基于电压、电流信息的变压器保护原理分析

分析研究了3种综合利用电压、电流信息的变压器保护原理,分别是磁通特性原理、等值方程原理和功率差动原理。磁通特性原理利用变压器铁心磁通变化规律来区别变压器运行状态,但是磁通难以直接测量且计算困难;等值方程原理根据利用正常运行绕组参数和电压、电流数据构建的方程是否成立来判别变压器运行状态,其关键问题是绕组参数的获取和门槛值的整定;功率差动原理基于能量守恒定律,较真实地反映出变压器工作在不同状态下的能量变化,但是在励磁涌流状态下需要延时1个周期来实现识别。利用动模实验数据验证了这3种原理的可行性,分析比较了其动作性能,指出算法实现中门槛值整定困难是制约其应用的主要问题,并给出了改进的方向。

Analysis of transformer protection principle based on voltage and current information

Three transformer protection principles synthetically using the information of voltage and currenare analyzed and studied.The magnetic flux characteristics principle applies the law of core magnetic fluxvariation to identify the transformer operating conditions,but it is difficult to directly measure and calculatethe magnetic flux.The equivalent equations principle identifies the transformer operating conditions accordingto the equations built with the winding parameters and the information of voltage and c...