Model predictive control of a waste heat recovery system for automotive diesel engines

In this paper, a switching Model Predictive Control strategy is designed for an automotive Waste Heat Recovery system with two parallel evaporators. The objective is to maximize Waste Heat Recovery system output power, while satisfying safe operation under highly dynamic disturbances from the engine. Safe system operation is associated with vapor state after the evaporators. The closed-loop performance of the Model Predictive Control strategy is demonstrated on a high-fidelity validated Waste Heat Recovery system model subject to realistic disturbances from an Euro VI heavy-duty diesel engine. The simulation results, based on a World Harmonized Transient Cycle, demonstrate that the proposed control strategy outperforms a classical PI control strategy in terms of safety and relative average power, up to 15% and 3%, respectively.