Early Assessment And Prediction Of Workload For Main Control Room Operators At Nuclear Power Plants

Most of the current main control room operator workload assessment mainly takes place in the V&V phase of the Main Control Room(MCR)design of Nuclear Power Plants(NPPs),measured through simulation experiments,the measurement results can be used to improve the system design,and to some extent,can reflect the scientific nature of the main control room HMI design.However,this method has obvious shortcomings: assuming that the irrationalities of the design are found at the later stage of the main control room design of NPPs,improving the design problems at this time will cause the MCR design cycle to be prolonged and the design costs to increase,resulting in a great waste of time and resources.Therefore,the development of a scientific method to assess the workload of the Operator in the early stages of the MCR design of NPPs is of great significance to the efficiency and economy of the human-machine interaction design of the MCR of NPPs.This paper investigates the workload measurement methods in nuclear power and aerospace related industries at home and abroad to determine the VACP method based on the minimum task demand perspective,and improves this method for the task characteristics of the digital MCR of NPPs,and finally identifies a workload assessment and prediction method applicable to the early stages of NPPs design.The main research results include the following.1.Investigate,analyze,compare and demonstrate the Operator workload assessment methods in nuclear power,aerospace and other related fields at home and abroad to determine the Operator workload assessment method-VACP method based on the minimum task perspective.2.Improve the VACP method for the task characteristics of the MCR of digital NPPs,determine the VACP assessment scale based on the tasks of the digital MCR,and establish a Operator task execution model for the digital MCR with reference to the task flow of the digital MCR.3.Two types of classical scenarios in the early stages of NPPs were used to establish targeted assessment indicators to evaluate the workload levels in the corresponding scenarios,and secondly,a task-specific workload level indicator selection method was determined.1)Operator workload level assessment method without considering time pressure.In the context of very sufficient time under the normal operating conditions of NPPs,when the Operator performs the work of the Pressurized Water Reactor(PWR)NPP at full power under the loss of coolant accident,the Operator workload is evaluated under the loss of primary and auxiliary feed water during the handling of the accident.2)Operator workload level assessment method considering time pressure.Assessment of Operator workload levels under available time shortage in the event of an emergency condition.This study aims to accomplish the goal of Operator workload prediction for the MCR of NPPs by improving and establishing a dynamic VACP workload prediction method prior to the design phase of the plant.