F2010A063
A Cost-effective Pneumatic Regenerative Stop-start Hybrid System for Bus and Commercial Vehicle
A cost-effective pneumatic regenerative stop-star hybrid system for bus and vehicle is able to convert braking energy into quantities of compressed air saved in an air tank during deceleration. It saves fuels at every stop by eliminating engine idle, i.e. switch off engine. The air starter implemented in this system uses compressed air to start the engine in every stop/start operation for the biggest fuel saving. The system remains standard vehicle transmission and low cost modification to the engine.
In order to reuse the residual kinetic energy, the vehicle operation consists of 3 basic modes, i.e. compression mode, cranking mode and normal firing mode. During deceleration, the engine switches firing mode to compression mode and stops fuel injection. Both intake valves utilize the variable valve exhaust brake (VVEB) technology to be able to keep them jam in certain lift in compression mode. In compression stroke, the induced air could be compressed through the opening gap of intake valves into the air tank.
A six-cylinder YUCHAI YC6A 7.25 litre diesel engine equipped with additional proven technologies has been modelled as an air hybrid engine by using Ricardo's WAVE software. For a 150 litre air tank, it takes 240th engine revolutions for charging the air tank pressure from 1 bar to 6 bar (9.6 seconds at 1500 rpm engine speed). It can provide 2-second crank time to start the engine by using the air starter. Therefore, fuel consumption could be saved in deceleration and engine idle by using the cost effective pneumatic regenerative stop-star hybrid system.
This abstract is supplemented by a PDF, which can be viewed here.
Session: Alternative Drivelines