Thermal circuits assembling and state-space extraction for modelling heat transfer in buildings

TL;DR

This paper presents a methodology combining thermal circuit assembly and state-space extraction to model heat transfer in buildings, validated with real measurements and applicable to building simulation and control.

Contribution

It introduces a novel approach for deriving state-space models from thermal circuits of building components, enhancing accuracy and applicability in building energy analysis.

Findings

Errors within ±1°C for single zone

Errors within ±2°C for seven zones

Validated on real building data over 40 days

Abstract

State-space representation is essential in the theory of dynamic systems. This paper introduces a methodology for obtaining state-space representation from the thermal models of elementary components of a building by the conjunction of two methods: 1) assembling of thermal circuits and 2) state-space extraction from thermal circuit. These methods are fully illustrated on a very simple model and tested on a real house of about 100 m 2 on which detailed measurements were achieved for 40 days at a time step of 10 min. The errors obtained between the measurements and the simulation results are in the order of $\pm$1 {\textdegree}C for a single zone and $\pm$2 {\textdegree}C for seven thermal zones. Besides simulation, parameter identification and control, the methods for assembling thermal circuits and extraction of state-space representation may be useful in Building Information Modelling (BIM).