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IEC 61850-9-2 based sampled values and IEC 61850-8-1 Goose messages mapping on an FPGA platformNcube, Alexander Mandlenkosi January 2016 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016. / Electricity substation monitoring and control systems have evolved over the years from simple systems capable of achieving minimalistic functions to autonomous, self-healing smart grid schemes (Farhangi, 2010). The migration of technology to networked smart grid systems was driven by the need for standardisation of communication networks, system configuration and also the reduction of system implementation costs and engineering time.
Before the introduction of a uniform communication standard, legacy (non-standardised) communication protocols, for example, the Distributed Network Protocol (DNP3) were used by Remote Terminal Units (RTUs) for information exchange (Luwaca, 2014). These communication protocols could not provide a standard naming convention or data semantics since the data/information was accessed using an address-based system. The implementation of automation systems based on legacy protocols and RTUs was expensive because of parallel copper wiring required to connect instrument transformers and circuit breakers to multiple RTUs for protection and monitoring functions (Iloh et al., 2014). Legacy systems refer to Supervisory Control and Data Acquisition (SCADA) systems implemented using RTUs and legacy communication protocols. Legacy systems tended to be vendor specific because devices from different vendors did not support the same communication protocol. These issues led to the introduction of the IEC 61850 standard. The IEC 61850 standard for “communication networks and systems in a substation” provides standardised naming convention, data semantics, standardised device configuration and also device interoperability and interchangeability in some instances. The IEC 61850 standard provides a solution to expensive parallel copper wiring and standardisation issues experienced with legacy protocols. In as much as the introduction of the IEC 61850 standard addresses problems experienced with legacy system there is still a need to provide inexpensive access to IEC 61850-compliant devices and effective knowledge transfer to facilitate implementation of automation systems based on this standard. The development of an IEC 61850-compliant device requires a specialised skillset and financial investment for research and industrialisation therefore only a few vendors manufacture these devices resulting in an increase in production and manufacturing costs. For this reason this research project develops VHDL modules for mapping IEC 61850-9-2 Sampled Value (SV) messages and IEC 61850-8-1 Generic Object Oriented Substation Event (GOOSE) messages on a Field Programmable Gate Array (FPGA) platform. Sampled values are used for transmitting current and voltage transformer (CT and VT) measurements to protection devices while GOOSE messages exchange information/commands between primary equipment (CT, VT and circuit breaker) and protection devices over an Ethernet network known as the process bus.
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Virtualization of a sensor node to enable the simulation of IEC 61850-based sampled value messagesLuwaca, Emmanuel January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Electrical Engineering
in the Faculty of Engineering
at the Cape Peninsula University of Technology
2014 / The IEC 61850 standard, “Communication networks and systems in substations” was
promulgated to accommodate the need for a common communication platform within
substations for devices from different vendors. The IEC 61850 standard proposes a
substation automation architecture that is Ethernet-based, with a “station-bus” for
protection devices within the substation and a “process bus” where raw data from the
voltage and current transformers are published onto the data network using a device
known as a Merging Unit.
To date, most of the standardization efforts were focused at the station bus level
where event-triggered messages are exchanged between the substation automation
devices, commonly referred to as Intelligent Electronic Devices (IEDs). These
messages are known as Generic Object Oriented Substation Event messages.
Equipment from vendors to accommodate the “process bus” paradigm, however is
still limited at present.
The Centre for Substation Automation and Energy Management Systems was
established within the Electrical Engineering Department at the Cape Peninsula
University of Technology with one of its objectives being the development of
equipment either for simulation or real-time purposes in compliance with the IEC
61850 standard. In order to fulfil this long-term objective of the Centre, an in-depth
understanding of the IEC 61850 standard is required.
This document details the efforts at acquiring the requisite knowledge base in support
of the educational objectives of the Centre and the research project implements a
simulation of a merging unit which is compliant with the functional behavior as
stipulated by the standard. This limited functional implementation (i.e. non-real-time)
of the merging unit, is achieved through the development of a virtualized data
acquisition node capable of synthetic generation of waveforms, encoding of the data
and publishing the data in a format compliant with the IEC 61850-9-2 sampled value
message structure.
This functional behavior of the virtual sensor node which was implemented has been
validated against the behavior of a commercial device and the sampled value
message structure is validated against the standard. The temporal behavior of the
proposed device is commented upon. This research project forms the basis for future
real-time implementation of a merging unit.
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Investigation of the application of IEC61850 standard in distribution busbar protection schemesMnguni, Mkhululi Elvis Siyanda January 2013 (has links)
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Electrical Engineering
in the Faculty of Engineering
at the Cape Peninsula University of Technology
Supervisor: Prof. R. Tzoneva
Co-supervisor: Prof. P. Petev
2013 / Busbars are the most important components in the distribution networks. Faults on the busbar are uncommon, however an occurrence of a busbar fault can lead to a major loss of power. Busbars are the areas in a substation where the levels of current are high and therefore the protective relay application is very critical. In order for the protection scheme to be successful it is important to carry out the following specifications: Selectivity, Stability, Sensitivity, and Speed. To meet all of the above requirements protection must be reliable, meaning that the protection scheme must trip when called up to do so (dependability) and it must not trip when it’s not supposed to (security).
