Electric compressor could double output of hydrogen fuel cells

A UK-based technology company has developed a new electric compressor design, which could double the output of a hydrogen fuel cell.

Fuel cells require a constant source of oxygen to sustain the chemical reaction that they use to release positively charged hydrogen ions. Supplying the hydrogen at high pressure is not generally a problem, but the flow of air can be a limiting factor.

“Our proprietary high speed motor and control technology allows us to deliver air at a much higher pressure [than existing systems],” said Bryn Richards, Aeristech CEO. “No other motor control arrangement is able to deliver at this pressure with such a high efficiency.”

The company has yet to release specific technical details, but the system is understood to use a sophisticated control system capable of maintaining a very consistent torque output. This allows the motor to be powered directly by the fuel cell without the use of an intermediate voltage regulator. Furthermore, Aeristech has claimed the new design could cut the mass of a complete motor, compressor and control unit package by as much as 70 per cent.

“Traditional switched reluctance type high-speed motors would be unable to operate continuously at such high continuous power levels because of thermal management issues,” said Richards. “Our competitors tend to use heavy low-speed permanent magnet motors with step-up transmissions to run their compressors, which creates a bulky system.”

In 2011 Aeristech was one of 14 uk companies funded by Innovate UK to carry out feasibility studies into the development of disruptive low-carbon vehicle technology. This contributed to the development of a 10kW compressor, which is currently undergoing testing. The results of the study are expected to be released by the end of the year.