隨著微機電與微製程技術的進步，微全分析系統已經發展並廣泛應用在藥物治療、醫療診斷、生化分析等應用上。為了要發展高精準度控制的藥物輸送系統，以壓電材料(PZT)為致動器的微型幫浦，其擁有應變時間短、高解析度的形變等驅動特性最適合用來實行在需要高精準控制的系統上面。因此我們需要一個適合的壓電等效電路來作為最佳化前置驅動器的參考資訊使得壓電式微型幫浦在效能上有所提升。在本研究中，將以BVD model為基礎發展出新的壓電等效電路模型，其中包含傳統BVD model與一個串聯的電阻。用此壓電等效電路描述PZT致動器在高電壓、低頻率的方波訊號驅動下所產生的電性反應。另外，透過調整不同輸入方波的電壓與偏壓，將所量測到的實驗數據用來建立相對應的PZT等效電路模型，來說明所新加入的電阻是必要在模擬微幫浦PZT致動器的電性反應上。最後透過常見電路分析軟體SPICE與實驗結果來做比較以驗證此壓電模組的正確性與此方式的可行性。

The field of micro-electro-mechanical systems (MEMs) and microfabrication has produced micro-total-analysis systems (μTAS), which are widely used in medicine, diagnostics, and biological and chemical research. For the development of high precision drug delivery systems, micropumps with a lead zirconate titanate (PZT) actuator, which has a fast response time and high resolution, are most likely to be applied in implementations. To improve the performance of PZT micropumps utilized in the microfluidics field, suitable models are required to enable the optimization of the PZT actuator driving circuits. This study proposes a modified Butterworth-Van Dyke (BVD) model which consists of a BVD model in series with an electrical resistance that describes a PZT actuator driven by a square pulse with a relatively high voltage and low frequency for micropump applications. Experiments were conducted to assess parameters of the model at various voltages; they indicate that the electrical resistance is essential for modeling the PZT actuator of the micropump. The electrical model was verified using a SPICE simulation, whose numerical results were compared with the experimental data for the current response of the PZT actuator. The results show a close correlation between the simulation of the electrical model and the measurements of the PZT actuator under real operating conditions.

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