计量用电流互感器在3种铁心条件下传变特性的试验与分析

Measurement and Analysis of Transfer Characteristics of Metering CT with Three Different Core Materials

计量用电流互感器(TA)作为最前端信号源器件,其性能直接影响电力仪器仪表的测量精度。文中通过试验与分析3种常用铁心TA的传变特性得出:TA的传变特性与铁心材料有关,具有非线性特性;超微晶铁心、坡莫合金铁心的TA传变特性明显优于硅钢片铁心的TA;用坡莫合金铁心和超微晶铁心的TA准确度可以达到0.1级;用硅钢片铁心TA准确度可以达到1级。选择性能优良的铁心材料,优化结构,是提高TA传变特性行之有效的方法。

As the forefront signal source, the properties of current transformer （CT） for metering directly affect the precision of electric instrument. Through the experiment and analysis of transfer characteristic with three kinds of core materials, the results show that the CT＇ s transfer characteristics have nonlinear characteristics associated with the core material. The transfer characteris- tics of CT with super microcrystalline core and permalloy core are obviously better than that of silicon steel sheet core. The preci- sion of CT with permalloy core and super mierocrystalline core is up to 0.1%. The precision of CT with silicon steel sheet core is up to 1%. Making a good choice of core material and optimizing structure are the effective ways to improve the CT＇s transfer character- istics.