應用基因規劃法於冰水主機負載分配之最佳化

Optimal Chiller Loading Using Genetic Programming

魏仁杰(Ren-Jie Wei)

指導教授 ： 張永宗

國立臺北科技大學/機電學院/能源與冷凍空調工程系碩士班/碩士(2007年)

https://doi.org/10.6841/NTUT.2007.00092

摘要

本研究採用生物進化型態之演算法－基因規劃法，來執行冰水主機耗電模型之建立，及實現冰水主機負載分配之耗電最佳化。在建立冰水主機耗電之模型時，需先紀錄主要影響耗電量之各種參數值，此參數值分別為冰水主機之冰水出水溫度、冷卻水入水溫度以及冷凍容量。利用此三參數作為基因規劃法之終點端，再利用數學符號作為基因規劃法之函數端，以實際之冰水主機耗電量作為目標，利用基因規劃法之運算子作迭代運算，最終可得到足以說明此三參數與冰水主機耗電量之關係函數，即為冰水主機耗電模型。
中央空調系統之耗電量與冰水主機運轉效率之高低關係密切，若能在滿足負載需求下使每部冰水主機依其特性曲線運轉於最佳點，則將消耗最少電力，此即OCL（Optimal Chiller Loading）。目前冰水主機的負載分配法有平均負載法、拉格蘭傑法，這些方法皆有其缺點。例如平均負載法並不是最佳運轉點、拉格蘭傑法λ值初值設定不當會有發散的問題。本文以二次多項式來表示冰水主機之kW-PLR特性曲線，並以系統總耗電量為目標函數，並符合限制條件與滿足系統負載所需，採用基因規劃法來執行冰水主機負載分配最佳化，使系統之耗電量為最小。

關鍵字

基因規劃法 ； 回歸方程式 ； 平均負載分配法 ； 主機最佳負載分配 ； 拉格蘭傑乘數法

並列摘要

This study used a algorithm which about creature evolution - Genetic Program. To analyze the consumption energy model of chiller, and to compute the optimal load sharing for multiple chillers by using this algorithm. Must to record the dates which would effect the consumption energy of chiller before to construct the chiller model. The dates include the chiller water supply temperature、cooling water return temperature and refrigeration ton. Finally, taking these dates and using it as the functions of genetic program (GP), and using the standard arithmetic operation as the terminals of GP. The object in this algorithm is the chiller consumption energy. Through the option of GP which contains ‘crossover’、 ‘reproduce’ and ‘mutation’ to iterant compute the population is composed of functions and the terminals of GP. Finally, we would find the consumption energy model of chiller.
The consumption energy for central system is relate to the operating efficiency of multiple chillers. The purpose of the Optimal Chiller Loading (OCL) is to meet the system load and to decide the chillers’ optimal part load ratios (PLR) to reduce the system power consumption. The optimal chiller loading methods include Average Loading (AVL) method and Largrangian Multiplier (LGM) method These methods have some shortcomings. Such as AVL method being not optimal. LGM method will diverge if the initial condition isn’t suitable. This thesis uses a square equation to simulate the chiller’s kw-plr curve and to find a set of chiller output which doesn’t violate the operating limits while minimizing the objective function. The GP is adopted to find the near optimal solution of the function.

並列關鍵字

Genetic Program ； Regression Equation ； Average Loading ； Optimal Chiller Loading ； Lagrangian Multiplier Method

參考文獻

[14]許聰海，積木型遺傳規劃法於最佳化組合之應用，碩士論文，台北科技大學，2003。

[15]江建樺，應用模擬退火演算法於冰水主機負載分配之最佳化，碩士論文，台北科技大學，2005。

[6]J.E. Braun, Methodologies for the Design and Control of Central of Cooling Plants, Ph.D. Dissertation, University of Wisconsin, 1988.

[16]陳建進，應用進化策略演算法於冰水主機負載分配之最佳化，碩士論文，台北科技大學，2006。

[19]林進煌，變頻冷卻水塔之節能研究，台北科技大學，碩士論文，2005。