Research On Control Method Of Integrated Small Reactor Power System

Integrated small reactors have high flexibility and safety,and will have a wide range of application prospects.At the same time,the proportion of nuclear power generation in the national power generation is increasing.When integrated small reactors(hereinafter referred to as integrated small reactors)participate in the power grid When generating electricity,it needs to participate in the frequency and peak regulation of the power grid.This requires the integrated small reactor to quickly track the load.It is necessary to study the integrated small reactor control strategy to meet the stable operation of the first loop and the second loop under variable load conditions.Therefore,this paper designs a control strategy to simultaneously control the steam pressure and superheat of the once-through steam generator to improve the overall control performance of the integrated small reactor.And on this basis,an integrated coordinated control scheme is designed.This paper first established an integrated small reactor thermal-hydraulic model,and carried out steady-state calculations to verify the rationality of the built model.On this basis,the integrated small reactor control strategy can be studied.Secondly,a control strategy to control the steam pressure and superheat of the once-through steam generator is designed,and the steam pressure and superheat PI controller and the fuzzy PI controller are designed at the same time,and the control performance of the traditional PI control method and the fuzzy PI control method are compared.The simulation results show that it is feasible to control the steam pressure and superheat at the same time,the steam pressure and superheat can be stabilized at the set value,and the fluctuation range of the steam superheat relative to the feedwater control steam pressure control system is small;the fuzzy PI control is relative to the PI control The adjustment time is significantly shortened.Finally,the coolant average temperature control system and the regulator pressure control system are designed.The PI control algorithm and the fuzzy control algorithm are applied to the regulator pressure control system,combined with the steam pressure and superheat control strategy of the once-through steam generator,to design Integrated small reactor PI coordinated control system and fuzzy PI coordinated control system.The simulation results show that the fuzzy PI coordinated control system has a shorter adjustment time than the PI coordinated control system,and the fluctuation range of steam superheat,stabilizer pressure and average coolant temperature is smaller,and the advanced coordinated control system has a smaller steam pressure overshoot during the load increase process.,The fluctuation range of steam pressure in the load reduction process has not improved significantly.In addition,there is a large margin for the core MDNBR,core temperature,and fuel cladding temperature during the load-lifting process.The control strategy of the once-through steam generator designed in this paper better meets the control performance requirements of the once-through steam generator,the superheat is stable at the set value,there is no big fluctuation,and the steam quality is improved.On the basis of the once-through steam generator control strategy,an integrated small reactor coordinated control system is designed,which can better study the overall control performance of the integrated small reactor,and the control effect of the integrated small reactor control system better meets the needs of the power grid.