Summary
The determination of the desired values of climate factors is important for achieving control environment of greenhouse.HomePage
Investigations about semi-forcing culture of tomato were made for 20 farmers in NIIGATA prefecture. With the results of investigations, such as yield, cost of heating, quality of fruit, growing stage, weather and horticultural experience etc., the optimal set-point were realized by fuzzy interface. Besides this, to reduce the consumption of energy and also to improve the response characteristics of control system, the climate control experimants in the model house were carried out using fuzzy theory. The threshold for set-points can be made change according to the rate of change of temperature and humidity, the properties of this control system were examined. In comparison to this control, the general ON/OFF control experiments were also made.
As the result, for the temperature control, the errors of fuzzy control is less than that the ON/OFF control. For the ventilation control, the control error is less than the ON/OFF control. For the sophisticated control of temperature and humidity, there is no difference between fuzzy control and ON/OFF control for temperature, but for humidity the overshoot and control error are restrained as low level for the fuzzy control.Keywords: greenhouse, environmental control, tomato cultivation, climate set-points, ON/OFF control, fuzzy control