基于改进正交理论的电网谐波电流检测算法及其应用

摘要

随着新能源分布式发电技术的发展，以微电网为代表的新型电网系统得到越来越多学者的关注。微电网中连接不同系统之间需要各种类型的电力电子设备，这将大量谐波电流引入到微电网系统中，对继电保护系统造成了一定的影响，引起系统稳定性下降等问题。因此针对微电网继电保护系统的谐波电流检测方法是研究热点之一。针对此类问题，根据改进正交理论，提出了一种改进正交分次谐波电流检测算法，相比其他的谐波电流检测方法，提出的算法物理意义清晰明确，运算简单、快速、准确。对提出的方法进行了理论分析介绍，仿真计算和实验结果验证了所提出方法的可行性。最后以电流保护为例，给出利用该算法的微电网继电保护系统谐波治理的方法。%With the development of the renewable distributed power generation technology , new types of grid system is attracting more and more attentions such as micro grid.Various kinds of power electronics equipments are needed in the connections between different systems , which will introduce lots of harmonic currents into the micro grid system and may decrease the stability of the system .So the detection method of harmonic current is one of the hottest topics in such field.A novel improved quadrature harmonic current detection algorithm has been proposed in this paper , which is clear, fast and accurate in calculation comparing with other harmonic current detection method .The simulation and experiment results verify the method.Finally a novel solution of harmonics current for relay protection of micro -grid has been provided.