For Functional Safety Assessment Of The Elevator Brake System Evaluation

Elevator safety problem has become a hot topic of current society.Elevator brakingsystem is the core components of the guarantee of elevator safety operation,whether it canwork reliably is particularly important.Recently there are many trapped people even personnelcasualty accidents because of the elevator braking system fault,bringing a great threat to thesafety of people’s life and property, also causing the bad social effect.Therefore, it has veryimportant engineering value and social significance to carry out the functional safetyevaluation of elevator braking system.The major work of present paper are as follows:(1)Based on method of functional safety evaluation, functional safety integrity level ofelevator braking system was distribute through the risk graph method, and established therequired safety standard and safety integrity specification.(2)Functional safety evaluation system of elevator braking system was established basedon FMEDA. By using the evaluation method of FMEDA,the elevator braking system wasdecomposed into sensor sub module, the logic control module and the final component submodule,and then the assess functional safety of modules respectively.(3)Random hardware failure evaluation parameter correction model of elevator brakingsystem was established. Correction value of the sensor module was determined according tothe elevator fault statistic by age; the value of logic control module was determined accordingto the failure probability calculation formula of sub components provided by GJB/Z299C-2006 and was modified according to the field measurement data; the value of the finalcomponent sub module is modified based on the elevator stop parameter and evaluation ofbrake structure.(4)The software of functional safety assessment system of elevator brake system wasprogrammed. The software was running on Android platform,which could get the elevatorbraking system functional safety integrity level quickly and accurately.The main features areas follows: safety assessment model parameters input, call and modification, safety evaluationinformation input,safety evaluation calculation, evaluation results show etc.. The program issimple, suitable for application of site evaluation.(5)Application of the results of study on the brake system for elevator safetyevaluation.The result of research on this topic has carried out the evaluation of severalelevator braking system functional safety in the city of Guangzhou,and achieved good results.