低压配电网三相不平衡度计算方法与应用

低压配电网三相不平衡已成为广泛关注的共性问题,分析、评估及治理工作均需要准确的算法来保证。为了了解不平衡度估算算法在三相不平衡系统计算中产生的误差,研究电流序分量相角的变化对三种电流不平衡度算法的影响,进而选择一种最有效的、误差最小的估算方法。文中首先介绍了标准中电压和电流不平衡度的几种算法,理论推导了不平衡电压的产生的原因,并给出了不平衡电流的几种计算方法。在此基础上,通过MATLAB仿真实验研究了影响三种电流不平衡度估算方法的因素,并提出了可行性建议。文章最后通过实测数据的分析,验证了以上结论。文中对四种电流不平衡度估算算法的研究,对工程实践有很大的指导意义,对三相不平衡系统的治理与补偿提供一定的借鉴。

Calculation Method and Application of Three Phase Unbalance in Low Voltage Distribution Network

The three phase unbalance of low voltage distribution network has become a common problem of widespread concern. Analysis, evaluation and management need accurate algorithms to ensure. In order to understand the error produced by unbalanced estimation algorithm in three-phase unbalanced system, the influence of phase angle variation of current sequence components on the algorithm of three kinds of current imbalance is studied, and then a most effective and least error estimation method is chosen. This paper first introduces several algorithms of voltage and current unbalance in standard, theoretically deduces the cause of unbalanced voltage, and gives several calculation methods of unbalanced current. On this basis, the factors that affect the estimation methods of three kinds of current imbalances are studied by MATLAB simulation experiments, and some feasible suggestions are put forward. In the end, the above conclusion is verified by the analysis of the measured data. In this paper, the research of four kinds of current imbalance estimation algorithm has great guiding significance for engineering practice, and it can provide some reference for the treatment and compensation of three-phase unbalanced system.