Control Co-Design of Automotive Vapor Compression Systems

Vapor compression systems are commonly implemented air conditioning systems in automobiles that must be optimized in order to improve vehicle efficiency and reduce greenhouse gas emissions. This work uses control co-design techniques to simultaneously optimize the plant and control parameters of the system, as opposed to conventional techniques that sequentially optimize these parameters. Control co-design is applied to a dynamic, first-principles-based model of a vapor compression system cooling a car cabin that is controlled by three proportional-integral controllers. A multi-objective optimization problem is formulated to simultaneously optimize the sizing and performance of the system by minimizing component volumes and reducing power consumption. A Pareto curve is provided to demonstrate the trade-offs between these two objectives. Additionally, dynamic simulation results show the optimal designs meet the constraints while improving upon the performance of a design provided by a conventional optimization approach. Control co-design is shown to improve the sizing and performance of the system when compared to a conventional optimization approach.