As hybrids and plug-in hybrids make up a significant share of vehicle sales, automakers are refining the balance between electric and combustion power. Ford has filed an interesting new patent with the European Patent Office, for a new way of transitioning between electric and combustion power, with the electric motor spinning up the combustion engine to make for a smoother transition between the power sources.
Refining Hybrid Transitions: Ford’s Smoother Power Shift
Current Systems Can Be Unrefined
Ford’s patent isn’t about boosting performance or fuel economy, but about making the switch between electric and gas power smoother and less jarring. In many hybrids, this transition can feel abrupt, with a sudden surge in noise and vibration as the silent electric motor hands over to the combustion engine, which fires up instantly to provide assistance.
Blending Power Sources
Instead of the traditional method where the gas engine starts up from a dead rest with a burst of revs to provide power to the wheels, Ford’s system first spins it up using the electric motor to get it up to speed before engaging. At some point, the fuel injection and ignition are precisely timed to engage, allowing the combustion engine to take over seamlessly while the electric motor gradually reduces its input.
Key Advantages
There are several advantages to this new power-handover regime:
- Quieter and smoother transitions between power sources
- No engine shake when the gas engine is set in motion
- Seamless increase in power as the two power sources switch places
- No sudden increase in torque output that can cause driveline snatching
Balancing Refinement and Efficiency
Ford says that the transition is managed and timed for the utmost refinement, but it doesn’t say whether this comes at the expense of fuel efficiency, especially given that electric power is used to spin up the gas motor before it ignites. We suspect most people would be willing to trade a small decrease in fuel economy for a smoother, more refined driving experience.
