應用非對稱半橋LCC諧振換流器於外部電極螢光燈管之照明用電子安定器

Applying Asymmetrical Half-Bridge LCC Resonant Inverter to EEFL Lighting Ballast

陳國揚(Kuo-Yang Chen)

指導教授 ： 胡國英

國立臺北科技大學/電資學院/電力電子產業研發碩士專班/碩士(2010年)

摘要

於本論文中，以非對稱半橋LCC諧振換流器為外部電極螢光燈管照明用電子安定器之核心。整體架構共使用三級轉換器。第一級為轉移模式(Transition Mode, TM)功率因數修正電路，輸入為全範圍電壓，此功率修正電路為昇壓型轉換器，可將電壓升壓至390Vdc。第二級為降壓型轉換器，係採用PWM控制IC來調控責任週期以改變輸出電壓，以達到調光的目的。第三級為非對稱半橋LCC諧振換流器，藉由LCC諧振，使得換流器操作於零電壓切換，，以減少功率開關上的切換損失，並同時藉由其高電壓增益特性，使其輸出增益大於1，可以降低變壓器之圈數比。
就模擬而言，使用IsSpice模擬軟體，將變壓器一二次側漏感與寄生電容加入諧振電路一同參與諧振，藉由實際繞製變壓器所得之參數進行模擬，模擬結果必須能符合切換開關上之零電壓切換且高電壓增益之要求。就實作而言，將繞製完成之變壓器，實作一非對稱半橋LCC諧振換流器，將測量波形與模擬波形相互驗證。就理論分析而言，將非對稱半橋LCC諧振隔離架構等效為非隔離架構，並求得其轉移函數，藉由此轉移函數可得知諧振元件參數與切換頻率對電壓增益的影響。就應用而言，將實作一具有多支EEFL並聯之燈箱，並將所設計之換流器來驅動此燈箱。

關鍵字

非對稱半橋 ； LCC諧振換流器 ； 功率因數修正器 ； 外部電極螢光燈管 ； 電子安定器 ； 調光

並列摘要

In this thesis, an asymmetric half-bridge LCC resonant inverter is presented, which is the kernel of the proposed lighting ballast that is used to drive the an external electronic fluorescent lamp (EEFL). Such a lighting ballast contains three power stages. The first power stage is constructed by a boost converter with power factor correction (PFC), and such a the converter is operated in the transient mode (TM) with the DC output voltage 390V. The second power stage is built up by a buck converter which uses a pulse-width-modulation (PWM) control integrated circuit (IC) to control the duty cycle such that the corresponding output voltage can be changed and hence dimming of the EEFL can be achieved. The third power stage is established by an asymmetric half-bridge LCC resonant inverter. Via LCC resonant, the power switches of this inverter are operated in zero voltage switching (ZVS) to reduce the switching loss, and at the same time, the inherent high voltage conversion characteristics make the voltage conversion gain be high than one such that the turn ratio of transformer can be reduced.
In this paper, only the third stage is simulated based on IsSpice. Via the primary and secondary leakage inductances of the transformer along with one external series capacitance, the LCC resonant are simulated under open-loop control. The simulated results must guarantee to the power switches with ZVS turn-on and the high voltage conversion gain. After this, one asymmetric half-bridge LCC resonant inverter is carried out based on the designed transformer. Accordingly, the measured and simulated results are verified alternately. Furthermore, this inverter is reduced to an equivalent non-isolated circuit, and hence the corresponding transfer function can be obtained. Based on such a transfer function, the effect of resonant parameters and switching frequency on the voltage gain can be known. Finally, the inverter, together with the other two power stages, is used to drive and dim EEFL.

並列關鍵字

Asymmetrical Half-Bridge ； LCC Resonant Inverter ； PFC ； EEFL ； Ballast ； Dimming

參考文獻

[11] 彪千科技股份有限公司，http://www.toccfl.com/

[44] 陳以尚，單級非對稱半橋可調光電子安定器，私立中原大學電機工程學系碩士學位論文，2004。

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