The mal-operation of non-electricity protection for the transformers is the problem that people pay close attention to very much.
变压器非电量保护的误动问题，一直是人们非常关注的问题。
2
It USES the positive impedance in static stability and low-voltage impedance which can effectively prevent the mal-operation in external faults.
静稳阻抗和低电势阻抗采用正序阻抗，能有效地防止外部短路造成的误动作。
3
The saturation of magnetic current transformers, occurred during a fault on the power system, will lead to mal-operation or refused operation of protection relay.