多變數強韌控制理論在質子交換膜燃料電池上的應用

Multivariable Robust Control of a Proton Exchange Membrane Fuel Cell System

陳炫綜(Hsuan-Tsung Chen)

指導教授 ： 顏家鈺

共同指導教授 ： 王富正

國立臺灣大學/工學院/機械工程學研究所/博士(2009年)

https://doi.org/10.6342/NTU.2009.10465

摘要

本文係利用強韌控制理論-中央控制與定階強韌控制理論於質子交換膜燃料電池，進行控制器設計，以達到穩定輸出電壓以及降低氫氣消耗的目標，最後將強韌控制器以單晶片系統實現，以控制質子交換膜燃料電池。由系統的觀點來看，燃料電池本身可視為一雙輸入雙輸出的系統，其輸入為空氣與氫氣的流量，輸出為電壓與電流，若是固定輸出負載，則此系統可進一步簡化為雙輸入單輸出的系統，因此我們可藉由控制空氣與氫氣的流量，來控制電壓或電流的輸出量，因為一般的電器用品或是DC/DC轉換器大都需要穩定的電壓供應，因此在本文中以穩定輸出電壓為目標。由於燃料電池本身為非線性且時變的系統，因此本文應用系統識別方法，在各操作點將質子交換膜燃料電池識別為多變數線性系統，而將系統之非模化動態，視為系統不確定性與外部干擾，並利用強韌控制來達到穩定系統與增進效能的目標。我們更進一步針對一般的強韌控制具有階數較高（系統階數加上權重函數的階數）的缺點，引入定階強韌控制理論，希望以較低階的控制器達到預計的設計要求。最後，則是將所設計的多變數強韌控制器實現於單晶片系統上，成功完成系統的縮小化與可攜式的目標。最後實驗結果顯示，所設計之多變數控制器，確實能達到系統穩定、增進性能與系統縮小化的目標。

關鍵字

質子交換膜燃料電池 ； 強韌控制 ； 系統識別 ； 定階控制設計 ； 氫氣使用效率 ； 單晶片控制器實現

並列摘要

This paper applies multivariable robust control strategies-central control and fixed-order control to a proton exchange membrane fuel cell (PEMFC) system and implements the designed controllers on a microchip for system miniaturization. From the system point of view, a PEMFC can be modeled as a two-input-two-output system, where the inputs are air and hydrogen flow rates and the outputs are cell voltage and current. By fixing the output resistance, the system can be further reduced to a two-input-single-output system. That is, we can either control the cell voltage or current output by regulating the air and the hydrogen flow rates. Since most electrical equipment requires constant voltage supply, in this thesis we aim to control the cell voltage output. Due to the nonlinear characteristics of this system, multivariable robust controllers were designed to provide robust performance and to reduce the hydrogen consumption of this system. However, for standard robust control design, the order of resulting controllers is constrained by the plants and weighting functions. For hardware implementation, controllers with lower orders are preferable in terms of computing efforts and cost. Therefore, we apply fixed-order robust control algorithms to design controllers with specified orders for a PEMFC, and evaluate efficiency of the system employing these controllers. Furthermore, the designed controllers are implemented on a microchip for system miniaturization. From the experimental results, multivariable robust control is deemed effective in supplying steady power and reducing fuel consumption.

並列關鍵字

Proton Exchange Membrane Fuel Cell ； Robust control ； System identification ； Fixed-order optimization ； Hydrogen efficiency ； System implementation

參考文獻

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