Procjena pouzdanosti opreme tijekom životnog vijeka metodama vjerojatnosne analize sigurnosti

doctoral thesis

• Author: Ivan Vrbanić
• Mentor: Vladimir Mikuličić (mentor)
• Committee member: Danilo Feretić (član povjerenstva)
• Committee member: Vladimir Mikuličić (član povjerenstva)
• Committee member: Željko Bogdan (član povjerenstva)
• Committee member: Dubravko Pevec (član povjerenstva)
• Committee member: Nenad Debrecin (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Energy and Power Systems); Zagreb
• Defense date and country: 2004-12-22, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Electrical Engineering; Power Engineering
• Universal decimal classification (UDC): 620 - Materials testing. Power stations. Economics of energy ; 004 - Computer science and technology. Computing. Data processing

Abstract

Disertacija razmatra procjenu pouzdanosti opreme tijekom životnog vijeka utemeljenu na metodama vjerojatnosne analize sigurnosti. Koristi se vremenski ovisan model rastuće brzine kvara utemeljen na Weibullovoj raspodjeli. Učinak servisiranja opreme je uključen u model rastuće brzine kvara metodom srazmjernog smanjenja stupnja starosti, pomoću faktora poboljšanja. Ovaj model korišten je za vremenski ovisnu procjenu dvaju najvažnijih parametara opreme kod vjerojatnosne analize sigurnosti: brzinu kvara opreme u pogonu i neraspoloživost uslijed kvara opreme u stanju pripravnosti. Odgovarajući parametri modela procjenjuju se Bayesovom analizom. Za potrebe Bayesove analize, definirane su funkcije vjerodostojnosti za slučaj s opremom u pogonu, te za slučaj s opremom u stanju pripravnosti. Postupak procjene parametara i predviđanja vremenski ovisnih pokazatelja pouzdanosti demonstriran je, za oba razmatrana slučaja, na primjerima s pretpostavljenim pogonskim povijestima i strategijama održavanja opreme. Uključen je i primjer s uzastopnom provedbom Bayesove analize. Postupak procjene vremenski ovisnih parametara opreme primijenjen je na odabranu sigurnosnu opremu uključenu u model vjerojatnosne analize sigurnosti nuklearne elektrane. Uključeni su prikazi dobivenih rezultata s opažanjima i tumačenjima. Disertacija se završava zaključcima i preporukama za daljnja istraživanja.

Abstract (english)

Doctoral thesis deals with evaluation of life cycle equipment reliability based on methods of probabilistic safety assessment. Time-dependent model of increasing failure rate is used based on Weibull distribution. The effect of equipment overhauls is incorporated into the model of increasing failure rate by means of proportional age reduction method, with improvement factor. This model is used for time dependent assessment of the two most important parameters in probabilistic safety assessment: failure rate of equipment in operating state and unavailability of equipment due to failure in standby state. Appropriate parameters are estimated by Bayesian analysis. For the purpose of Bayesian analysis, likelihood functions were defined for the case of operating equipment, as well as equipment in standby state. The process of parameters' estimate and prediction of time dependent reliability indicators has been demonstrated, for both cases considered, on examples with assumed operational histories and maintenance strategies. Example with successive implementation of Bayesian analysis is also included. The process of time-dependent parameters' estimate has been applied to selected safety class equipment included in probabilistic safety analysis model of nuclear power plant. The results obtained are presented, together with observations and interpretations. Doctoral thesis ends with conclusions and recommendations for further research.

• Keywords: Vjerojatnosna analiza sigurnosti; procjena pouzdanosti tijekom; životnog vijeka; vremenski ovisna rastuća brzina kvara; rizik; oprema u stanju pogona; oprema u stanju pripravnosti; Bayesova analiza parametara pouzdanosti
• Keywords (english): Probabilistic safety analysis; life-cycle reliability evaluation; time-dependent increasing failure rate; risk; equipment in operating state; equipment in standby state; Bayesian analysis of reliability parameters
• Language: croatian
• URN:NBN: urn:nbn:hr:168:084745
• Study programme: Title: Doctoral study programme "Electrical Engineering and Computing"; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, po-dručje tehničkih znanosti (doktor/doktorica znanosti, po-dručje tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Repository: FER Repository
• Created on: 2019-06-26 07:42:06