23 Jul 2024


Vibration-powered generator could shake up the market

Vibration-powered generator could shake up the market

A UK-developed device which turns machine vibrations into energy to power devices such as sensors, processors and transmitters without needing batteries or wired power supplies, has entered production following field trials. One of the main uses for the vibration-harnessing microgenerator is expected to be transmitting condition monitoring measurements from motor-driven equipment.

The technology has been developed by Southampton-based Perpetuum which was set up as a spin-off from the University of Southampton in 2004. Following the recent injection of £2.2m of funding, the microgenerators are being put into production.

The devices will generate up to 5mW – enough to power a wireless transmitter capable of sending 6kb of data every few minutes, or smaller amounts of data – such as temperature readings – several times a second.

The generators – which can be screwed onto equipment or held in place by magnets – are based on a magnet-and-coil arrangement that transforms the kinetic energy of vibrations into electrical energy. Initially, there are four models tuned to operate either at mains frequency (50Hz and 60Hz) or at twice mains frequency (100 and 120Hz), with a bandwidth of ±0.2Hz. They can produce a 400µW output from small vibrations (25mg), or 5mW from 100mg.

In the field trials, the generators have been coupled to the S5NAP remote sensing modules developed the US-based condition-based monitoring specialist, RLW.

In one trial, at Yorkshire Water, six of the modules have been providing vibration spectra and temperature data from pumping equipment and blowers. In a second trial, the US Navy has been using one of the modules to monitor similar data from a compressor. In a third trial, at an unnamed oil company, the modules have been attached magnetically to pump motors and pipework to collect condition monitoring data.

“This is a practical device, not a laboratory experiment,” declares Perpertuum`s chief executive, Roy Freeland (shown above with one of the generators). “No competitive offering has come close to this level of performance in terms of the amount of data that can be sent, or the conditions under which it will operate reliably.”

Perpetuum believes that the generator could make condition monitoring affordable in many applications where wired connections are prohibitively expensive. According to one estimate, the global market for plant asset management and condition monitoring equipment could by worth $1.3bn by the end of 2007, driven, in part, by the widespread cutbacks in maintenance staff.

Perpetuum has developed a special version of its microgenerator to harness 10-25Hz vibrations on board helicopters. At the recent Farnborough Air Show, it announced its first order for this product. The company is also working on other implementations and smaller versions of the generator.