Control Co-Design of a Thermal Management System with Integrated Latent Thermal Energy Storage and a Logic-based Controller

Thermal energy storage (TES) devices are increasingly being used for improving the transient response of thermal management systems (TMSs). However, the design of the TES device and system-level controller are typically siloed, which is problematic given that a component-level optimized TES design might not be the optimal design to meet system-level requirements like preventing critical components from overheating. An alternative approach is to design both the TES and the system-level feedback controller simultaneously with a process known as control co-design (CCD). In this paper, we consider a TMS with integrated TES (also known as a hybrid TMS) in which the system mass flow rates are determined by a logic-based controller. We first perform a sensitivity analysis to determine those TES and controller parameters that most affect the system-level objectives of interest. We then formulate and solve a design optimization problem that leverages a pseudo-objective function formulated to quantify said system-level thermal management objectives. The results are benchmarked against those of a comparable hybrid TMS whose TES is optimized only using component-level performance objectives. We demonstrate that while CCD is sensitive to the expected heat load considered during the optimization process, the coordinated optimization of the TES and system controller parameters leads to improved system-level performance than that achieved using a TES design optimized separately.