| Relay is an automatic switching device with the isolation, and it is widely used in remote control,telemetry,communications, automatic control, mechatronicsand power electronicdevices.It is one of the most important control elementits , and its long-term reliability will directly affect the reliability of the system. Relay's electrical performance and its reliability are closely related, so the study on how to test the electrical properties of the relay (including theelectric arc characteristics and life) is necessary. This paper summarizes the electrical properties of domestic and international aspects of the relay test standards and test methods.Also this thesis explores the current research status on the arc characteristics under different air pressure.In this thesis,a test system of the relay's electrical properties is designed and built with the technique of virtual instrument. The system uses a high-performance data acquisition card with the sampling frequency up to 1M/s, and uses the technology of LabVIEW virtual instrument to automatic control the capture and storage of the voltage and current waveform and the alarm of failure such as weld during the test.On the same time ,the system also uses the technology of virtual instrument programming of the to reproduce the stored waveform and analyze the waveform signal,such as arc duration. On the basis of this system, the electrical life test of aerospace relay under inrush load (capacitive load) and the electrical life test of commercial automotive relay under resistive load were carried out. The former is mainly a surge of electrical life of the aerospace Relay; the latter is mainly for the study of weld during the test.Meanwhile,this article also designed and built a simulation system of vacuum environment.The main purpose of the system is to create a vacuum environment with the working vacuum between 1×105Pa1×10-3Pa and the maximum vacuum up to 1×10-4Pa.Also,the system have the function of the fix of the sample,the observation of the test, the connection and transmission of the signal . In this article,the design,the usage and the troubleshooting of the whole system are also described.With the simulation system of vacuum environment and the test system of the relay's electrical properties,the experiment on the arc characteristics under different air pressure is carried out. |
