Study On The Monitoring And Evaluate Method Of Elevator Braking Performance

As a vertical transport tool,with the rapid increase of the quantity of the elevator,the accidents caused by the elevator failure and the wounded are becoming more and more frequent,which seriously endangers the social security.As one of the core safety components of the elevator,the performance of the braking system directly affects the safety of the elevator operation.In this paper,the monitoring and analysis methods of vertical traction elevator's braking performance are studied.The main contents are as follows:The braking force,the acceleration of braking,the change of brake inner energy and the change of the temperature field of the brake are carried out in the process of elevator braking,Matlab and ANSYS are used to model and simulate the change of the brake shoe temperature field in the braking process under different operating conditions of the elevator,the normal elevator and the brake performance failure elevator's brake shoe temperature field change are obtained.In view of the lack of quantitative evaluation of elevator braking performance,a quantitative evaluation method of elevator braking performance based on a Bagging-RNN model is proposed.The infrared thermal image of the brake shoe during the elevator braking process is obtained,the brake shoe's temperature data are gotten after processing the image,the brake shoe's temperature data are trained and the Bagging-RNN model is gotten with good generalization performance,which is the model of quantitative evaluation of the elevator braking performance,the effectiveness of the performance evaluation method is verified by the simulation data.In order to solve the problem of uneven wear detection of brake shoe,a method based on thermal image analysis and discrete frechet distance is constructed.The infrared thermal image of the brake shoe during the elevator braking process is obtained,and the salt and pepper noise and gauss noise in the thermal image are filtered by median filter and mean filter method,and the edge vector of the infrared thermal image is obtained by the Canny edge detection algorithm,a method based on threshold discrimination is proposed to extract the vector of the brake shoe's isotherm,and the similarity degree of the edge vector and the isotherm vector is calculated by the discrete frechet distance,and the uneven wear of the brake shoe is detected according to the correlation of the similarity between the two vectors and the uneven wear of the brake shoe,the uneven wear detection method is verified by the analysis results of simulation data.The braking performance monitoring system of elevator is developed.SQL Server software is used to establish the database server of the monitoring system.The software of the elevator braking performance monitoring system is developed using C# language.The software of the elevator braking performance evaluation model and the detection algorithm of the uneven wear of the brake shoe are integrated in the software.The infrared thermal image of the brake shoe temperature in the actual elevator is collected and stored in the database server.The image data in the database server is invoked in the software through the C/S architecture.The proposed method is verified by the experimental data analysis results.