以VRFT方法設計PEMFC電力系統之整合控制

Design of Coordinating Control for a PEMFC Power System Based on VRFT Method

葉真旭(Chen-Hsu Yeh)

指導教授 ： 鄭智成

國立臺北科技大學/工程學院/化學工程研究所/碩士(2013年)

摘要

在包含燃料重組器與電流轉換器的質子交換膜燃料電池電力系統中，子系統的動態特性會明顯影響到整個系統追蹤負載需求的性能。此外，部分程序参數例如燃料使用率等，若超過其特定範圍則對燃料電池造成很大的損傷，因此整合該電力系統之控制以及防止程序参數違反限制有其必要性。本研究針對燃料電池電力系統中燃料重組器以及電流轉換器之整合控制進行研究。由於此電力系統具有高度非線性動態，系統模式識別困難且容易產生模式誤差，本研究以虛擬參考回饋調諧方法為基礎，直接以系統操作資料來設計控制器，可以免去非線性模式的識別誤差。考慮到系統的非線性動態，提出適應性虛擬參考回饋調諧方法，線上更新用於控制器設計之製程資料，此外，對於電流轉換器之控制器設計，其虛擬參考回饋調諧參考模式中的設計參數則根據燃料使用率的偏差來線上調整，使電流轉換器的動態特性隨時與燃料重組器的動態特性一致，達到整合控制之目的。最後以串級控制的架構來應付燃料電池電力系統之負載需求變化。模擬結果顯示此整合控制設計可使燃料電池電力系統在追蹤負載需求的同時，也能維持穩定的燃料使用率。

關鍵字

虛擬參考回饋調諧 ； 整合控制 ； 質子交換膜燃料電池

並列摘要

For a Proton Exchange Membrane Fuel Cell (PEMFC) power system with a fuel reformer and a DC-DC converter, the dynamic properties of the subsystems strongly affect the performance of PEMFC for tracking load demands. In addition, violation of several process parameter constraints (e.g., fuel utilization) can permanently damage the PEMFC system. Thus, coordinating the controllers of the PEMFC power system and preventing constraint violation are necessary. This study investigates the coordinating control between the fuel reformer and the DC-DC converter in a PEMFC power system. Because the system has considerable nonlinear behavior, model identification is difficult and modeling error is inevitable. This study uses the virtual reference feedback tuning (VRFT) method which designs the controllers directly from a set of system operating data without resorting to a process model. Considering the nonlinearity of the PEMFC power system, an adaptive VRFT method is proposed, where system input-output data for controller design are on-line updated at each sampling time. At the same time, the parameter in the VRFT reference model for DC-DC converter is also on-line updated according the deviation of fuel utilization. In this manner, the converter dynamics is consistent with the dynamics of the fuel reformer, resulting in a coordinating control scheme in a PEMFC power system. In addition, a cascade control structure is used to cope with the variation in power load. Simulation results show that the proposed coordinating control scheme can efficiently track the power load demands and also maintain the fuel utilization constant.

並列關鍵字

Virtual reference feedback tuning ； Coordinating control ； Proton exchange membrane fuel cell ； Addptive control

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