The main objective of the article is to provide a thorough review of currently used AC-DC converters for alkaline and proton exchange membrane (PEM) electrolyzers in power grid or wind energy conversion systems. Based on the current literature, this article aims at emphasizing the advantages and drawbacks of AC-DC converters mainly based on thyristor rectifier bridges and chopper-rectifiers. The analysis is mainly focused on the current issues for these converters in terms of specific energy consumption, current ripple, reliability, efficiency, and power quality. From this analysis, it is shown that thyristors-based rectifiers are particularly fit for high-power applications but require the use of active and passive filters to enhance the power quality. By comparison, the association combination of the chopper-rectifier can avoid the use of bulky active and passive filters since it can improve power quality. However, the use of a basic chopper (i.e., buck converter) presents several disadvantages from the reliability, energy efficiency, voltage ratio, and current ripple point of view. For this reason, new emerging DC-DC converters must be employed to meet these important issues according to the availability of new power switching devices. Finally, based on the authors’ experience in power conversion for PEM electrolyzers, a discussion is provided regarding the future challenges that must face power electronics for green hydrogen production based on renewable energy sources.

中文翻译：

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适用于电解器应用的AC-DC转换器：最新技术和未来挑战

本文的主要目的是对电网或风能转换系统中用于碱性和质子交换膜（PEM）电解器的当前使用的AC-DC转换器进行全面的回顾。基于现有文献，本文旨在强调主要基于晶闸管整流桥和斩波整流器的AC-DC转换器的优缺点。分析主要集中在这些转换器的当前问题方面，包括单位能耗，电流纹波，可靠性，效率和电能质量。从该分析可以看出，基于晶闸管的整流器特别适合大功率应用，但需要使用有源和无源滤波器来提高功率质量。通过对比，斩波整流器的组合可以避免使用笨重的有源和无源滤波器，因为它可以提高电能质量。然而，从可靠性，能量效率，电压比和电流纹波的角度来看，使用基本斩波器（即降压转换器）存在几个缺点。因此，根据新功率开关设备的可用性，必须采用新兴的DC-DC转换器来解决这些重要问题。最后，基于作者在PEM电解器中进行功率转换的经验，讨论了基于可再生能源的绿色氢生产电力电子必须面对的未来挑战。降压转换器）从可靠性，能效，电压比和电流纹波的角度来看存在几个缺点。因此，根据新功率开关设备的可用性，必须采用新兴的DC-DC转换器来解决这些重要问题。最后，基于作者在PEM电解器中进行功率转换的经验，讨论了基于可再生能源的绿色氢生产电力电子必须面对的未来挑战。降压转换器）从可靠性，能效，电压比和电流纹波的角度来看存在几个缺点。因此，根据新功率开关设备的可用性，必须采用新兴的DC-DC转换器来解决这些重要问题。最后，基于作者在PEM电解器中进行功率转换的经验，讨论了基于可再生能源的绿色氢生产电力电子必须面对的未来挑战。