “Our smart sensors are essentially simple, totally passive and capable of producing large and clear output voltage signals which are 2,000 times higher than the traditional current sensors. This passive and self-sustainable nature allows real-time, nonstop monitoring of the ‘health’ of electrical equipment, including those carrying high voltages, heavy currents and/or strong electromagnetic fields.”
He goes on to explain, “Besides, these smart sensors can be tailored to harvest electromagnetic radiations emitted by the electrical equipment being monitored and to turn them into useful electrical energy. The stored electrical energy can be used to power up microcontrollers, displays, wireless transmitters, etc.” Rolling out a smart grid system, with a self-powered sensor such as developed at HKPU, could be the revolutionary step needed in order to expand its usefulness and sensitivity.
Image © Hong Kong Polytechnic University