基于改进差流差压法对变压器能效分析

Analysis of Transformer Energy Efficiency Based on Improved Differential Current and Differential Pressure Method

在变压器能效计量的差流差压法基础上提出改进方法,不要求电压、电流互感器变比与待测变压器相同,可根据变压器等级与测量仪器选择最适宜的高精度互感器。改进方法保留了差流差压法损耗测量较高精度的特性,同时可实现在线能效测量。随后利用改进方法进行试验,分别对单相试验变压器在工频下的损耗、效率及三相电力变压器在谐波作用下的能效进行分析,得出变压器能效随电压、负载、谐波含量和谐波次数变化的规律。

An improved method based on differential current and differential voltage method for energy efficiency measurement of transformer was proposed.The transformer ratio of voltage and current transformer was no longer required to be exactly the same as the transformer to be tested.The most suitable high-precision transformer can be selected according to transformer grade and measuring instrument.The improved method retained the characteristics of high accuracy of loss measurement and realized on-line energy efficiency measurement at the same time.Subsequently,the actual test analysis was carried out by using the improved method,and the loss and efficiency of single-phase test transformer under power frequency and energy efficiency of three-phase power transformer under harmonic were analyzed respectively.The variation rule of transformer energy efficiency with voltage,load,harmonic component and order of harmonics was obtained.