并列运行高阻抗变压器间涌流相互作用及其对继电保护影响的认识和探讨

Discussion Study on the Theory of Interaction Between Inrush Current of High-impedance Transformers in Parallel Operation and Its Effect on Relay Protection

和应涌流是继电保护研究的热点课题之一,和应涌流容易对变压器的保护产生不利影响。本文以一起高阻抗空投变压器误动事故为背景,分析了并列运行变压器涌流间相互作用并探讨了高阻抗变压器励磁涌流衰减的特点。研究结果表明涌流间相互作用是导致过流保护误动的主要原因。然后针对本次误动原因探讨性的提出了设想措施。仿真实验验证了设想措施的可行性。

Sympathetic inrush is one of the most important topics for relay protectors, which has bad effects on transformer protection. The paper takes a high impedance transformer as an example to analyze the interaction between inrush currents in parallel operation transformers and analyzes the decay characteristic of excitation inrush current in high impedance transformer. The analysis result shows that the interaction between sympathetic inrush and excitation inrush current is the main reason for the mal-operation. In the end, countermeasures are put forward to avoid the mal-operation and simulations prove the countermeasures are reasonable.