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Faculty of Social Sciences

PhD defence by Anders Overgaard


27.05.2020 kl. 09.00 - 11.00


“Reinforcement Learning for Building Heating via Mixing Loops”

Large operating cost and the often considerable potential for energy savings drives continuousresearch within control of heating, ventilation and air-condition (HVAC). Mixing loop is a HVAC subsystem, where temperature and pressure of the heat transporting water, in a building or zone, can be controlled. To minimize energy consumption, while keeping heating comfort in the building, the control of the mixing loop needs to be tailored for the specific HVAC system and building. A data driven control method within the field of Reinforcement Learning (Approximate Dynamic Programming) is proposed. A large sensor pool and data gathered from the internet is used to improve performance. To maintain a high learning rate a method based on partial mutual information has been developed to identify which data nodes gives high performance while keeping the dimensionality low. One of the major problems in mixing loop control is that long flow dependent transport delays occur. In this work a flow compensation is added to improve both the self-learning control and the selection of input variables.

Results from a hardware in the loop setup, involving a mixing loop in connection with a developed building emulator, shows promising performance improvements in comparison with commercially available controllers within a feasible learning period. The project has been carried out under the Danish Industrial PhD programme and has been financed by Grundfos Holding A/S together with the Danish Foundation of Innovation. Supervision of the project has been from Controls within Grundfos Holding A/S and the department of Automation and Control at Aalborg University.

Assessment Committee
Senior Manager, Lars Finn S. Larsen, DANFOSS, Denmark
Dr. Joaquim Blesa Izquierdo, Universitat Politècnica de Catalunya, Spain
Professor, Jan Østergaard, Aalborg University (Chairman)

Associate Professor, Jan D. Bendtsen, Aalborg University, (main supervisor)
Professor Carsten Skovmose Kallesøe, Ph.d. Brian K. Nielsen, Ph.d. Hakon Børsting -Grundfos Holding A/S

Associate Professor, Kirsten M. Nielsen, Aalborg University


Automation and Control Section, Department of Electronic Systems


Online via MS Teams - link will be provided upon registration.

Registration Deadline

25.05.2020 kl. 12.00

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