电压法测变压器套管CT变比

Measurement of ratio at a bushing-type CT

阐述了电流互感器变比试验的必要性和特点,在简述了电流法、短路法测变压器套管CT变比试验的原理、特点以及主要缺点之后,提出了采用电压法不拆变压器套管CT测变压器套管CT变比试验的方法,分析了电压法测变压器套管CT变比试验的原理,试验时可能引起误差的主要因素。试验中采取的抗干扰措施,并在试验中采用伏安特性试验仪在套管CT二次侧加交流电压,测量一次侧电压和二次侧电压的方法,同时完成套管CT变比试验、伏安特性试验。

This paper states the necessity and the characteristics of the current transformer ratio test ,reviews two normal methods of the CT ratio test in brief, i.e. short-circuit method and ctLrrent method. It brings forward new method of the CT ratio test by measuring voltage in primary side and secondary side of the CT without disassembling it, and analyzes the theory and the main factors causing errors of the new method. In the test, it adopts anti-interference method and applies AC voltage on secondary side of CT with I/V characteristic instrument to measure voltage of primary side and secondary side. The CT ratio test and IN characteristic test are carried out as well.