VVT in combination with hybridization: how to size the components and what are the benefits?

What is it about?

The electric hybridization of vehicles with an internal combustion engine is an effective measure to reduce CO2 emissions. However, the identification of the dimension and the sufficient complexity of the powertrain parts such as the engine, electric machine, and battery is not trivial. Here, we look into the effect of fully variable valve timing on the sizing of a hybrid electric power train.

Featured Image

Photo by Michal Matlon on Unsplash

Photo by Michal Matlon on Unsplash

Why is it important?

Internal combustion engines have to be ideally as flexible as possible to maximize efficiency, compatibility with (future) fuels and minimize pollutant emissions. One degree of flexibility is the gas exchange: it is classically performed with a camshaft-driven system with only limited degree of flexibility. Here, we look on the effect of a fully flexible gas exchange system using electrohydraulic valve actuation which enables new features like ideal load control, flexible cylinder deactivation or even extended-stroke / skip fire operation. It is well known that fully flexible valves are a potent measure to optimize spark ignition engine efficiency and performance in classical configurations. Here, we answer the question how much gain can be expected with such a valvetrain in a hybrid-electric passenger car configuration.

Perspectives