Design And Development Of Digital Rod Control System And Rod Position Indication System In Third Generation Pressurized Water Reactor

Digital rod control system(DRCS)and rod position indication system(DRPI)are very critical systems in nuclear power plant.Both of the systems determine whether the plant could operate functionally.Global and domestic research show that digitalization has become a big trend for DRCS and DRPI.Currently,most of the DRCS and DPRI systems in China nuclear power plant are imported.Therefore,development of our own DRCS and DRPI system has strategic and economic significance.This article taking AP1000 nuclear power plant as study object,analyzes the functional requirement of the DRCS system and DRPI system,designs the control rod movement mode according to the distribution pattern of the control rod bundle,and puts forward the design object of DRCS system and DRPI system.Based on these fundamentals,digitalized DRCS and DRPI systems are designed here.In this article,we design the DRCS system starting from the control rod driving mechanism and control principle,use the three phase half-wave controlled rectifying circuit to establish the single control rod driving system,create mathematical model for this driving system using Simulink,and leverage fuzzy PID algorithm to optimize the control system to solve the influence from working temperature affecting the control performance found out by simulation.For the 69 control rods in the DRCS system,we will take one-control-four technology,use double side cabinets,LC control loop reuse technology and single rod control plan to realize the DRCS multiple rod control.In the design of the DRPI system,this article suggests to use the new inductive rod position indicator and data cabinet structure inside the containment,use address polling method to receive the rod position information interactively.The design of the DRPI system can lower the cost and enhance the system reliability by quick monitoring the Rod position and reducing the number of penetration assemblies.Furthermore,the reliability of DRCS and DRPI are also analyzed in this article as well as focusing on building the reliability architecture model of the logic cabinets,and coming to the conclusion of reliability index of the reliability and failure rate.At the same time,this article also establishes the logic cabinet's reliability block diagram,and provides the predication and evaluation of DRCS system and DRPI system.