電容切換式磷酸鋰鐵電池串聯平衡均充電路之研製

本論文旨在研製電容切換式磷酸鋰鐵電池串聯平衡均充電路，前級採用定電流-定電壓充電控制法控制直流/直流降壓型截波器，作為蓄電池充電控制之用。並利用電容作為電池能量轉移元件，透過切換開關將串聯電池組內的電池電量平衡，以達到均勻充電及電池電能平衡之目的。本文首先繪出磷酸鋰鐵電池的充、放電特性曲線後，建立磷酸鋰鐵電池之等效電路模型，採用Powersim (Psim)套裝軟體模擬模組式電容切換式電池平衡電路，並利用降壓型截波器配合定電流-定電壓二段式控制法則，完成磷酸鋰鐵電池串聯與模組式平衡均充電路之模擬，作為系統設計及數位控制之依據。本文以數位信號處理器(dspic33FJ16GS504)為系統控制核心，完成8顆10Ah磷酸鋰鐵電池模組式串聯平衡均充電路之雛型，並完成測試，以驗證理論之正確。

關鍵字

電池平衡；平衡充電；降壓型截波器

並列摘要

This thesis is concerned with the development of a switching capacitance LiFePO4 battery balance charging circuit in series structure. A constant-current constant-voltage charging method was adopted to control the DC/DC buck chopper for battery charging. The capacitance was used as the energy transfer components, and combining the switching devices to achieve the battery balance and charging equalize. First the charging and discharging curves of the LiFePO4 battery cell was plotted and equivalence circuit model was established. The Psim package software was adopted to simulate a module type switching capacitance LiFePO4 battery series balance circuit. The constant-current and constant-voltage two-stage control strategy was used to control the DC/DC buck chopper to simulate the LiFePO4 battery series and module type balance charging equalize circuit for system design and digital control. A digital signal processor (dspic33FJ16GS504) was applied to implement eight LiFePO4 module type switching capacitance battery series balance charging circuit. Experiment was then conducted to verify the theory.