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Optimization-based strategy planning for predictive optimal cruise control has the potential for significant improvements in passenger comfort and fuel efficiency. It is, however, associated with a high computational complexity that complicates its implementation in an electronic control unit. When implementing predictive cruise control, real-time capability must be ensured while maintaining optimal control performance in the presence of disturbance and model uncertainty. Real-time capability can be achieved either by a significant simplification of the optimization problem or by a layered control approach, combining the strategy planner with a low-level controller. Both approaches, however, are prone to deteriorate optimal control performance, particularly in the presence of disturbance. We present a model-predictive controller structure that extends the layered control approach by using the same optimization algorithm on two layers.

Rising oil prices and increasing strict emission legislation force vehicle manufacturers to reduce fuel consumption of future vehicles. In order to meet this target, the process of converting fuel into useable energy and the use of this energy by the different energy-consuming vehicle's subsystems have to be examined. Vehicles' subsystems consist of energy-supplying, energy-consuming, and in some cases energy-storing components. Due to the high complexity of these systems and their interaction, optimization of their energy efficiency is a challenging task. By introducing individual operational strategies for each subsystem, it is possible to increase the energy efficiency for a specific function. To further improve the vehicle's overall energy efficiency, holistic control strategies are introduced that distribute the energy between the subsystems intelligently.

Steadily rising energy prices and increasingly strict emissions legislation enforce the development of measures that increase efficiency of modern vehicles. An important contribution towards more efficient vehicles is the introduction of measures regarding auxiliary units. These measures increase the gross efficiency of a vehicle and therefore also the vehicle's range. Among the auxiliary power units of a vehicle like a long-haul truck, the refrigerant compressor generally consumes the biggest amount of energy. Therefore, it is reasonable to focus efficiency-increasing efforts on optimizing the A/C system. An important tool used in the development of optimization approaches is the simulation of the relevant systems. This allows a cost-optimized evaluation of the optimization approaches and also lets the engineer compare multiple variations of these approaches within a short period of time.