在中央空調系統中,預測空調負載對於節能是非常重要的一環,若是能預先預測出空調負載,則對於空調主機調度、協調、排程和系統安全性的後續規劃即有明確的目標值可以依循設計規劃。應用人工智慧系統的方法是為了能更有效地得到短期負載預測的結果。人工智慧應用在短期負載預測包含有類神經網路、專家系統及模糊理論。本論文使用模糊理論預測負載,因為模糊理論使用在控制方面,並不需要了解精確的數學模型,它主要是模仿人的經驗控制而不是以控制模型為對象,並可解決數學模式無法精確掌控的系統,但若藉由人工模糊歸屬度的定義,則會造成不夠精準的輸出結果。 為了改善此問題,本論文提出進化規劃法應用於搜尋最佳的歸屬函數,根據過去的天氣狀況及負載,使用最少輸入變數的模式預測空調負載。進化規劃是一種利用多點搜尋的最佳化演算法,所以較能避免落入局部最佳解中,其不但省去了基因演算法的編碼程序,並只藉突變搜尋全域最佳解,因此能比基因演算法計算時間更為縮短,以更快速度獲得全域最佳解。為了驗證其有效性,本論文使用的測試資料是以新竹某半導體廠實際資料作為應用實例,並和傳統模糊預測作比較。預測所得的結果顯示本法均比傳統模糊預測更為精準,非常適合空調系統實際操作上的應用。
In the air-conditioning system, Load Forecasting on HVAC is a key factor for energy saving. If the Load Forecasting on HVAC is possible, there will be a distinct target value as ground for further programming on Dispatch, Coordination, Schedule and System Security of chiller. The reason why applying artificial intelligence system is to get short-term load forecasting result more effectively. Artificial intelligence systems which can be applied on short-term load forecasting includes neural network, expert systems and fuzzy theory. Fuzzy theory is adopted in this study because it’s not necessary for researchers to understand accurate mathematical models. Fuzzy theory mainly simulates human control experience rather than control models. It can also deal with systems which can not be precisely controlled by mathematical models. However, defining fuzzy theory through artificial fuzzy membership functions results in inaccurate outputs. In order to solve the problem, Evolutionary Programming (EP) is brought up in this study for searching optimal membership functions, using the model with fewest variables input to forecast load of HVAC, based on past weather statuses and loads. EP is a multi-point researching optimal algorithm, freer from local optimal. Leaving out the encoding process of Genetic algorithm and searching global optimal through mutations only, EP calculates faster than Genetic algorithm and gets global optimal in a shorter time. To examine the effectiveness, real data from a semiconductor plant in Hsin-chu is used as test material and studying case in this study, and is comparing it to Fuzzy load forecasting method. The forecasting result shows that this method is more accurate than Fuzzy load forecasting method, and suitable for applying on real-world operation of air-conditioning