On-line Estimation of the Ventilation Rate of Greenhouses

Authors:	Bontsema Jan, Agrotechnology & Food Innovations B.V., Netherlands van Henten Eldert, Agrotechnology & Food Innovations B.V., Netherlands Kornet Jan, Agrotechnology & Food Innovations B.V., Netherlands Budding Jorrit, Priva B.V., Netherlands Rieswijk Theo, Priva B.V., Netherlands
Topic:	8.1 Control in Agriculture
Session:	Control for Agricultural Facilities
Keywords:	greenhouse climate, observer, ventilation rate, unknown input observer

Abstract

Using an unknown input observer, with an output linearising feedback, an on-line estimator for the ventilation flow or rate is developed for natural ventilated greenhouses. The paper shows how to design, implement and tune such an estimator in practice and shows that it performs well. Furthermore the practical value for the grower is discussed.