Design and Control of Commuter Plug-In FC Hybrid Vehicle 2007-24-0079
Strong dependency on crude oil in most areas of modern transportation needs lead into a significant consumption of petroleum resources over many decades. In order to maximize the effective use of remaining resources, various types of powertrain topologies, such as hybrid configurations among fuel cell, electric battery as well as conventional IC engine, have been proposed and tested out for number of vehicle classes including a personal commuting vehicle. In this paper the vehicle parameters are based on a typical commercial sub-compact vehicle (FIAT Panda) and energy needs are estimated on the sized powertrain.
The main control approach is divided in two categories: off-line global optimization with dynamic programming (DP, not implementable in real time), and on-line Proportional and Feed-Forward with PI controllers. The proposed control approaches are developed both for charge-sustaining and charge-depleting mode and sample results are shown and compared.
The Plug-in FCHEV can draw electricity either from a power grid line or from a personal eco-system that is completely independent from the conventional power grid line. Especially in the latter case, a well designed hybrid wind/photovoltaic generating system may supply the powers to the user in a self-sustaining mode and possibly some extra powers especially during the nights. Under this scenario, a smart power management system supervises the energy flows and optimizes the charging schedule taking into account time variations of the demand and the time variation of energy prices as well as the conversion efficiency. Thus, the ultimate goal of minimizing the energy cost and the dependency on the grid can be achieved.
As a proof of concept, although the vehicle is not the same class of the study, a commercial 3.5 kW neighborhood electric vehicle has been modified to become a Plug-in Hybrid FCNEV with an air-cooled PEMFC power system, NiMH battery modules and a bidirectional DC/DC converter. The conclusions of this paper can be extended to a typical sub-compact passenger vehicle which may satisfy traditional automotive consumers’ expectation.