Nonlinear-Control Strategy for Advanced Vehicle Thermal-Management Systems

Advanced thermal-management systems for internal combustion engines can improve coolant-temperature regulation and servomotor power consumption by better regulating the combustion process with multiple computer-controlled electromechanical components. The traditional thermostat valve, coolant pump, and clutch-driven radiator fan are upgraded with servomotor actuators. When the system components function harmoniously, desired thermal conditions can be accomplished in a power-efficient manner. In this paper, a comprehensive nonlinear-control architecture is proposed for transient-temperature tracking. An experimental system has been fabricated and assembled which features a variable-position smart valve, variable-speed electric water pump, variable-speed electric radiator fan, engine block, and various sensors. In the configured system, the steam-based heat exchanger emulates the heat generated by the engine's combustion process. Representative numerical and experimental results are discussed to demonstrate the functionality of the thermal-management system in accurately tracking the prescribed temperature profiles and minimizing electrical power consumption.