基于云理论的居民负荷集体谐波概率分布

Collective Harmonic Distribution of Residential Loads Based on Cloud Theory

电力电子型居民负荷和新能源装置在配电网中应用越来越广泛,其产生的集体谐波非常可观,对电力系统的影响与危害已不可忽视。文中提出一种基于云理论的居民负荷集体谐波评估方法,介绍了云模型和云变换的基本理论,阐述了基于云理论的居民负荷集体谐波评估流程。通过实际案例证明,采用云变换方法可精确拟合谐波电流概率分布曲线,能较好地呈现居民负荷谐波电流幅值分布曲线的多峰性,其95%概率最大值估计精度显著优于正态分布法。研究结果对分析居民谐波来源、确定谐波治理措施和监管政策具有重要意义。

With the ever widening application of power electronic based residential loads and new energy devices in distribution systems,very considerable collective harmonics that have non-negligible impacts on the power systems have been generated.Therefore,a collective harmonic assessment method based on the cloud theory for residential loads is presented.The fundamental theory of the cloud model and cloud transform is introduced briefly firstly.And then the procedure of the collective harmonic assessment of residential loads is illustrated in details.The analysis results of practical cases prove that the cloud transform is capable of fitting the harmonic current distribution curves in high precision,and presenting the multi-modal characteristics of the distribution curves well.The 95% maximum probability calculated with the cloud transform is much more accurate than the normal distribution method does.The research results are meaningful to analyze the residential harmonic sources and determine the harmonic control and supervision measures.