The recent interest in flat panel display devices has made a PDP become a promising candidate for the conventional cathode ray tube (CRT) display, because a PDP is praised for its large screen size, wide viewing angle, thinness, long life, and high contrast, etc. But PDP has serious heat problem, because luminance efficiency of AC-PDP is 1.5 lm/W and it is less than 3~5 lm/W of CRT. So there is a need for improving luminance efficiency of AC-PDP. There are several approaches to improve efficiency of PDP. In this paper, increasing frequency of sustaining pulse is used to improve luminance efficiency.
Since the sustain electrodes of a PDP are covered with dielectric and MgO layer, a PDP can be regarded as an equivalent inherent capacitance CP. Therefore a considerable energy of 2CPVS2 for each cycle is dissipated in the non-ideal resistance of circuits and PDP during charging or discharging interval without an ERC. And it is more serious according to increasing frequency of sustaining pulse. In this paper, energy recovery circuit suitable for high frequency driver is introduced. This driver which is operated with current-fed overcomes resonance of parasitic component in panel and driver and fully achieves zero voltage switching of all full-bridge switches.
Experimental results from 200KHz to 700KHz are presented and tested to validate the high frequency driver. Measured luminance efficiency of PDP at high frequency range is 2.5~3 lm/W.
PDP는 대화면화와 광시야각, 높은 명암비등의 장점을 가지고 있기 때문에 CRT를 대체할 차세대 디스플레이 소자로서 각광받고 있다. 하지만 광효율이 1.5lm/W로서 CRT의 3~5lm/W에 비해 낮아 열문제가 심각하다. 따라서 광효율 개선이 현재 PDP의 가장 중요한 문제로 대두되고 있다. 광효율을 개선하기 위해서는 여러가지 접근방식있는데 본 논문에서는 서스테인 주파수를 증가시키는 방법을 사용하였다. 이때 PDP가 용량부하 특성을 가지고 있기 때문에 매 스위칭시 발광에 기여하지 않는 전력소비가 매우크다. 이를 해결하기 위해 에너지 회수회로가 사용되는데 본논문에서는 고주파구동에 적합한 전류주입형 에너지 회수회로를 이용해서 패널전류의 공진현상을 극복하고 200~700KHz의 영역에서 성공적으로 PDP를 구동하였다. 측정된 광효율은 2.5~3 lm/W로서 개선효과를 얻을 수 있었다.
