The Study On Integrating Substation Quasi Real Time Data Into PI System

In order to facilitate data-processing with computer, the first step in power system information integration is to convert substation operation parameters into digital signal, so kinds of intelligent electronic devices (IED) are introduced into the substation. Now these IED can provide various data for power system operation, and possess the ability to transmission their data to the remote control center. Howe ever, a large number of IED data can not be used efficiently, that is the so-called "Island of Information" problem. There are mainly two factors resulting in the information waste: the absence of database which can store all the substation data makes data-sharing difficult;on the other hand, the variety of protocols which IED conform to complex the data-acquisition system. The use of Plant Information (PI) system in Power system eliminates the first factor, that is, the PI system acts as a unified data integration platform holding all substation data. This paper is to bridging IED and the PI system. The seamless communication of power system is based on the IEC 61850 Standard in the future, so our substation data-acquisition system is designed to abide IEC 61850 and based on common information model (CIM). The whole system consists of several slave stations installed in substations and a master station located in control center. The slave station performs data-acquisition & model-translation function. The master station manages all slave stations and passes IED data into PI system. The substation data-acquisition system not only has traditional data acquisition and communication functions, but also satisfies data-integrity and real-time requirements in power system information integration.