Low-‎computational adaptive MPC algorithmization strategy for over ‎and ‎undershoots ‎instantaneous ‎water ‎heaters stability

Year 2023, , 19 - 24, 22.06.2023

Ismael Ehtiwesh

https://doi.org/10.14744/seatific.2023.0003

Abstract

Tankless gas Hot Water users' ‎comforting perception ‎is severely affected by ‎sudden ‎changes ‎in temperature ‎apart from ‎the ‎desired temperature. The instability of the ‎water ‎temperature ‎with ‎overshoots and ‎undershoots is the ‎most common disadvantage ‎that ‎appears ‎mainly ‎because of the sudden changes in ‎the water flow demanded by ‎users ‎and ‎the ‎response delays inherent to ‎the heating system. ‎Classical ‎controllers for heat ‎cells have ‎difficulties in ‎responding ‎to ‎temperature ‎instability in a timely manner because ‎they do not ‎have the ‎capacity to anticipate ‎the ‎effects ‎of sudden variations in water flow ‎rate. ‎The ‎model ‎predictive control with adaptive function strategy reported ‎the ‎best ‎response ‎in ‎the stabilization of ‎temperature ‎in previous work. Its ‎performance is a ‎result of ‎the ‎predictive nature that allows ‎anticipating and ‎correcting the negative ‎influences ‎of ‎sudden ‎variations in the flow rate in ‎the ‎temperature. The present study aims to employ ‎this ‎strategy a low-computational ‎algorithm that can be embedded in low-cost ‎hardware ‎with ‎the limitation of computational and ‎memory resources. ‎The ‎study’s ‎motivation is to ‎meet ‎the ‎opening of manufacturers by ‎implementing low-cost and optimal-‎performance ‎microcontrollers ‎for ‎water heaters. The algorithm predictions ‎are ‎showing ‎good ‎agreement ‎responses in temperature stabilization.‎

Keywords

Tankless hot-water stability, predictive control, adaptive ‎function, low-computational ‎microcontroller, time delay‎

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