A model for the climate of an innovative closed greenhouse for model based control

A new greenhouse type is designed to study ways of decreasing horticultural water use in semi-arid regions. To control the greenhouse a model based control design will be applied. Hereto a model is needed to predict the systems behavior (1 day ahead), without much computational effort. A physics-based model for this new type of greenhouse is developed, based on enthalpy and mass balances. The greenhouse is divided in four compartments; the plant area, the roof area, the heat exchanger and the soil. For all compartments only the main energy and mass fluxes are modeled, in order to keep the model simple. Since the model describes only the main characteristics of the system with physical equations, careful calibration and validation (systems identification) is needed. Real data gained from the experimental greenhouse are used in a controlled random search to find the optimal parameter values.