Triboelectric nanogenerator (TENG) is considered as a potential solution to harvest distributed energy for the sustainable and reliable power supply of the internet of things. Although numerous researches on alternating current (AC) output TENG from fundamental physics to potential applications have been widely promoted in recent years, the studies about direct current (DC) output TENG is just beginning, especially for a constant current output. This work gives the summary of recent key researches from AC-TENG to DC-TENG, especially a constant current TENG, as well as the design of AC/DC-TENG. In addition, some new DC generators will also be summarized toward a wide range of readers. This study presents the similarities and differences between AC-TENG and DC-TENG, so that their impact and uniqueness can be clearly understood. Finally, the major challenges and the future outlooks in this rapidly emerging research field will be discussed as a guideline for future research.

摩擦电纳米发电机（TENG）被认为是一种收集分布式能源的潜在解决方案，可为物联网提供可持续和可靠的电力供应。尽管近年来对从基础物理学到潜在应用的交流（AC）输出TENG进行了大量研究，但有关直流（DC）输出TENG的研究才刚刚开始，特别是对于恒定电流输出。这项工作总结了从AC-TENG到DC-TENG的最新关键研究，尤其是恒定电流TENG，以及AC / DC-TENG的设计。此外，还将针对一些读者总结一些新型的直流发电机。这项研究提出了AC-TENG和DC-TENG之间的异同，因此可以清楚地了解它们的影响和独特性。最后，