General supervisory control policy for the energy optimization of charge-sustaining hybrid electric vehicles

A general formulation of the instantaneous power split strategy between an IC engine and an electric machine in a charge-sustaining hybrid-electric vehicle is given. It is based on the instantaneous optimization of an equivalent fuel consumption. This approach involves a heuristic formulation to convert the electrical power flow into equivalent fuel cost based on the average cost of electricity through the various power paths (present and future). This control strategy was implemented on a HEV prototype and real-world results are presented here, demonstrating that this approach provides excellent fuel efficiency along with robustness and charge sustaining operation. Then, a general and scalable formulation of this control strategy is proposed. (C) 2001 Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved.