Cars built by European firms such as Peugeot and Porsche could soon be fitted with a UK-developed engine technology that is claimed to greatly reduce emissions and increase performance.
Cambridge R&D company Camcon has developed a proprietary system called Binary Actuation Technology (BAT), which can capture and recycle the kinetic energy of a moving actuator. While the technology has a number of initial applications, its primary use will be to electronically control the opening and closing of valves in a next-generation internal combustion engine that has no camshaft.
BAT not only recycles kinetic energy but also uses very little energy in the process. Before the car's engine computer triggers any action, potential energy is stored in the actuator by means of a powerful magnet that locks it in place. A single electric pulse can disrupt the magnetic force for a microsecond, releasing the built-up energy and flinging the actuator from one stable state to another.
According to Wladyslaw Wygnanski, BAT's inventor and Camcon's founder, this simple 'catapult' effect is very effective at reclaiming energy. 'Eighty per cent of the energy is stored inside the actuator so you just need a very short electric pulse to trigger the action,' he said. 'As this effect sends the actuator from one stable state to another, no electric current is needed to hold it in position, making it extremely efficient.'
Unique benefits
Wygnanski's BAT technology was originally conceived as an idea for the aerospace industry to control jet engines and is covered by 30 patents with another 28 in the pipeline.
The system is said to have a number of unique benefits that make it ideal for use in electronically-controlled engines. First, it is said to have a short reaction time, measured in the laboratory to be able to switch from one state to another within 100 microseconds. As no power is needed to hold it in either stable position it is also energy-efficient.
Another, perhaps less obvious, advantage is a result of the system reclaiming kinetic energy, according to Wygnanski. 'As it lands in position it is extremely gentle — there is no hammering,' he said. 'This means we don't get the fatigue and stress of other systems.'
Camcon has been developing technologies that use BAT for use in the oil and gas industry to control pipeline flow, among other applications. However, Wygnanski said the system is ideally suited to work with digital valves in car engines. This form of Intelligent Valve Actuation means the operation of these inlet and exhaust valves need no longer depend on the crank position; the timing of each can be controlled by the car's engine management computer. Coupled with Camcon's BAT, it should be possible to control the valves' movement with an unprecedented degree of control.
'BAT will give you absolute freedom about when the valves are open and closed with microsecond control,' said Wygnanski.
The technology also means each valve can be held in a number of intermediate positions, independently from other valves, providing even more flexibility.
According to Camcon, using BAT in this way could substantially reduce the amount of unburnt gases, exhaust fumes and noise. Wygnanski said carbon monoxide and nitrous dioxide emissions could be reduced by as much as 20 per cent.
The EU has fixed a deadline of 2012 for reducing vehicle emissions and Wygnanski believes that to get Camcon's system into production vehicles by that time, a prototype engine will have to be developed by 2009. It is in discussions with Peugeot, Renault and Porsche, with Peugeot said to be at advanced stage in its evaluation of the technology.
The firm had already signed an agreement to develop the technology with MG Rover before it went into liquidation, and Camcon has recently received a £200,000 grant from the East of England Development Agency to take it further.
Gases to be cut
BAT is not the first idea for a camless internal combustion engine. Other electronically-controlled valve systems in early stages include the 2007 Mercedes C-Class, which has yet to disclose how it will be operated, and hydraulic-based technology developed by Lotus.
But Wygnanski said these systems — despite their many benefits — lack BAT's efficiency, as they are unable to stop at intermediate stages or use too much power. Hydraulic-based systems such as that developed by Lotus are said to be inefficient and slow to react in cold weather, said Camcon.
'The competition exists, but I am quite sure we are well ahead in terms of performance,' said Wygnanski. 'There really is no time to lose.'
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