Efficient Gallium Nitride-Based AC-DC Power Conversion Circuits for Information Technology, Electric Transportation and Industrial Applications

消费和工业应用，包括计算机、电动汽车、信息技术服务器和工业电池供电设备，广泛使用电能。电能必须从交流(AC)实用电压(例如120 V)转换为直流(DC)电压(例如48 V和400 V)才能为这些应用供电。这种电压转换使用了高开关频率(例如几十到几百千赫)的AC-DC整流电路。许多转换器组件的尺寸与开关频率成比例减小，因此需要提高开关频率。问题是，电路中的损耗往往与开关频率成比例地增加，这使得AC-DC功率转换电路在较高的开关频率下固有地效率较低。因此，需要新的技术来实现更高的开关频率，同时降低损耗。使用兆赫开关频率的氮化镓开关用于消费和工业千瓦AC-DC整流器的新技术在以下方面进行了分析和实验评估：*i)非隔离无桥功率因数校正电路，以降低开关和导通损耗。*ii)隔离DC-DC功率转换器电路，以提高第二级隔离DC-DC转换器的效率。*iii)隔离单级功率因数校正电路，以降低开关和导通损耗。*本研究计划的长期目标是开发新技术，以提高开关和导通损耗千瓦功率级AC-DC整流器的功率转换效率。拟议计划中开发的技术将广泛用于未来一代消费和工业产品，从信息技术服务器电源到工业和电动汽车电池充电器。预计这项研究计划中提出的技术将使电力转换效率提高至少3个百分点，从而减少为这些产品提供电力所需的发电量，并相应减少温室气体排放。

Consumer and industrial applications, including computers, electric vehicles, information technology servers and industrial battery powered devices make extensive use of electrical energy. The electrical energy must be converted from the alternating current (AC) utility voltage (e.g. 120 V) to a direct current (DC) voltage (e.g. 48 V and 400 V) to power these applications. High switching frequency (e.g. tens to hundreds of kilohertz) AC-DC rectifier circuits are used for this voltage conversion. The size of many of the converter components reduces proportionately to the switching frequency, so increased switching frequencies are desired. The problem is that losses in the circuits tend to increases proportionally to switching frequency, making the AC-DC power conversion circuits, inherently less efficient at higher switching frequencies. Therefore, new technologies are required to enable higher switching frequencies while reducing losses.******The objectives of the proposed research program include invention, analysis and experimental evaluation of novel technologies for consumer and industrial kilowatt power AC-to-DC rectifiers using gallium nitride switches at megahertz switching frequencies in the following areas:***i) Non-isolated bridgeless power factor correction circuits to reduce switching and conduction losses.***ii) Isolated DC-DC power converter circuits to improve the efficiency of second-stage isolated DC-DC converters.***iii) Isolated single-stage power factor correction circuits to reduce switching and conduction losses.******The long-term objective of this research program is to develop novel technologies to increase the power conversion efficiency for kilowatt power level AC-DC rectifiers. The technologies developed in the proposed program will be used in a wide range of future generation consumer and industrial products, ranging from information technology server power supplies to industrial and electric vehicle battery chargers. It is expected that the technologies to be proposed in this research program will enable power conversion efficiency improvements of at least three percentage points, resulting in a reduction in the energy generation required to provide power to these products and a corresponding reduction in greenhouse gas emissions.