关于主变保护空投动作的分析及应对措施

Analysis and Countermeasures of Protection Malfunction Caused by Main Transformer No-load Operation

主变压器在空投时由于励磁涌流的影响往往会造成保护的误动,为了避免此种情况的发生,有的保护装置采用了采样值差动原理来避免保护装置误动。通过对现场一起主变空投时保护装置的动作进行了分析,得出引起此次保护动作的原因,判断保护动作的正确性,从而针对问题提出了改进措施,希望能够对电网的安全稳定运行有所帮助。

No-load operating of the main transformer may cause protection malfunction due to the influence of excitation inrush current. In order to avoid the happening of this kind of situation, the sampling value differential protection principle is adopted to avoid protection malfunction. According to the analysis on a case of protection malfunction caused by no-loading operating, the causes were concluded and measures are put forward for improvement so as to ensure the safe and stable operation of power grid.