單級柔切式交/直流轉換器及其在複金屬燈電子安定器的應用

Abstract

高強度氣體放電燈之一的複金屬燈具有高演色性、高效率、長壽命等優點；然而它也有點燈暫態時間長、點燈電壓極高、音頻共振等問題。 本論文提出一完整的複金屬燈電子安定器設計方法，其架構包括下列三個部分：(i)以單級交/直流轉換器的架構取代功率因數校正電路以及直流/直流轉換器兩個架構，來達成功率因數校正、直流/直流穩壓等功能，以達成電路精簡的目的。(ii)主動箝位電路的加入，可將儲存在變壓器漏感上的能量回送至電源側再利用，有效的抑止了開關電壓應力且使開關達到零電壓切換、降低切換損失，提高轉換器效率。(iii)避免音頻共振的全橋式低頻方波換流器。實做驗證方面，實做出一150 W的複金屬燈電子安定器，並使用一簡單的最大電流限制及功率控制方法來保護電子安定器以及複金屬燈，不因為過功率而損壞。

Metal-Halide Lamp is one of the High-Intensity-Discharge Lamps. It has stronger advantages in color rendering, lighting efficiency, and lifetime. However, some problems must be solved for designing the ballast of the HID lamp, those are long preheating time, extremely high starting ignition voltage, and acoustic resonance. This thesis proposes a complete design of the electronic ballast for Metal-Halide Lamps. Include three parts: (i) using a single-stage high power factor AC/DC converter in stead of the general two stage topology, in order to simplify the topology, (ii) using the active clamp circuit can recycle the energy trapped in the leakage inductance of the transformer (to keep the switch voltage stress low) and achieve soft switching to reduce the power dissipation to attain high efficiency, (iii) using a full-bridge square wave inverter to avoid the acoustic resonance. The upper current limit and constant power control are designed to protect the Metal-Halide Lamp from burning out.