暂态保护用小功率电流变换器的研究

小功率电流变换器在电力系统二次侧对电流实现隔离和变换。随着电力系统的发展，愈来愈要求电流互感器能在暂态过渡过程中真实地传变暂态故障电流。基于等值电路，对小功率电流变换器的暂态特性的影响因素进行了深入分析。为了更真实地传变非周期分量电流，应在保证小功率电流变换器不发生饱和的前提下，尽量提高二次回路时间常数。对于体积受限的小功率电流变换器，通过推导二次回路时间常数关于铁芯边宽的变化关系，提出了一种暂态小功率电流变换器的定量设计和计算方法，得到了在不同二次线径下的最优设计方案。理论分析结果与样品的测试结果吻合，得到了实践验证。

Research on low power current transducer used for transient protection

Low power current transducer insulates and converts current on the secondary side of the power system. As the power system develops, the current transformer is required to accurately convert transient fault current during the transition period. Based on the equivalent circuit, the influence factor of transient characteristic of low power current transducer is discussed in depth. In order to reach a more realistic effect of aperiodic component transmission, the secondary circuit time constant should be improved as far as possible under the premise that the low power current transducer does not saturate. For low power current transducer with restricted volume, by deducing the relationship between secondary circuit time constant and core width, a quantitative design and calculation method of the low power current transducer is proposed, and then the optimal design schemes are obtained under different secondary wire diameter. The theoretical analysis coincides with the test results of the samples, and the theory is verified by practice.