Distributed Economic Nonlinear Model Predictive Control for Flexible Electrified Biodiesel Production─Part II: Sequential and Iterative Architectures with Computational Delay Compensation

We present a distributed economic nonlinear model predictive control (DeNMPC) framework with computational delay compensation for flexible biodiesel production, exploring both sequential and iterative communication architectures. Notably, our control scheme incorporates delay compensation over multiple sampling time intervals, addressing subsystem couplings in distributed control. Through closed-loop simulations, we demonstrate that computational delays can significantly impact the stability and performance of DeNMPC strategies. Particularly, the sequential approach shows considerable discrepancies in control performance when comparing ideal computational conditions with those accounting for computational delay. Our results reveal that the iterative architecture, with bidirectional communication and iterative optimization, outperforms the sequential approach, providing higher energy cost savings and greater adaptability to disturbances. This work contributes to advancing DeNMPC applications with delay compensation techniques, underscoring their potential for sustainable biodiesel production and possible extensions to other chemical processes.