The invention relates to an intelligent comparison-based online operation and maintenance method and a system for the secondary equipment of an intelligent substation, and provides the high-level application of a soft pressing plate in an intelligent substation. The application comprises the standardization design of the soft pressing plate and the intelligent alarm for the feeding and withdrawingabnormity of the soft pressing plate. Based on the realization of the above functions, the operation and maintenance complexity and the operation and maintenance uncertainty of the intelligent substation can be reduced. Meanwhile, the sequential control operation of a protection device is conducted, so that the one-click type sequential control of feeding and withdrawing protection and security measure isolation is realized. The feeding and withdrawing step of the protection device is immobilized, so that the risk of misoperation in the security measure process is effectively reduced. According to the above technical scheme of the invention, the pilot operation can be carried out in a certain 220 kV intelligent substation, and the running condition is good. Meanwhile, the intelligent level of the substation is improved to a great extent. The configuration of an interval intelligent device during the long-term expansion process is fully considered, and the concept of a replacement device is proposed. The power failure time in the long-term reconstruction and extension process is shortened. Moreover, the modeling is carried out based on the IEC61850 standard, and a theoretical foundation is laid for later strategy implementation.