Development Of Comprehensive Device For Preventive Test Of Insulation Safety Tools

Safety equipment is an important guarantee for the life safety of workers in high-voltage live working and preventive testing.Due to the existence of high-voltage safety problems and objective uncertainties(such as weak awareness of the test personnel,lack of experience,etc.),accidents in preventive testing of safety tools still occur.At present,the market’s preventive test equipment generally has defects,such as high-risk factor,low degree of automation,and single test item.Therefore,it is of great significance to develop a comprehensive device of preventive tests with low-risk factor and high degree of automation.This subject designs and develops a comprehensive device for preventive testing of safety tools.The integrated device is composed of three parts: the upper computer operating platform,the high-voltage test device and the detection device.The integrated device uses wireless communication technology for data interaction to ensure the safety of the test personnel;the high-voltage test device is divided into two parts: the high-voltage control device and the booster system.The former drives the output of the latter to ensure the accuracy of the test high-voltage;The physical isolation between the high-voltage test device and the detection device ensures the reliability of the integrated device.After the upper computer operating platform issues the project instruction,the high-voltage test device performs high-voltage tests on the safety tools,and the detection device measures the high-voltage sampling voltage and leakage current and uploads them to the upper computer operating platform for display and storage.Both the high-voltage control device and the detection device use the STM32F407ZGT6 processor as the control core.The former uses an external reference and a 20-bit high-precision D / A chip MAX5719 to output the reference voltage;the latter sends the current and voltage signals to a 16-bit high-precision A /D chip ADS8556 by sampling circuit with frequency measurement circuit to achieve synchronous sampling,and uploads calculate effective values of voltage and current to the upper computer.At the same time,in order to ensure the output waveform of the high-voltage test device,the FFT algorithm is used to analyze the harmonics of the output high voltage and calculate the total harmonic distortion.The high-voltage control device and the detection device have network communication function.The hardware uses the MAC layer of the processor and the external PHY chip DP83848 to realize the Ethernet interface,and adopt the WIFI module to realize wireless communication;the software uses the lightweight Lw IP protocol stack to achieve UDP Protocol communication transmission to ensure the timeliness of the test.The upper computer uses the current mainstream embedded development platform-Qt-as the integrated development environment.The GUI designed by Qt Designer has high efficiency and beautiful layout,which uses signal and slot mechanism and rich API to implement parameter entry,command issuance,display preservation and historical review.Based on the research background and significance of the comprehensive device for preventive testing of safety equipment,the subject combines the development status and market demand at home and abroad,and explained the relevant principles and algorithms,the design of software and hardware of the comprehensive device for preventive testing and the realization of each module of the upper computer platform.in detail.It is tested by using FLUKE8845 A high-precision digital multimeter and BD-3D multi-function calibrator.The test results show that the performance of the device achieves the expected design requirements.Finally,the deficiencies and improvement measures of the device are summarized and analyzed.