配电变压器行波传变特性研究

提出利用配电变压器传变行波信号,解决配电线路行波故障测距中线路末端信号不易获取的问题,并对变压器的行波传变特性进行了研究。简要分析了故障行波信号的基本特征,确定了测距所用行波信号的特征频段,给出了行波有效传变对测量互感器的要求。建立了配电变压器行波传变特性分析的集中参数等值电路,并以实际的变压器参数为例对其行波传变特性进行了研究。分析结果表明,对于暂态行波信号,配电变压器具有较快的上升时间和较高的截止频率,能够有效传变行波波头信号,满足行波故障测距要求。现场试验结果证明了文中方法的可行性和有效性。

Study On Travelling Waves Transform Characteristic of Distribution Transformers

A new method using distribution transformer to catch travelling waves is proposed to solve the problem of catching travelling wave signals difficulty in feeders' terminal.Travelling waves transform Characteristic of transformers is studied.The paper briefly analyses basic characters of travelling waves generated by fault and confirms its selected frequency band.Then the demands to measurement transformers are presented when using which to catch travelling waves.Transformer equivalent circuit of analyzing travelling waves transform characteristic is built,meanwhile,the characteristic is computed and analyzed using the parameters of practical transformers.The results show that,for transient travelling waves signals,distribution transformers have much shorter risetime and higher cut-off frequency,so they can transform travelling waves surge effectively and meet the needs of fault location based on travelling waves.Experimental test verify the feasibility and correctness of the proposed method.