Modification of in-service substation based on IEC 61850

The standard IEC 61850 contributes the manufacturers and the end users. But it also makes many obstacles to the modification of the conventional substation. This paper presents a scheme which modifies an in-service conventional substation gradually to a modern substation which conforms to IEC 61850 standards. The procedure of the modification is divided into three stages. During the first stage, all the preparations have been finished. All the configurations and joint tests have been done before shipment. The secondary stage is to construct the substation network. New Human Machine Interface (HMI) and communication gateway will replace the old ones. They simultaneously support protocol of the existing system and IEC 61850 standards. The third stage is the modification of the bay level devices. The old cabinets and the cables out of the cabinets are kept. The inner IEDs are replaced. The connections between the IEDs and the cabinets also need to be re-arranged. The modification of bay can be done one by one according to the overhaul plan. The process is stable and secure, and it won´t affect the normal operation of the substation.