A power utility in-house automated disturbance recording system using protection IEDs, Modbus and python

The advancement in digital electronics and communication technology has enabled the integration of protection, metering, communication, control, digital fault recording in one intelligent electronic device (IED). A typical electrical grid has hundreds of these IEDs installed in substations for monitoring and protection purposes. When fault disturbances occur in the power system, these IEDs record analogue and digital signals and sequence of events critical for the operation of the grid. In view of the economic impact of electric grid disturbances, electric utilities worldwide implement automated disturbance recording and analysis systems (DRAS) which make use of dedicated disturbance recorders. For utilities managing large networks with thousands of IEDs and hundreds of substations, installing dedicated disturbance recorders to achieve the needed level of monitoring of the grid may not be economical. In this paper, a power distribution utility in-house automatic disturbance retrieval solution using legacy protection IEDs in a brownfield substation, Python scripting and Modbus is presented. The paper discusses a data warehouse architecture to guide the implementation of this system on an enterprise level.