State estimation concept for a nonlinear melting/solidification problem of a latent heat thermal energy storage

Effective estimation of the state-of-charge of latent heat thermal energy storage for heating and cooling systems using non-linear state observers

“…To the best of the authors' knowledge, the use of state observers to estimate the SoC of an LHTES unit which considers the whole temperature range of the storage medium within the unit is restricted to [35,43]. Despite their good accuracy, these observers are based on extended Kalman filters, which involve a highly complex design process.…”

“…The approach employs a simple non-linear observer to accurately estimate the temperatures of the PCM and the HTF. As the observer is based on a 1-D spatially discretised model of the thermal store defined by a set of ODEs, this has a significantly simpler structure than the observer models reported in [35,43], which are based on 2-D models.…”