The thesis focuses on the reverse blocking busbar protection scheme with aim to improve the speed of its operation and at the same time to increase operational reliability, flexibility and stability of the protection during external and internal faults by implementation of the extended functionality provided by the IEC61850 standard-based protective IEDs. The practical implementation of the scheme by the use of IEC 61850 standard communication protocol is investigated. The research analyzes in detail the reverse blocking busbar protection scheme that is used at the moment in the power systems and it develops an improved IEC 61850 based reverse blocking busbar protection scheme for a distribution network. The proposed scheme is designed for a radial type of a distribution network and is modeled and simulated in the DigSILENT software environment for various faults on the busbar and its outgoing feeders. The results from the simulations are used further for implementation of the designed protection scheme.
A laboratory test bench is build using three compliant with the IEC 61850 standard ABB IEDs 670 series, CMC 356 Omicron test injection device, PC, MOXA switch, and a DC power supplier. Two ways of the reverse blocking signals between the IEDs implementation are considered: hard wired and Ethernet communication by using IEC 61850 standard GOOSE messages.
Comparative experimental study of the operational trip response speed of the two implementation shows that the performance of the protection scheme for the case of Ethernet communication is better
The thesis findings and deliverables will be used for postgraduate studies of other students, research, short courses, and solution of industrial problems.
Keywords: Busbar, Power system, reverse busbar blocking scheme; IEC61850; Distribution, Protection relays, IEDs, GOOSE message, laboratory test bench
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Development of an embedded system actuator node for intergration into an IEC 61850 based substation automation applicationRetonda-Modiya, John-Charly January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Electrical Engineering
in the Faculty of Engineering
at the Cape Peninsula University of Technology, 2012 / The introduction of the IEC 61850 standard in substations for communication networks and
systems by the International Electrotechnical Commission (IEC) in 2003 provided the
possibility for communication between devices of different manufacturers. However, the
advent of this standard also brought about many challenges associated with it.
The challenges introduced by this fairly recent standard of communications in Substation
Automation Systems (SAS), and the need for the development of cost effective IEC 61850-
compliant devices, motivated the decision of the Centre for Substation and Energy
Management Systems within the Electrical Engineering Department of the Cape Peninsula
University of Technology to focus on the implementation of the IEC 61850 standard using an
embedded hardware platform.
The development of an IEC 61850 embedded application requires substantial knowledge in
multiple domains such as data networking, software modelling and development of Intelligent
Electronic Devices (IEDs), protection of the electrical system, system simulation and testing
methods, etc. Currently knowledge about the implementation of the IEC 61850 standard
usually resides with vendors and is not in the public domain.
The IEC 61850 standard allows for two groups of communication services between entities
within the substation automation system. One group utilizes a client-server model
accommodating services such as Reporting and Remote Switching. The second group
utilizes a peer-to-peer model for Generic Substation Event (GSE) services associated with
time-critical activities such as fast and reliable communication between Intelligent Electronic
Devices (IEDs) used for protection of the power network.
The messages associated with the GSE services are the Generic Object Oriented Substation
Event (GOOSE) messages. The use of GOOSE messages for protection of the electrical
system is very important in modern substations. Detailed knowledge of the structure of these
messages is important in instances requiring fault diagnosis to determine the cause of mal–
operation or to address interoperability concerns or when developing custom IEC 61850-
compliant devices with limited functionality.
A practical protection application (overcurrent) case study is presented where GOOSE
messages are exchanged between a commercial IED and an IEC 61850-compliant controller
based on an embedded platform. The basic data model and software development of an
actuator node for a circuit breaker is proposed using an IEC 61850 communication stack on
an embedded platform. The performance of the GOOSE messages is confirmed to be as per
the functional behaviour specified, and per the IEC 68150 standard in terms of the temporal
behaviour required.
This thesis document tables the methods, software programs, hardware interfacing and
system integration techniques that allow for the development and implementation of a low
cost IEC 61850-compliant controller unit on an embedded systems platform for the
substation automation system.
The overcurrent case study distributed between a commercial IED (SIEMENS Siprotec
device) and the actuator application developed on an embedded platform for this project
(DK60 board) is in compliance with the IEC 61850 standard and utilizing GOOSE messaging
is successfully completed both in terms of functional and temporal behaviour.
This novel research work contributes not only to the academic community, but to the
international Power Systems community as a whole.
Keywords: IEC 61850 standard, IEDs, GOOSE message, software modelling, software
development, substation automation systems, communication stack, embedded systems,
actuator.
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