The design demands for compact and low-profile power supplies are rapidly growing due to the preference for smaller and thinner appearance of industrial and consumer electronics. In this study, practical design methods for a high-density and low-profile DC-to-DC power converter are proposed. The prototype board of a 24 V/20 A LLC resonant converter was implemented. Given that a half-bridge circuit on the primary side operated with zero-voltage switching, the nominal operating frequency was further increased to 300 kHz. Notably, when an LLC series resonant converter with a low output voltage and high load current operates at a high switching frequency, several practical design considerations are required. A synchronous rectifier on the secondary side was configured to reduce the conduction losses. Gallium nitride-based transistors with high- and medium-voltage ratings were applied to the input and output sides due to their superior switching properties. A multi-layered PCB substrate was introduced to facilitate the design of the devices. Finite-element analysis of the PCB layout and thermal design was empirically conducted through computer simulation techniques. The parallelly connected gallium nitride-based transistors achieved a reliable operation and superior performance. Through a magnetic analysis, the design of a low-profile integrated transformer was optimized for high-frequency operation. Regarded as the most critical issue in gallium nitride-based transistors operating at high frequencies, the performance in electromagnetic interference was verified through effective measurements of conducted and radiated noises.

由于工业和消费电子产品更小、更薄的外观，对紧凑和薄型电源的设计需求正在迅速增长。在这项研究中，提出了一种高密度和薄型 DC-DC 电源转换器的实用设计方法。实现了 24 V/20 A LLC 谐振转换器的原型板。鉴于初级侧的半桥电路以零电压开关运行，标称工作频率进一步提高到 300 kHz。值得注意的是，当具有低输出电压和高负载电流的 LLC 串联谐振转换器在高开关频率下工作时，需要几个实际的设计考虑因素。次级侧的同步整流器被配置为减少传导损耗。具有高和中压额定值的氮化镓基晶体管由于其卓越的开关特性被应用于输入和输出侧。引入了多层 PCB 基板以促进器件的设计。PCB布局和热设计的有限元分析是通过计算机模拟技术经验性地进行的。并联的氮化镓基晶体管实现了可靠的操作和卓越的性能。通过磁性分析，针对高频操作优化了薄型集成变压器的设计。作为在高频下工作的氮化镓基晶体管中最关键的问题，电磁干扰的性能通过有效测量传导和辐射噪声得到验证。