超低频波形信号源保护用电流互感器励磁特性试验方法

Study on the V-A Characteristic Test New Method of Protection Current Transformer Based on Super Low Frequency Arbitrary Waveform Signal Source

目前保护用电流互感器励磁特性试验的工频试验方法和低频正弦波试验方法都存在着一定不足之处,主要针对目前存在的问题,参考Lucas模型建立了一种超低频任意波形信号源对保护用电流互感器进行励磁特性试验的分析计算方法。该方法把电流互感器的励磁电流分离为涡流损耗电流和磁滞损耗电流两个部分,测量相关的诸如互感器铁心损耗、基本磁化曲线和极限磁滞回线等参数,充分考虑直流电阻上产生电压降的影响,通过计算得出工频下励磁特性数据。本文打破传统运用工频和低频正弦波进行励磁特性试验的约束,充分考虑电流互感器的铁心饱和、磁滞和直阻等因素影响,建立一种任意波形、超低频率信号励磁的模型和计算方法,并通过大量试验对比验证说明此方法是准确和可靠的。

Because of protection current transformer excitation characteristic based on power frequency test method and low frequency sine wave test methods having some shortcomings currently, the paper mainly aimed at the problem above, and established one method of analysis and calculation that the excitation characteristic test was carried out on the protective current transformer by using super low frequency arbitrary waveform signal source referring to the Lucas model. Through the excitation of the current transformer was divided into two parts of eddy loss current and hysteresis loss, and measured related parameters such as transformer core loss, basic magnetization curve and hysteresis loop, and fully considered the influence of the voltage drop on the DC resistance, the method obtained the V-A characteristic data of power frequency by calculating. Breaking the constraints of excitation characteristic test carried out by the traditional way of power frequency and low frequency sine wave, the paper considered the impact of CT core saturation, hysteresis and DC resistance and other factors, and established the model and a calculation method for arbitrary waveforms, super-low frequency signal excitation, and showed that the method verified by comparing a large number of tests was accurate and reliable.