Series hybrid electric vehicle supervisory control based on off-line efficiency optimization

A supervisory control system (SCS) is developed for a dynamic model of a series hybrid electric vehicle. The powertrain steady-state behavior is analyzed to produce a control map offline which maximizes the vehicle energy efficiency for any driving condition. This map can be accessed on a real-time basis during driving at low computational cost to locally optimize efficiency. The vehicle transient response is considered to ensure efficient, stable and healthy operation. Simulations using standard drive cycles verify that the designed Efficiency Maximizing Map (EMM) control allows smoother operation of the powertrain and it brings reductions in fuel consumption as compared to a Thermostat control scheme.