28 May 2014
TOYOTA TAKES NEXT STEPS IN HYBRID POWER
Toyota is undertaking significant developments in the laboratory and on the race track to advance future generations of hybrid vehicles such as Prius and Camry.
The world’s largest producer of petrol-electric hybrid vehicles is targeting gains to performance and fuel efficiency that will extend its lead in hybrid technology.
In Japan, Toyota has announced a new generation of computer chips with the potential to boost the fuel efficiency of its hybrid vehicles by 10 per cent* while significantly reducing the size of the crucial power control unit (PCU).
Meanwhile, its Toyota Racing division based in Germany is focused on bringing hybrid know-how to road cars from its participation in the World Endurance Championship (WEC) sports-car racing, including next month’s Le Mans 24-hour classic.
Toyota Racing is pushing the limits of hybrid technology in motorsport with its new all-wheel-drive TS040 Hybrid race car that harvests more braking energy that can be stored and used under acceleration to deliver a significant power boost.
Compared with last year’s race car, the maximum power of the TS040 Hybrid has increased more than 18 per cent while fuel use has been cut by 25 per cent.
Toyota Racing president Yoshiaki Kinoshita said the TS040 Hybrid – victorious in the two WEC races already held this year – acts as a real-life test bench for Toyota’s latest hybrid concepts.
“We are competing in order to test the latest hybrid technology in the most extreme motorsport environments, and this has a direct influence on future road-car technology,” Mr Kinoshita said.
Know-how from the motorsport program and Toyota’s on-going research and development has already been used to enhance the company’s hybrid road cars with more than six million sold around the world since the launch of the first Prius in 1997.
The latest laboratory breakthrough announced by Toyota involves new silicon carbide computer chips (power semi-conductors) that are substantially more efficient than today’s chips made from silicon alone.
Designed to be used in the PCU of hybrid vehicles, they will enable Toyota to improve fuel efficiency by up to 10 per cent while also reducing PCU size by up to 80 per cent.
The newly developed silicon carbide chips – which will undergo on-road testing in Japan within a year – reduce the amount of current lost as heat, and switch the current flow on and off more efficiently.
This enables the coil and capacitor, which account for approximately 40 per cent of the size of the PCU, to be reduced in size.
The PCU in hybrid vehicles supplies electric power from the battery to the motor to control vehicle speed. It also sends electricity generated through deceleration to the battery for storage.
An estimated 20 per cent of the total power loss in hybrid vehicles is associated with the power semiconductors alone. Therefore, a key way to improve fuel efficiency is to improve power semi-conductor efficiency.
Toyota is developing the new chips in collaboration with Toyota Central R&D Labs Inc. and Denso Corporation, the Toyota group’s largest parts supplier.
Since launching Prius, Toyota has been working on in-house development of power semiconductors and on improving hybrid-vehicle fuel efficiency.
In December last year, Toyota established a clean room for dedicated development of silicon carbide semi-conductors at its Hirose Plant in Japan, which is a facility for research, development and production of devices such as electronic controllers and semi-conductors.
The Le Mans 24-hour race will be run on June 14-15. A test day on June 1 is followed by scrutineering on June 8-9 and qualifying on June 12.