In inverter-based microgrids, individual inverters operate usually with their own digital processor. The clocks used to generate the time signals of these processors differ from each other due to clock drifts. This paper analyzes the impact that the drifts of the processors clocks produce on the operation of inverter-based islanded microgrids. Several communication-free secondary control schemes, which avoid well-known problems caused by digital communication networks, are considered. Active power sharing and frequency regulation are the metrics used to evaluate the performance of the control schemes. The study reveals advantages, drawbacks, and practical limitations of the control schemes caused by the clocks drifts. Therefore, it facilitates the selection of the most suitable control scheme for the practical deployment of microgrids. The theoretical results are validated by experimental tests in a laboratory microgrid equipped with three inverters and three digital signal processors driven by autonomous internal clocks.

中文翻译：

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时钟漂移对基于逆变器的孤岛微电网的无通信二次控制方案的影响


在基于逆变器的微电网中，各个逆变器通常使用自己的数字处理器运行。由于时钟漂移，用于生成这些处理器的时间信号的时钟彼此不同。本文分析了处理器时钟漂移对基于逆变器的孤岛微电网运行产生的影响。考虑了几种免通信的二次控制方案，避免了数字通信网络引起的众所周知的问题。有功功率共享和频率调节是用于评估控制方案性能的指标。该研究揭示了由时钟漂移引起的控制方案的优点、缺点和实际限制。因此，有利于为微电网的实际部署选择最合适的控制方案。理论结果通过实验室微电网中的实验测试得到验证，该微电网配备了三个逆变器和三个由自主内部时钟驱动的数字信号处理器。