本論文提出一應用於LED驅動電路系統之鐵磁諧振變壓器，以提高LED驅動電路系統的交流穩壓率及高頻訊號衰減能力。
LED路燈裝設於戶外環境時，因其高頻LED驅動電路的高頻隔離變壓器，無法有效抑制突波電流而致使LED路燈損壞。因此，本論文擬提出一低頻鐵磁諧振變壓器，代替高頻變壓器以更有效地保護LED路燈電路系統。由於低頻鐵磁諧振變壓器圈數較高頻隔離變壓器多，故其漏感與寄生電容較高頻隔離變壓器大。因此，當突波發生時，低頻鐵磁諧振變壓器可更有效地旁路突波電流與遏阻突波電流。此外，當變壓器之輸入電壓超過額定電壓時，因一次側線圈所產生之磁通量，部分經由磁分路回流至一次側線圈，形成磁旁路，此時二次測線圈的耦合磁通量可保持不變，俾以達到交流穩壓功能，使LED路燈電路不受供電系統的過電壓而損壞LED路燈。
本論文將設計與製作鐵磁諧振變壓器及升-降壓型LED驅動電路之雛型件與雛型電路，俾以進行具鐵磁諧振變壓器之LED路燈系統總成測試，驗證其對高頻訊號的衰減及交流穩壓能力。

This thesis presents the design and implementation of the ferroresonant transformer for the LED driver systems to achieve the high-frequency noise attenuation and AC line voltage regulation.
The high-frequency transformer used in the LED driver system for the outdoor LED street lamps cannot effectively suppress the surge current to avoid the damage on the LED street lamps. However, the low-frequency transformer can be applied to protect the LED street lamps from the surge current instead of the high-frequency transformer.
The turns numbers of the low-frequency transformer, which are much more than those of high-frequency transformers, provide larger leakage inductances and parasitic capacitances to effectively suppress and shunt the surge current, respectively. In addition, the low-frequency ferroresonant transformer can be proposed to avoid the over line voltage to damage the LED street lamps instead of the low-frequency conventional transformer. When the input voltage is higher than the rated voltage, certain part of the magnetic flux generated from the primary-side winding flows through the magnetic shunt but not the secondary-side winding. Meanwhile, the rated output voltage of the secondary side can be remained to achieve the AC line voltage regulation.
A prototype of the low-frequency ferroresonant transformer is designed and implemented to verify the feasibility of the high-frequency noise attenuation and AC line voltage regulation for the proposed LED driver systems.

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