Real-time state observer design for solar thermal heating systems

Nowadays it is important to investigate and develop solar thermal heating systems as an environmental friendly technology. In the paper we demonstrate a physically-based linear mathematical model that can be applied to a wide range of solar heating systems to analyze and develop them.We construct a Luenberger type state observer for the mathematical model, which enables us to estimate in real-time the unmeasured state variables of the solar heating system. We give a general algorithm for the practical application of the estimation process.Comparing calculations and measurements, we introduce the usability of the state observer in case of a particular solar heating system that produces domestic hot water at the campus of the Szent István University, Hungary.