Dither extremum seeking control of a variable refrigerant flow system with equality constraint handling. (25th January 2022)

• Record Type: Journal Article
• Authors: Dong, Liujia; Li, Yaoyu; House, John M.; Salsbury, Timothy I.
• Is Part Of: Science and technology for the built environment. Volume 28:Number 2(2022)
• Page Start: 152
• Page End: 169
• Publication Date: 2022-01-25
• Subjects: Heating -- Periodicals; Ventilation -- Periodicals; Air conditioning -- Periodicals; Refrigeration and refrigerating machinery -- Periodicals; Indoor air quality -- Periodicals; Indoor air quality; Air conditioning; Heating; Refrigeration and refrigerating machinery; Ventilation; Periodicals; 697
• DOI: 10.1080/23744731.2021.1993671
• Languages: English
• ISSNs: 2374-474X

Abstract

Abstract : In this paper, we apply an extremum-seeking control strategy to a variable refrigerant flow (VRF) system, where the total power consumption is minimized by adjusting the compressor discharge pressure setpoint and the outdoor unit fan mass flow rate, incorporating constraints on the zonal temperature setpoint regulation. A simulation study is conducted using a Modelica dynamic simulation model of a VRF system with one outdoor unit and four indoor units. Simulation results validate the effectiveness of the proposed method of power minimization with the constraint of zone-temperature regulation. The ESC strategy incorporates online penalty-weight estimation and loop-gain adaption, which are shown to improve convergence.