A. Lisowiec 1, A. Nowakowski 1, Z. Kołodziejczyk 1, B. Miedziński 2 1 Centre For Tele-Information Systems and Hardware Applications, Tele and Radio Research

A. Lisowiec1, A. Nowakowski1, Z. Kołodziejczyk1, B. Miedziński2

1Centre For Tele-Information Systems and Hardware Applications, Tele and Radio Research Institute2Institute of Electric Power Engineering, Wrocław University of Technology

Autonomous Tele-Information Network for Power Systems

Switchgear Equipment e-Diagnostics

EUROPEAN UNIONEUROPEAN REGIONAL DEVELOPMENT FUND

Project Number:WND-POIG.01.03.01-14-141/08

The research work presented in this paper is part of a development project cofounded by European Union within the European Union Structural Funds, POIG (Operational Programme Innovative Economy), project

number: WND-POIG.01.03.01-14-141/08.

Reasons for developing a comprehensive Reasons for developing a comprehensive system for Circuit Breaker diagnosissystem for Circuit Breaker diagnosis

• Circuit breakers have to be reliable since Circuit breakers have to be reliable since the safety of power network operation the safety of power network operation depends directly on them,depends directly on them,

• Circuit breakers are the elements of Circuit breakers are the elements of power network that are more susceptible power network that are more susceptible to damage than other equipment,to damage than other equipment,

• Circuit breakers are expensive to replaceCircuit breakers are expensive to replace



Basic requirements on the diagnostic systemBasic requirements on the diagnostic system

• The diagnosis of the CB has to be done The diagnosis of the CB has to be done on-line basing on the signals available on-line basing on the signals available during normal operation,during normal operation,

• Data acquisition has to be carried out by Data acquisition has to be carried out by devices that can also perform other devices that can also perform other functionfunctionss like protection relay, like protection relay,

• The transmission of all data within the The transmission of all data within the system has to be carried out according to system has to be carried out according to IEC 61850 standard,IEC 61850 standard,

• The decision/diagnosis of the CB has to The decision/diagnosis of the CB has to be be carried out autonomously by the network carried out autonomously by the network without any interference from human without any interference from human operatoroperator



TCT/IP

SUBSTATION ETHERNET BUS

SUBSTATION 2

CB

CTD

CB

CTD

SUBSTATION N

SUBSTATION 1

CORPORATECONTROLCENTRE

CDB

REMOTEOPERATOR

TCT/IP

TCT/IP

TCT/IP

TCT/IP

System architectureSystem architecture



CONC

Control device, CTD, architechtureControl device, CTD, architechture

CB SIGNAL CONDITIONING

D/A

CONVERTERMICROPROCESOR

TRANSMISSION

CIRCUIT

PROTECTION FUNCTIONS

ETHERNET CONTROLLER

CONTROLLING DEVICE



Conventional method of CB monitoringConventional method of CB monitoring

Signals acquired from Circuit Breaker Signals acquired from Circuit Breaker can be grouped according to different can be grouped according to different

criteria:criteria:



1.1. analog signals,analog signals,2.2. digital signalsdigital signals

1.1. high speed signals,high speed signals,2.2. slowly varying signalsslowly varying signals

1.1. signals at high voltage,signals at high voltage,2.2. signals at low voltagesignals at low voltage

Main signals acquired from CBMain signals acquired from CB

• auxiliary contact signals:auxiliary contact signals:• truck position contacts,truck position contacts,• main spring tension state main spring tension state

contactcontact• sensor signals,sensor signals,

• eg. sulfur hexafluoride pressere eg. sulfur hexafluoride pressere sensor signal,sensor signal,

• vibration signals,vibration signals,• temperature measurement temperature measurement

sensors,sensors,• dc voltagesdc voltages



Main signals acquired from CBMain signals acquired from CB

• phase currents,phase currents,• currents and voltages of tripping currents and voltages of tripping

and closing coils,and closing coils,• movement monitoring sensors movement monitoring sensors

signals,signals,• acceleration sensors signals,acceleration sensors signals,• digital signals,digital signals,• open initiate,open initiate,• close initiate,close initiate,



