Electromagnetic ring network is the product of the transition stage of power grid development. There are some stability problems such as transient stability and thermal stability after some electromagnetic ring network faults in China southern power grid，which make the operation of the main grid difficult control. In extreme cases，the operation risk is extremely high. In this paper，the typical electromagnetic ring network with problems of CSG is studied. According to the analysis of security and stability，the relevant operation of the electromagnetic ring network is formulated. The principle and operation requirements of the electromagnetic ring network are put forward，which can provide the reference for electromagnetic ring network operation.