Citation: Wani, M.; Hafiz, F.; Swain, A.; Ukil, A. A Multi-Objective Approach to Robust Control of Air Handling Units for Optimized Energy Performance. Electronics 2023, 12, 661. https://doi.org/10.3390/ electronics12030661 Academic Editors: Akira Otsuki and Pezhman Ghadimi Received: 27 December 2022 Revised: 24 January 2023 Accepted: 26 January 2023 Published: 28 January 2023 Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). electronics Article A Multi-Objective Approach to Robust Control of Air Handling Units for Optimized Energy Performance Mubashir Wani 1, * , Faizal Hafiz 2 , Akshya Swain 1 and Abhisek Ukil 1 1 Department of Electrical, Computer & Software Engineering, The University of Auckland, Auckland 1010, New Zealand 2 SKEMA Business School, Université Côte d’Azur, Sophia Antipolis, 06108 Nice, France * Correspondence: mubashir.wani@auckland.ac.nz Abstract: This paper presents a robust control framework with meta-heuristic intelligence to optimize the energy performance of air handling units (AHUs) and to maximize the thermal comfort of occupants by judiciously selecting the temperature set points of two controllers (i.e., the H ∞ controller and the boiler controller). The selection of these set points is formulated as a multi-objective optimization problem, where the goal is to balance energy consumption with thermal comfort. Furthermore, the uncertainty weights of the H ∞ controller are estimated to minimize oscillations in the outflow air temperature of the AHU plant. The performance of the proposed framework is investigated by considering the real-time weather data of Auckland, New Zealand. The results of the simulation show that the proposed robust control framework could significantly reduce oscillations in the outflow air temperature compared with the conventional case, where the temperature set points are selected empirically. Moreover, annual energy savings of of 49.13% are achieved without compromising the thermal comfort. Keywords: air handling units; energy consumption; multi-objective optimization; occupant comfort; set points 1. Introduction The demand for energy consumption has been increasing at an alarming rate with the increase in world population. To meet this increasing energy demand, a large dependence of the world over the past decade or so has been non-renewable energy resources. This trend is more likely to remain the same in the foreseeable future, even though heavy investments are currently being made in the renewable energy sector. The complication is that the availability of non-renewable resources is scarce. The rate at which they are being consumed presently will make them insufficient for the increasing energy demand in the future. Moreover, their increasing use is also posing a detrimental impact on the Earth’s environment, which includes climate change (global warming), rising sea levels and so on. To become independent from the use of non-renewable resources seems to be feasible. However, this will not be dynamic, as it would take several decades to free ourselves from the use of non-renewable energy resources and completely switch to renewable energy resources [1]. Meanwhile, efficient utilization of the available energy resources can be regarded as a highly capable substitute to address the aforementioned problems, as this will prompt a reduced rate of non-renewable resource consumption [2]. The latest statistical data released by U.S Energy Information Administration (EIA) indicates that over 40% of the energy produced from the world’s resources is consumed by the buildings sector alone, with residential and commercial buildings included, and more than one-third of this energy consumed is utilized for space heating and cooling [3,4]. These statistics give a strong implication that minimizing the energy usage of heating, ventilation and air conditioning (HVAC) systems can be a principal element in realizing the curtailment of world’s energy Electronics 2023, 12, 661. https://doi.org/10.3390/electronics12030661 https://www.mdpi.com/journal/electronics