Data flow control and performance evaluation of IEC 61850 substation automation system

• Main Author: Dong, Fangfang
• Format: Dissertation
• Language: English
• Published: University of Manchester 2019
• Subjects: Data flow control; FIFO WFQ PQ; IEC61850; OPNET modeling

The Power substation primary plant has an average lifetime of around 40 to 50 years, which renewed only when they are physically or mechanically life-expired. Secondary equipment that has integrated the information & communication technology (ICT) has typically an average lifespan of approximately 10 to 15 years. This requires at least once or twice replacement and maintenance for the secondary equipment. Since the technological obsolescence has become a significant concern, due to the speed of the new evolutions for ICT products, the continuous upgrading of the software or firmware for the Intelligent Electronic Devices (IEDs) will increase the maintenance frequency. The maintenance and commissioning are usually having long outage time, which considered high risk and high cost. Hence, this requires a solution for the above issues. To solve the above issue and to provide the interoperability for multi-vendor IED, the International Electrotechnical Commission (IEC) 61850 standard has defined as the unique communication protocol for substation automation before the IEC 61850-based digital substation can be full implement, some crucial tasks required to investigate, such as data flow control and performance evaluation. This thesis presents a data flow control method for the IEC 61850-based substation automation system (SAS). It proposes the priority queueing method and applies it to the AS3 architecture to improve the dynamic performance of the system. The performance of the SAS has been evaluated using the event-based simulation tool, OPNET. Two alternative queueing methods have considered comparing the performance. It simulation results show that the priority queueing method has better performance than the WFQ and FIFO in series conditions. The thesis has presented the modelling of the IEC 61850-based network component and message traffic in detail. The performance of the process bus and station bus have been evaluated, and the capability of each network has been analysed based on the IEC 61850 performance requirements. This thesis has also considered the probability study using mathematical models to evaluate the AS3 architecture. It classified all the messages that contain in the IEC 61820-based SAS into three types, i.e. cyclic data, stochastic data and burst data. The mathematical model has been used to evaluate the performance of the station bus under different MMS updated rate. Moreover, the thesis has investigated the IEC 61850 traffic behaviour based on the laboratory setup. The characteristic of the MMS, GOOSE and SV traffic have been examined in real-world conditions.