高耐圧GaN－HEMTの無電極ランプ照明回路への応用

摘要

This paper reports the demonstration of the resonant inverter circuit for electrodeless fluorescent lamps using a high-voltage GaN-HEMT as a main switching device. A 620-V/l .4-A GaN-HEMT was designed and fabricated for power electronic applications. The dynamic on-resistance increased with current collapse phenomena was suppressed by the dual-FP structure and the switching operation could be realized under high applied voltage of over 350 V. As a high-voltage and high-frequency power supply application, a 13.56-MHz resonant inverter circuit for electrodeless fluorescent lamps was demonstrated using the fabricated device. The demonstrated circuit achieved high-voltage operation of 380 V, high-speed gate-switching of 4.5-7 ns, and lighting of the electrodeless lamp with an input power of 7-10 W. High-voltage operation realized a simple circuit composition for high-power efficiency and the discharge ignition of the lamp without the starting circuit. The power efficiency of the inverter circuit was over 90% with an input power of 9 W. These results show that high-voltage GaN devices are suitable for high-frequency switching applications under high-input voltages of several hundred volts.%高耐圧GaN-HEMTを用いた共振インバータ回路による無電極ランプ照明回路を検証した結果について報告する。電流コラプスによるオン抵抗増加を抑制するDual-FP構造を採用した620V／1．4AGaN-HEMTを試作し、350V以上の高電圧スイッチングを実現した。高電圧・高周波電源応用として、試作した素子を主スイッチング素子に用いた13．56MHz共振インバータ回路によって無電極ランプ照明回路を動作させた。ピーク電圧380V、ゲートスイッチング時間4．5-7ns、入力電力7-10Wの状態にてランプ点灯を確認し、効率は90％以上と見積られた。これらの結果から、高耐圧GaNデバイスの高電圧（数百Ⅴ）・高周波応用の可能性が示された。