Author:

Keywords:

Science & Technology, Technology, Construction & Building Technology, Energy & Fuels, Engineering, Civil, Engineering, Model predictive control (MPC), Grey-box models, Field test, Validation, Modelica, ENERGY, 09 Engineering, 12 Built Environment and Design, Building & Construction, 33 Built environment and design, 40 Engineering

Abstract:

This contribution presents the results of different MPC's applied in a real office building in Brussels, Belgium. The building is a medium-sized office building with two floors and a total size of 960 m². The controllable system is the hybrid heat production consisting of two air/water heat pumps and a condensing gas boiler. The practical situation does not allow controlling end-units in the different thermal zones. To test and compare different MPC implementations in a fair way (thus having identical conditions), a real building is not sufficient. Therefore, an emulator model is developed with sufficient detail to consider it as a virtual copy of the real office. Most experiments are performed on the emulator, and the promising controls are implemented in the real building. The MPC makes use of grey-box models (see abstract entitled Automated identification of grey-box controller models for monitored buildings with JModelica.org) and solving of the optimal control problem (OCP) with JModelica. The OCP may be linear, non-linear and time-discrete. The experiments cover differences with regard to model complexity, objective functions, constraints, discretizations and time horizons. The presentation will briefly cover the aspects of monitoring, model identification, forecasting of disturbances, state estimation, solving the OCP and sending of the control signals. More time will be devoted to the results. The different MPC strategies are analysed quantitatively with regard to energy use, thermal comfort and numerical properties. Real-life issues with regard to practical implementation are also presented.