Cigré/Brasil
CE B5 – Proteção e Automação
Seminário Interno de Preparação para o
Colóquio de Madri 2007
Rio de Janeiro, outubro/07
Dados do Artigo
• Número 111
• Título
Verification of Utility Requirements on
Modern Numerical Busbar Protection by
Dynamic Simulation
• Autoria
Zoran Gajic, JP Wang, PW Gong, YS Xu,
ZX Zhou
• País
Sweden, China
Objetivo
• This paper presents a set of requirements posed on busbar
protection by Chinese transmission
• system operator. In order to approve a busbar differential
relay to be used in the Chinese transmission
• grid its performance must be verified by the national testing
institute. Test setup and actual test results
• for one particular implementation of a modern numerical
busbar protection are presented.
• Performance of the busbar protection relay is verified on an
analogue power system simulator for
• different operating conditions for the busbar protection
scheme such as external faults with and
• without CT saturation, internal faults, evolving faults, faults
during power swing, etc.
Destaques
•
The numerical busbar protection has been tested on an analogue power system simulator in
order to verify that it can handle both station configurations. Different operating conditions for
the busbar protections have been tested as listed below:
 Internal and external metallic faults (i.e. without fault resistance)
 Internal faults with fault resistance
 Evolving faults
 Circuit Breaker Failure
 Power swing and faults during power swing
 Internal and external faults during active load-transfer for double-bus single-breaker
station
 CT saturation for external faults
 Open CT secondary circuits
 Line and power transformer energization
 Internal and external faults during off-nominal power system frequency condition
 Special test for one-and-a-half breaker station (internal faults with out-feed currents)
 DC power switching (off/on) while relay is in service and busbar is loaded
 Faults during off-nominal frequency conditions
 Internal and external metallic faults (i.e. without fault resistance)
•
Altogether 1528 test cases on an analogue power system simulator were performed
Dúvidas
• Double-bus single –breaker station layout
• Four feeder bays and one bus-coupler
• One-and-a-half-breaker
• Two full diameters
Why these busbar configuration?
Are them pre defined by CEPRI?
Conclusões
• After all these tests, the protection relay was officially
approved by CEPRI to be used for busbar protection
applications in China for all voltage levels up to and
including 500kV
Respostas às questões do REP
•
Número da questão
•
•
Questão
5
What are the main conditions to select one of the two available types of busbar
protection arrangements? What are the operational experiences with one or
another arrangement? Is there any differences regarding engineering, installation,
testing, commissioning and operation of these two types of busbar protection
arrangements? How is the DC power supply arranged for these two solutions?
•
Resposta:
Basically the main condition to choose one of the available
arrangements (centralized or decentralized) is the cost of the cables to be installed
in the relay room. New stations have a better cost benefit using decentralized
busbar protection. Existing stations have a better cost benefit with centralized
type.
Respostas às questões do REP
•
Número da questão
•
•
Questão
11
What are the practical experiences from the factory acceptance testing
and commissioning of numerical busbar protections? Is it easier to
perform commissioning of (live) stations with numerical busbar
protections then stations with the busbar protection using conventional
technology?
•
Resposta:
Live stations commissioning are easily done with numerical
busbar protection, as we can isolated bays and test each one individually
without compromising energised bays while testing others.
Also image replica of disconnectors can be simulated making tests easier
•
Respostas às questões do REP
• Número da questão
• Questão
12
• How is the disconnector replica tested for numerical busbar
protection relays?
• Resposta: In cold commissioning they are tested checking
real conditions. On live station they can be tested by
simulation and checking the digital inputs status. This can
be helpful to test specific bays at a time
Respostas às questões do REP
•
Número da questão
•
•
Questão
13
What are the main utility considerations when deciding to perform
approval testing of a busbar protection? When such tests are considered
necessary? How is the issue of busbar protection relay software version
handled in such approvals?
•
Resposta:
Not always dynamic tests are used to approval busbar
protection. Most of times they are used when utility is using the busbar
protection for the first time and have no experience with it.
Software version are normally by specification granted to last version.
Manufacturer has to delivery last version up end of warranty
•