應用相異控制策略對溫室內噴霧降溫效能影響之探討

The Study on Greenhouse Cooling Effect on Different Control Strategies for Fogging System

李聲謙(Sheng-Chien Lee) ； 張金元(Chin-Yuan Chang) ； 李文汕(Wen-Shann Lee) ； 黃裕益(Yu-I Huang)

《農業機械學刊》 15卷4期 (2006/12) Pp. 23-36

https://doi.org/10.30062/JAM.200612.0003

摘要

本研究利用Matlab軟體建立溫室內動態環境模式，並在不同日射條件下針對不同噴霧降溫控制策略進行模擬。模擬結果顯示，無論是何種控制因子，在良好的策略組合下，皆可使室內溫度下降至低於外界氣溫34.4℃，其下降程度則隨著控制區間與噴霧時間之設定值而變更。在利用相對濕度與時間作為控制因子時，濕度控制區間與噴霧啟動停止時段之選用不當，在高日射量下，會造成室內溫度逆勢上升之現象，而利用溫度做為噴霧啟動條件時，則可有效避免上述之情形。
以不感帶設定控制區間之方式進行噴霧降溫，室內溫度變異主要與區間的設定範圍有關，在可達噴霧停止條件下，範圍愈大，則變異愈大，噴霧系統作動頻率亦愈少；以噴霧時段為控制策略，溫度變異量取決於噴霧時間與間歇時間的長短，欲使間歇噴霧作業所造成的溫度變異量減少，需縮短噴霧總時段，並且減少間歇時間。
本研究以模擬的方式，針對不同噴霧降溫控制策略進行模擬，相關之結果可作為業界在擬定噴霧系統控制策略之參考。

關鍵字

溫室 ； 噴霧系統 ； 控制策略

並列摘要

A dynamic environment model has been established by Matlab software and the greenhouse cooling effect on different control strategies in a fogging system has also been simulated. The simulated results indicated that the indoor temperature could be dropped and lower than the outdoor temperature 34.4℃ under suitable set of control strategy. The degree of dropped temperature changed within limits and delayed time. Inversely, the indoor temperature would raise under a high solar radiation using relative humidity and time delay as control factors. Instead, using temperature control could avoid the above phenomenon.
When using dead zone as control strategy for fogging system, the indoor temperature varied within the upper-lower limit and became large as the on/off frequency of fogging system decreased under a widened range of upper-lower limit.. When the time delay factor was employed in this fogging system, the indoor temperature varied in terms of fogging time and stop time. In order to narrow down the variation of indoor temperature, the operation and stop time in a cycle must be shortened.
In this study, the greenhouse cooling effect results from different control strategies for fogging system has been simulated. The results can be a reference for the control of a fogging cooling system.

並列關鍵字

Greenhouse ； Fogging System ； Control Strategy