The invention relates to a localized component protection system, comprising at least one protection sub-machine, wherein the protection sub-machine comprises an auxiliary control device and a protection control device; the auxiliary control device is provided with a time tick receiving port and a communication port; the auxiliary control device is connected with a first information collecting device and a second information collecting device; the protection control device is connected with a third information collecting device; the auxiliary control device is configured to receive and synchronize two pieces of data information of a protected device, to send the two pieces of synchronized data information to a substation SV network, and to start logic identification according to one pieceof the data information; and the protection control device is configured to receive one piece of data information of the protected device for protection of logic identification and start of logic identification, and to output a protection operation signal when the start of logic identification and the protection of logic identification are both performed. The localized component protection systemin the invention directly integrates the functional mode of a merging unit on the original relay protection device, and can still meet the requirement for high reliability of relay protection on the basis of integrating the function of the merging unit.