可應用於汽車D類音頻放大器之前級整合型升壓轉換器

Integrated Front-End Boost Converter for Automotive Class D Audio Amplifier

賴慶明(Ching-Ming Lai)

車用音頻放大器 ； 電池供電 ； 整合型升壓轉換器 ； 電壓增益改善 ； Automotive audio amplifier ； battery-powered ； integrated boost converter ； improved voltage gain

冷凍空調&能源科技

107期（2018 / 01 / 10）

66 - 71

繁體中文;英文

對於以電池供電之汽車電子裝置，其需要一升壓轉換器進行電壓準位提升。然而，傳統升壓轉換器於高升壓比應用時需要極大之開關工作週期，這導致消耗功率甚鉅以及可靠性較低之問題。為了解決上述之問題，本文提出了一種用於汽車音頻放大器之整合型升壓轉換器。所提轉換器是採用兩相交錯升壓轉換器進一步組接，第一相為升壓轉換器電路，而第二相為反相之升壓轉換器電路。與傳統的兩相交錯升壓轉換器相比，可以實現較高之電壓增益。本文探討轉換器之工作原理，架構分析、模式推導以及閉迴路控制設計。為驗證本文所提可行性，實作一輸入12V（電池）、輸出60V/120W之轉換器原型機並實際應用於車用音響供電系統。經由實驗結果可知，量測波形與模擬結果相符，而轉換器之最大轉換效率可達98.7％，並於滿載情況下效率為89.1%。

High boost DC/DC voltage conversion is always required in a power electronic interface for certain battery-powered electrical devices. However, a conventional boost converter operates with a large duty cycle for such high voltage gain, which results in increased power consumptions and low reliability problems. To solve this issue, a new battery-powered integrated boost converter for automotive audio amplifier is presented. The proposed converter uses an interleaved structure consisting of two phases. In the first phase, a conventional boost converter is employed, and in the second phase, the inverted version of this circuit is used. With this technique, a higher boost voltage gain can be achieved compared with conventional two-phase interleaved boost converters. A derivation of the operating principles of the proposed converter, analyzes of its topology, and the closed-loop control design are performed in this study. Furthermore, simulations and experiments are also performed using a battery input voltage of 12V for a 120W circuit. A reasonable duty cycle is selected to achieve an output voltage of 60V. Finally, the proposed converter is applied with the automotive audio amplifier to verify its feasibility. The measured maximum conversion efficiency of the converter is 98.7%, and the efficiency at full load is 89.1%.

1. Ardi, H.,Ahrabi, R. R.,Ravadanegh, S. N.(2014).Non-isolated bidirectional DC-DC converter analysis and implementation.IET Power Electronics,7(12),3033-3044.
2. Banerjee, S.,Ghosh, A.,Rana, N.(2016).Design and fabrication of closed loop two-phase interleaved boost converter with type-III controller.IEEE Trans. Industrial Electronics,23(6),3331-3336.
3. Lai, C. M.(2014).A battery-powered single-stage three-phase high step-up converter topology for micro DC-UPS.IEICE Electronics Express,11(21),20140852.
4. Wang, J.,Dunford, W. G.,Mauch, K.(1996).A comparison of modified boost converters with continuous inductor current mode and ripple free input current with conventional converters.IEEE Industry Applications Conference
5. Yang, L. S.,Liang, T. J.,Chen, J. F.(2009).Transformerless DC–DC converters with high step-up voltage gain.IEEE Trans. Industrial Electronics,56(8),3144-3152.