Simulacije povezane z regulacijo moči tlačnovodne jedrske elektrarne

GORIŠEK, ROMAN (author), Čepin, Marko (mentor)

Jedrske elektrarne so objekti, v katerih vzdržujemo jedrsko verižno reakcijo, pri čemer nastaja toplota, ki jo preko hladila in uparjalnikov vodimo v turbino, ki vrti generator, kjer poteka pretvorba v električno energijo. Magistrsko delo predstavlja modeliranje reaktorja v tlačnovodni jedrski elektrarni, ki vpliva na moč jedrske elektrarne in na količino električne energije pridobljene v jedrski elektrarni. Obravnava vpliv prehodnih pojavov na regulacijo moči in posledično na reaktivnost v jedrskem reaktorju. V ta namen smo s pomočjo programskega paketa Matlab napisali lasten računalniški model. Slednji nam analizira poljubne parametre, ki vplivajo na moč in reaktivnost reaktorja. V teoretičnem delu smo v začetnih poglavjih opisali regulacijo tlačnovodne jedrske elektrarne. Nato smo prikazali življenjski cikel nevtrona in faktorje, ki vplivajo na spremembo reaktivnosti v sredici tlačnovodnega jedrskega reaktorja. Slednja je merilo relativnega odmika od kritičnosti reaktorja oziroma eden glavnih parametrov delovanja. V nadaljevanju smo opisali, kako vplivamo oziroma kompenziramo reaktivnost. Temu sledi opis parametra rezerva zaustavitve, ki je pomemben za varno delovanje jedrske elektrarne. Glavni del naloge predstavlja računalniški model, napisan v programskem jeziku Matlab. S pridobljenimi podatki za 29. gorivni ciklus Nuklearne elektrarne Krško smo preučili posamezne vplive na reaktivnost in posledično na moč jedrske elektrarne. Z vnosom vhodnih podatkov model izračuna oziroma prikaže, kakšen vpliv imajo regulacijske palice, koncentracija ksenona in samarija na spremembo moči in posledično na reaktivnost sredice tlačnovodnega reaktorja. Sledi model za izračun rezerve zaustavitve. Rezultati kažejo vpliv regulacijskih palic in časovne poteke koncentracij ksenona in samarija, izražene v enoti za reaktivnost pri različnih spremembah moči reaktorja.

• Language: Slovenian
• Keywords: regulacija, reaktivnost, jedrska elektrarna, reaktor, nevtron
• Work type: Master's thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2018
• PID: 20.500.12556/RUL-103184
• Publication date in RUL: 14.09.2018

Secondary language

• Language: English
• Title: Simulations related to the power control in a nuclear power plant with pressurized water reactor

Abstract

Nuclear power plant is a facility where the process of nuclear chain reaction is maintained in a reactor and with it the heat produced. That heat is than passed through coolant and steam generators. This causes water to evaporate and propel the turbine which drives the generator where the transformation of mechanical energy to electrical energy takes place. This master thesis presents a model of pressurized water reactor (PWR) in nuclear power plant which has an effect on the output power of nuclear power plant and the amount of electrical energy it produces. In thesis we explored impact of transient phenomena on power control and consequently on reactivity in nuclear reactor. The model was made in Matlab and it enables us to analyse how different parameters impact output power and reactivity. In theoretical part we first described control of nuclear power plant with PWR. Than we presented the life cycle of a neutron and factors which have an effect on reactivity in the core of PWR. Reactivity is an important parameter since it is a measure of relative deviation from reactor’s critical point. Furthermore we have described how to impact and compensate reactivity. Lastly shutdown margin parameters, which are vital for safe operation of nuclear power plant, are described. Main part of the thesis represents a model made in Matlab. With the data obtained for 29th fuel cycle of nuclear power plant Krško we studied how different parameters affect reactivity and output power of nuclear power plant. With the insertion of input parameters created model gives us insight into how control rods, concentration of xenon and concentration of samarium impact the output power and reactivity in the core of PWR. After that a model for shutdown margin was established. Final results show the impact control rods and also how concentration of xenon and samarium changes in time. Concentrations are expressed in units for reactivity for different power changes of reactors.

• Keywords: control, reactivity, nuclear power plant, reactor, neutron