Concentrator software architectureConcentrator software architecture

DIGITAL FILTERING MODULE

SIGNAL PARAMETRIZATION

MODULE

EXSPERT SYSTEM MODULE

ALARMS NOTIFICATION AND REPORT

GENERATION MODULE



Signal parametrization methodsSignal parametrization methods

• Digital filtering,Digital filtering,• ResamplingResampling in digital domain – for protection in digital domain – for protection

functions realization,functions realization,• Decimation – for recorder purposes,Decimation – for recorder purposes,• Spectrum analysis, FFT,Spectrum analysis, FFT,• Wavelet analysisWavelet analysis



Analysis of current and voltage signalsAnalysis of current and voltage signals

• Contacts bounce time,Contacts bounce time,• Contact opening time and its Contact opening time and its

dependence on load current,dependence on load current,• Contact closing time and its Contact closing time and its

dependence on load current,dependence on load current,• Simultaneity of contacts closing Simultaneity of contacts closing

in three phases and its in three phases and its dependence on load current,dependence on load current,



Analysis of current and voltage signals, Analysis of current and voltage signals, cnt.cnt.

• Contact closing time averaged Contact closing time averaged over last 10 operations,over last 10 operations,

• Contact closing time averaged Contact closing time averaged over last 10 operations,over last 10 operations,



Expert system operationExpert system operation

EVENT CLASSIFICATIONe.g. CB tripping;

Based on the event, appropriate set of rules customized for each CB operation is used

SIGNAL CHARACTERIZATION AND VERIFICATIONEach signal describing the event is analyzed based on the rules of the expert system knowledge base. The purpose of this is to verify that the values of extracted signal

features conform to the expected values within given tolerances

VERIFICATION OF CAUSE – EFFECT RELATIONSHIP AMONG SIGNALSthe relationships involving multiple parameters and possibly multiple signals are analyzed

to determine the causes of observed signal features



Expert system operation, cnt.Expert system operation, cnt.

CB OPERATION VERIFICATIONThe actual breaker operation is compared with the patterns stored in the rules of the expert system and the settings, each of them customized for particular type of circuit

breaker and operation and specified by user

ANALYSIS REPORT GENERATIONAt the end of the analysis, expert system creates the report in the form of a text file. The report clearly describes the operation and performances of the circuit breaker, as well as

maintenance and repair recommendations if problems are detected.



Operating coil current diagramOperating coil current diagram



New non invasive methods of Circuit New non invasive methods of Circuit Breaker monitoringBreaker monitoring

• Temperature distribution monitoringTemperature distribution monitoring

• Spectroscopic methodsSpectroscopic methods



Temperature distribution monitoringTemperature distribution monitoring

DETECTOR

FIBRE

CB



Temperature distribution monitoringTemperature distribution monitoring

Taking the temperature distribution within the contact body

Comparing the taken temperature distribution with the reference

temperature distribution



Temperature distribution within the Temperature distribution within the contact bodycontact body



Spectroscopic method setupSpectroscopic method setup

DETECTOR

CB

FIBRE



Spectroscopic methodsSpectroscopic methods

Special construction of the contact body

Knowledge of the characteristic spectral lines of the materials used for contact construction

Selective diode detectors



Special construction of the moving part of Special construction of the moving part of the contactthe contact

contact base

contact coating

soldered layer



Emission spectrum of contact compound made of MolybdenumEmission spectrum of contact compound made of Molybdenum



arc – arching discharge, glow – glowing discharge, dat – data from physico-chemical tables

Emission spectrum of contact compound made of TantalumEmission spectrum of contact compound made of Tantalum




Emission spectrum of contact compound made of NickelEmission spectrum of contact compound made of Nickel




ConclusionConclusion

The research work presented in this paper is part of a development project cofounded by European Union within the European Union Structural Funds, POIG (Operational Programme Innovative Economy), project number: WND-POIG.01.03.01-14-141/08.

• TheThe developeddeveloped network is a very comrehensive network is a very comrehensive system for CB testing and diagnosis on-line; it system for CB testing and diagnosis on-line; it employs traditional as well as new methods of CB employs traditional as well as new methods of CB monitoringmonitoring

• The cost to the final user has been minimalized The cost to the final user has been minimalized because of the integration of protective, control because of the integration of protective, control and monitoring function in one deviceand monitoring function in one device

• The system uses modern approach through the The system uses modern approach through the adoption of IEC 61850 standardadoption of IEC 61850 standard



Documents

A. Lisowiec 1, A. Nowakowski 1, Z. Kołodziejczyk 1, B. Miedziński 2 1 Centre For Tele-Information Systems and Hardware Applications, Tele and Radio Research