Engine On/Off Optimization for an xHEV during Charge Sustaining Operation on Real World Driving Routes Using Connectivity Data

Document Type

Technical Report

Publication Date



Department of Mechanical Engineering-Engineering Mechanics


This paper presents a methodology that optimizes the periods of engine operation on a selected route for a Plug-in Hybrid Electric Vehicle (PHEV) or Hybrid Electric Vehicle (HEV) using Connected Vehicle data to minimize energy consumption. The study was conducted using a Reduced-Order Powertrain model of second-generation Chevrolet Volt. The method utilizes the Backward Induction Dynamic Programming algorithm to come up with an optimal control mode matrix of engine operation along the selected route for various battery states of charge. The objective of this method is to make use of Vehicle Connectivity to minimize the energy utilization of an HEV by using the speed and elevation profile of a selected route transmitted to the vehicle via V2X communication systems. The study focuses on reducing the energy consumption of an xHEV (mostly calibrated for EPA Drive Cycles), on real world driving routes having undulating road profiles with varying speeds for which the vehicles have not been calibrated. The energy savings from the optimizer is dependent on the selected driving route. The energy savings on real world drive routes ranges from 4.5% on an 80 km drive route (mostly highway) with minimal vehicle stops to 11.1% on a 20 km long Urban Drive cycle with a number of vehicle stops. From analyzing around 70 Real-World drive cycles, the optimizer predicts an average energy savings of 7.4% in real world driving scenarios. While on the EPA drive cycles, the energy savings ranges from 11.2% on the UDDS, urban driving scenario with a number of stops, to -1.1% on the highly aggressive US06 drive cycle with fewer stops.

Publication Title

SAE Technical Papers