Overview of different hybrid vehicle architectures

The large boom in the Hybrid Electric Vehicle (HEV) market sector has seen the spread of three main powertrain configurations: Discontinuously Variable Transmission (DVT) parallel architectures, Continuously Variable Transmission (CVT) parallel architectures and series architectures. In particular, CVT powertrains can count the highest number of sales in the HEV industry. In spite of this fact, in depth electrical losses analysis of this configuration and the introduction of more efficient electric component question the adoption of this powertrain as the model of energy efficiency. This paper aims to summarize the main results available in the scientific literature on this topic. It is firstly shown a fuel consumption comparison between the two parallel powertrains, secondly a brief description of the main electric component innovations is reported in order to fully understand the effects they have on the series architectures. Lastly, a fuel consumption comparison between the most efficient parallel solution and the series architecture is shown for the purpose of identifying the most efficient powertrain architecture.