计及角度不对称的配电网负荷不对称线损分析

针对当前研究配电网三相负荷不对称对线损的影响仅仅局限于三相大小不对称的情况,提出计及角度不对称的配电网三相不对称对线损有影响。通过分析三相不平衡线路的线损,用全电流经坐标变换的方法研究了计及角度不对称时的三相不平衡对线损的影响,推导出了线损增加率与相不平衡度的关系公式,并给出了配网中常见几种负荷不对称时的线损分析结果。通过对现场实测数据进行算例分析,结果表明考虑角度不对称时的线损增加率更接近于真实值,对准确地计算配电网中的线损更有指导意义。

Line Loss Analysis of Three-phase Unbalanced Circuit with Angle Asymmetry

At present,the studies of line loss affected by the three-phase do not consider angle asymmetry.So,theoretical line losses are different from statistical line losses.The condition that circuit loss is affected by the three-phase unbalanced circuit with angle asymmetry is studied in the method of full current transformed after the coordinates.Then the relational formula of line-loss increment rate and unbalanced degrees of phases is deduced.What is more,the exceptional cases of line-loss increment rate which is caused by the three-phase load unbalanced distribution is offered.The numerical result with a test indicates that when the angle asymmetry is considered,it approaches the realistic value nearer and is a better method to accurately compute the rate of circuit loss in power distribution systems.