Analysis and techniques of data compression in smart grids in the context of IEC 61850 communication protocol

Abstract

A smart grid is characterized by a two-way communication between the generation and the loads in addition to the distributed energy resources, which dictated the integration of smart monitoring devices to achieve full observability of the network. In smart grid operation, the monitoring and the measuring devices such as smart meters, phasor measurement units (PMUs) and the intelligent electronic devices (IEDs) typically record the data and share the information across each level of the grid. In distribution substations, the data and hence the information is then further transferred throughout the supervisory control and data acquisition (SCADA) and the data control center using the communication protocols. As a result, a large amount of data is transferred among different monitoring devices, data control centers, and SCADA within the smart grid, which calls for new requirements for the communication channels and the storage capacities. Data compression is considered promising techniques to reduce the burden on the communication channels as well as the storage in particular during the smart grid operation. This thesis focuses on studying the data compression techniques when applied to power system disturbances in the context of the IEC 61850 communication protocol, which is extensively used in smart distribution substation automation. A proposed approach for data compression is introduced in this work and it is based on a combined wavelet-surrogate binary regression tree and a hybrid thresholding method. The proposed approach for data compression is tested experimentally in real-time in the context of IEC 61850 communication protocol and the performance is compared to the existing approaches for data compression. The results have shown that the implementation of the proposed data compression approach may lead to significant reduction in the number and sizes of the Generic Object-Oriented Substation Event (GOOSE) messages, which are exchanged between the IEDS and the SCADA within the smart distribution substation automation in smart grids.